This work was supported by the U.S. Department of Energy (DOE) under Contract DE-AC36-08-GO28308 at NREL and Contract DE-AC05-76RL01830 at PNNL. The authors gratefully acknowledge the support of the DOE&#39;s Bioenergy Technologies Office.

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V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+of+fast+pyrolysis+of+biomass+and+product+upgrading.">Review of fast pyrolysis of biomass and product upgrading.</a> Biomass Bioenergy. 29, 68-94 (2012).</li><li>Elliott, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Historical+developments+in+hydroprocessing+bio-oils.">Historical developments in hydroprocessing bio-oils.</a> Energy Fuels. 21 (3), 1792-1815 (2007).</li><li>Wang, H., Male, J., Wang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+hydrotreating+of+pyrolysis+bio-oil+and+its+oxygen-containing+model+compounds.">Recent advances in hydrotreating of pyrolysis bio-oil and its oxygen-containing model compounds.</a> ACS Catal. 3 (5), 1047-1070 (2013).</li><li>Zacher, A. H., Olarte, M. V., Santosa, D. M., Elliott, D. C., Jones, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+and+perspective+of+recent+bio-oil+hydrotreating+research.">A review and perspective of recent bio-oil hydrotreating research.</a> Green Chem. 16, 491-515 (2014).</li><li>Elliott, D. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catalytic+Hydroprocessing+of+Fast+pyrolysis+bio-oil+from+pine+sawdust.">Catalytic Hydroprocessing of Fast pyrolysis bio-oil from pine sawdust.</a> Energy Fuels. 26 (6), 3891-3896 (2012).</li><li>Venderbosch, R. H., Ardiyanti, A. R., Wildschut, J., Oasmaa, A., Heeresb, H. J. 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B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Removal+of+residual+char+fines+from+pyrolysis+vapors+by+hot+gas+filtration.">Removal of residual char fines from pyrolysis vapors by hot gas filtration.</a> Developments in Thermochemical Biomass. , (1996).</li><li>Hoekstra, E., Hogendoorn, K. J. A., Wang, X., Westerhof, R. J. M., Kersten, S. R. A., van Swaaij, W. P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+pyrolysis+of+biomass+in+a+fluidized+bed+reactor:+In+situ+filtering+of+the+vapors.">Fast pyrolysis of biomass in a fluidized bed reactor: In situ filtering of the vapors.</a> Ind. Eng. Chem. Res. 48 (10), 4744-4756 (2009).</li><li>Elliott, D. C., Wang, H., French, R., Deutch, S., Iisa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrocarbon+liquid+production+from+biomass+via+hot-vapor-filtered+fast+pyrolysis+and+catalytic+hydroprocessing+of+the+bio-oil.">Hydrocarbon liquid production from biomass via hot-vapor-filtered fast pyrolysis and catalytic hydroprocessing of the bio-oil.</a> Energy Fuels. 28 (9), 5909-5917 (2014).</li><li>Howe, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Field-to-Fuel+Performance+Testing+of+Lignocellulosic+Feedstocks:+An+Integrated+Study+of+the+Fast+Pyrolysis/Hydrotreating+Pathway.">Field-to-Fuel Performance Testing of Lignocellulosic Feedstocks: An Integrated Study of the Fast Pyrolysis/Hydrotreating Pathway.</a> Energy Fuels. 29 (5), 3188-3197 (2015).</li><li>Wang, H., Wang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+Deactivated+Bio-oil+Hydrotreating+Catalysts.">Characterization of Deactivated Bio-oil Hydrotreating Catalysts.</a> Topics in Catalysis. 59, 65-72 (2015).</li></ol>

The authors declare that they have no competing financial interests.

In this paper, we described a detailed procedure for converting lignocellulosic biomass to fuel-range hydrocarbons via fast pyrolysis and catalytic hydrotreating. The NREL pyrolysis reactor system with a 5-cm inner diameter fluidized-bed reactor and the PNNL hydrotreater system with a 1.3-cm inner diameter fixed-bed catalytic reactor and their operation procedures are described in detail. These reactor systems could be used to conduct pyrolysis and hydrotreating tests in an efficient and safe manner. We used representative herbaceous feedstocks to produce liquid bio-oils in the pyrolysis reactor system, and then, the bio-oils were processed in the hydrotreating system with a two-stage catalyst bed including sulfided Ru/C and CoMo/Al2O3 as catalysts to produce fuel-range liquid hydrocarbons. The process also is applicable to pyrolysis of a wide range of biomass feedstocks including wood, grass, and corn stover and then upgrading the produced bio-oil to produce biofuels.16 The hydrotreater and hydrotreating process also could be used for upgrading other biomass-generated intermediates such as liquefaction oil (bio-crude) from biomass such as wood and algae.
Maximizing bio-oil yield during pyrolysis requires heating the biomass rapidly to sufficient temperature to achieve maximum volatilization of the biomass. For most biomass, this means temperatures of 500 to 600 &#176;C. A fluidized bed provides rapid heat transfer from the sand to the biomass, providing a high heating rate. The use of small particles also provides a higher heating rate. Typically a few percent higher bio-oil yield is achieved with biomass ground to &#60;0.5 mm than with biomass ground to &#60;2 mm. Maximizing yield also means minimizing thermal cracking of the vapors by keeping the residence time at temperature low (1 to 2 seconds). Pyrolysis vapors contain compounds with a wide range of boiling points. Thus, the hot piping tends to become fouled with liquid, repolymerized vapors and char. To avoid this condition, keep the auger temperature below 100 &#176;C and all surfaces between the reactor and condensation train above 400 &#176;C to avoid fouling, but below 500 &#176;C to minimize thermal cracking. Thorough coverage with heat tape is necessary to prevent cold spots and provide a uniform temperature. Sewn insulation pads with closures on them generally provide more uniform coverage, thereby resulting in more uniform temperature. It is important that the temperature drops rapidly in the first condenser to minimize the opportunity for repolymerization of high-boiling-point materials, which could lead to blockage of the condenser inlet. It also is necessary to use dry ice in the second condenser to maximize liquid recovery and prevent damage to gas-measurement and analysis instruments.
Some enhanced features were not mentioned in the basic fast pyrolysis procedure. It is useful to have a pressure gauge or transmitter near the reactor inlet. In addition, it is useful to measure differential pressure across the reactor and cyclone and to measure the final pressure and temperature at the dry test meter (to enable accurate volume calculations). It also is helpful to have additional thermocouples in the pyrolysis bed to verify that the bed is fluidizing uniformly enough to provide uniform temperatures. Typically, &#60;5 &#176;C spread is seen vertically through the bed. It also is useful to have nested-loop temperature control on the reactor. When a larger amount of oil is needed, it is helpful to install a valve on the bottom of the char receiver and mount a secondary char receiver below that, which in turn has a valve at the bottom with a jar loosely mounted to it. This makes it possible to empty the char receiver into the secondary receiver and finally down into the jar so that continuous operation can be maintained for many hours. Vibration is helpful to the operation. Manual pounding of the pipes can be used, but an automatic vibrator provides more reliable agitation. These can be operated continuously on the lock hopper and auger port to maintain a smooth feed flow through the feeder. Also, using an automatic vibrator on the secondary char receiver during char draining makes that operation much more reliable. Hot-vapor filtration enhances cracking and reduces bio-oil yield as shown above. Keeping the temperature of the filter low but still above condensation temperature (&#62;400&#176;C) minimizes cracking. An inert surface on the filter also may reduce cracking. The filter area needs to be large to reduce pressure drop.
The major limitation of the fast pyrolysis process is that the produced bio-oil has some major problematic properties such as high viscosity, corrosiveness, poor volatility, low heating value, and chemical instability, which limits their direct utilization and causes some issues during their upgrading. 6,7,8,9 A variant of fast pyrolysis, catalytic fast pyrolysis, wherein fast pyrolysis is integrated with a catalysis process to upgrade the pyrolysis vapor, and hydropyrolysis, wherein fast pyrolysis conducted in the presence of reactive gases such as H2, can lead to a higher quality bio-oil but suffer higher operational complexity and low product yield.4,8
Two-stage catalytic hydrotreating showed good processing results for converting bio-oil to fuel-range hydrocarbons. Bio-oils are known to be chemically unstable because of the presence of active species such as carbonyl and phenolic compounds that could undergo repolymerization and condensation at a low temperature, leading to a high propensity for forming carbonaceous materials and consequent catalyst deactivation and even plugging of catalyst bed. Therefore, the first stage hydrogenation step was critical for the process, and was used to stabilize bio-oil by hydrogenation of carbonyls and phenolics at a relative low temperature by using a proper hydrogenation catalyst. The performance of the hydrogenation catalyst was the key of the long-term stability and operability of the process. Oxygen removal by hydrodeoxygenation occurred at the second stage by a sulfide-based hydrotreating catalyst. The yield and properties of produced final oil product depended on the catalysts and conditions used in the second stage. Maximizing the yield of liquid final fuels could be achieved by using catalysts capable of generating C-C bonds, such as alkylation function, and optimized reaction parameters including reaction temperature, pressure, and space velocity. The major limitation of the hydrotreating process is that, because of some problematic properties in bio-oil such as chemical instability and the presence of contaminants17, the lifetime of hydrotreating catalysts, especially the first step hydrogenation catalysts, are still limited, which makes the overall process costly. Maximizing the lifetime of the catalysts used could be achieved by using more robust catalysts; optimized reaction parameters including reaction temperature, pressure, and space velocity; or pretreatment to lower the content of the active species or contaminants in bio-oil feeds.
The hydrotreater was operated at high pressures and reactor temperatures with flammable gases and liquids involved. Therefore, safety rules and procedure should be strictly followed.

Our society depends heavily on fossil fuels (e.g., oil, natural gas, coal, etc.). These resources are not sustainable energy sources and are being depleted at a rapidly increasing rate, leading to concerns regarding dwindling fossil-fuel resources, environmental consequences of CO2 emission, and economic problems.1,2,3,4 There is increasing demand for alternative and sustainable energy sources. Biomass is the only renewable and carbon-neutral resource for production of liquid fuels (biofuels) and carbon-based chemicals to replace fossil fuels in the current energy production and conversion system.3,4
Lignocellulosic biomass (e.g., woods, grass, energy crop, agricultural waste, etc.), which is currently the most abundant and least expensive biomass source, has attracted the most attention as a way to produce biofuels via various thermochemical and biological routes.3,4 Three primary routes have been the focus of the recent research: 1) biochemical or chemical conversion to sugars followed by aqueous-phase catalytic and biochemical processing to biofuels; 2) gasification to synthesis gas followed by catalytic conversion to biofuels or alcohols; and 3) pyrolysis or liquefaction to liquid bio-oils followed by catalytic upgrading to biofuels.3,4
The first route can only utilize the cellulose and hemicellulose portion of lignocellulosic biomass. Pyrolysis integrated with upgrading is considered to be a near-term viable technology for the direct production of biofuels.
Pyrolysis is the thermal decomposition of lignocellulosic biomass at temperatures between 400 and 550 &#176;C in the absence of oxygen.4,5,6 A number of reactions, such as depolymerization, dehydration, and C&#8722;C bond cleavage, occur during pyrolysis and lead to the formation of a complex mixture of more than 200 oxygenated compounds.4,5,6 Bio-oils in high yields (up to 75 wt% of dry feed) could be produced with up to 70% of the energy stored in the biomass feedstocks retained.4,5 However, direct use of the produced pyrolysis bio-oil as transportation fuels in standard equipment is problematic because of the high oxygen and water content, which lead to different physical and chemical properties such as high viscosity, corrosiveness, poor volatility, low heating value, and poor stability.6,7,8,9 Therefore, extensive oxygen removal is required to upgrade bio-oils to fuel-range hydrocarbons. Catalytic hydrotreating using solid catalysts in hydrogen is the most common route to upgrade bio-oil by oxygen removal through hydrodeoxygenation and hydrogenation reactions.6,7,8,9
Currently, one of the primary challenges for pyrolysis followed by hydrotreating is to achieve long-term steady operation, especially for the hydrotreating process in which the thermal instability of the bio-oil and inorganic and sulfur residues in bio-oil cause significant catalyst deactivation.10,11 The thermal instability of bio-oil has been addressed by low-temperature hydrogenation to stabilize the active species in bio-oil.11,12 Cleanup of bio-oil by removing inorganic residues, which could catalyze repolymerization of bio-oil fractions and deactivate hydrotreating catalysts by deposition, may be valuable. Hot-vapor filtration is one of the techniques to effectively reduce the inorganic content in bio-oil by removing char particulates during pyrolysis.13,14,15 Hot-vapor filtration is used downstream of the pyrolysis reactor to separate char fines from the pyrolysis gas/vapor stream at high temperature before condensation of the vapors.13,14,15
We report here the protocol used at the National Renewable Energy Laboratory (NREL) for biomass fast pyrolysis both with and without hot-vapor filtration to produce bio-oils using a fluidized-bed reactor and at Pacific Northwest National Laboratory (PNNL) for bio-oil hydrotreating to produce biofuels in a continuous-flow packed-bed catalytic reactor. The configurations of the reactor systems, the operating procedures, and the processing and analysis of feedstocks, bio-oils, and biofuels are described in detail. Results of pyrolysis processing of a representative biomass feedstock with or without hot-vapor-filtering and hydrotreating of the produced bio-oil are also presented along with an assessment of the impact of hot-vapor filtration.

<table><tbody><tr><td>&lt;strong&gt;Pyrolysis system&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Feedstock</td><td></td><td></td><td>Mill to pass 2 mm screen</td></tr><tr><td>Sand for bed material</td><td>Black Rock</td><td></td><td>Screen to 300-500 microns</td></tr><tr><td>Furnace</td><td>Thermcraft</td><td>TSP-3.75-0-24-3C-J13667/1A</td><td>Split tube furnace 3.75 ID X 24 L</td></tr><tr><td>Pyrolysis reactor</td><td>Custom-built at NREL</td><td></td><td>2&quot; diameter, height 17&quot;, dual staggered plate distributor, 316SS, Auger port is 2.5 cm above distributor and is cooled with air or water, there is a coiled 1/4&quot; 304 SS tube below the distributor to pre-heat the gas</td></tr><tr><td>Cyclone</td><td>Custom-built at NREL</td><td></td><td>1&quot; diameter</td></tr><tr><td>Cyclone receiver</td><td>Custom-built at NREL</td><td></td><td>1 L capacity</td></tr><tr><td>Cyclone secondary receiver</td><td>Custom-built at NREL</td><td></td><td>1 L capacity</td></tr><tr><td>Hot vapor filter</td><td>Serv-A-Pure</td><td>SC2-0P10B34-X</td><td>316SS, 10 inches long, 2.0 micron</td></tr><tr><td>2-neck round-bottomed flasks</td><td></td><td></td><td>500 ml</td></tr><tr><td>Electrostatic precipitator</td><td>Allen Scientific Glassware, NREL-built electrodes</td><td>Custom built</td><td>2&quot; diameter 10&quot; long ground electrode, glass enclosed, stop-cock on bottom</td></tr><tr><td>High-voltage power supply</td><td>Spellman High Voltage</td><td>Bertan 803C-300P</td><td>30 kV max, 0.5 mA</td></tr><tr><td>Cold-finger condenser</td><td>Aldrich</td><td>Z164038</td><td></td></tr><tr><td>Coalescing filter</td><td>Finite</td><td>10C15-060</td><td></td></tr><tr><td>Dry test meter</td><td>American Meter</td><td>DTM-200A</td><td>with IMAC counter</td></tr><tr><td>Gas chromatograph</td><td>Varian</td><td>CP-4900</td><td>MS5A, PBQ, CP-Sil columns</td></tr><tr><td>Hydrogen detector</td><td>Gerhard Wagner</td><td>TCM-4</td><td>thermal conductivity detector</td></tr><tr><td>Non-Dispersive Infrared Spectrometer</td><td>California Analytical</td><td>Model 300</td><td>Carbon monoxide 0-5%, 0-25%, carbon dioxide 0-5%, 0-20%, methane 0-5,000 ppmv, 0-3%</td></tr><tr><td>Mass flow controller</td><td>Celerity (now Tylan)</td><td>Unit 7301</td><td>0-20 SLM reactor bottom, 0-10 SLM auger, 0-2 slm purges, 0-5 slm air</td></tr><tr><td>Auger</td><td>Auger Manufacturing Specialists</td><td>110520</td><td>3/8&quot; Dia SS RH Auger 18&quot;</td></tr><tr><td>Motor for Auger</td><td>Leeson</td><td></td><td>Gearmotor-Parallel Shaft, 94 rpm, 1/15 HP, TEFC, 115 VAC</td></tr><tr><td>Feeding system: Motor for hopper</td><td>Lenze</td><td>VDE0530</td><td>7KB4-7-100H Motor Ac Helical Gearbox 3PH 0.25 kW 1.4/0.82 A</td></tr><tr><td>Feeding system: Hopper and Loss in weight feeder</td><td>K-TRON Soder</td><td>KCL24T20</td><td>with K10S controller</td></tr><tr><td>Feeding system: Valves</td><td>Swagelok</td><td>SS-65TS16</td><td>151 bar at 37 &amp;deg;C and 6.8 bar at 232 &amp;deg;C</td></tr><tr><td>Control system</td><td>Opto22</td><td>SNAP-PAC parts</td><td></td></tr><tr><td>Heat cables</td><td>McMaster-Carr</td><td>4550T152 and similar</td><td>Extreme-Temperature (1,400 &amp;deg;F), heavy insulation for use on metal</td></tr><tr><td>Ball Vibrator</td><td>Vibtec</td><td>K 8</td><td></td></tr><tr><td>U-tube</td><td>Custom-built at NREL</td><td></td><td>1/4&quot; PFA and stainless steel tubing, 1.4 m tall</td></tr><tr><td>&lt;strong&gt;Hydrotreating system&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Ru on carbon catalyst</td><td>Fabricated at PNNL</td><td></td><td>7.6 wt% Ru on carbon</td></tr><tr><td>3% Co and 9% Mo on Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; catalyst</td><td>Alfa-Aesar</td><td>45579</td><td>Cobalt oxide, typically 3.4-4.5%, Molybdenum oxide typically 11.5-14.5% on alumina</td></tr><tr><td>Feeding pumps</td><td>ISCO</td><td>500D</td><td>Syringe pump, 500 ml cylinder capacity</td></tr><tr><td>Mass flow controller</td><td>Brooks</td><td>SLA5850S1BAF4B1A1</td><td></td></tr><tr><td>Temperatrue controller</td><td>Cole-Parmer</td><td>WU-89000-10</td><td>Digi-Sense Advanced Temperature Controller, 115 V</td></tr><tr><td>Thermocouples</td><td>Omega</td><td></td><td>K-type thermocouples</td></tr><tr><td>Pressure transducer</td><td>Omega</td><td>PX309-3KG5V</td><td></td></tr><tr><td>Heat tapes</td><td>Cole-Parmer</td><td>EW-03106-27</td><td>Dual element heating tape, 1/2 in x 12 ft, 936 watts, 120 VAC w/ 2-prong plug</td></tr><tr><td>Digital pressure gauge</td><td>Omega</td><td>DPG4000-3K</td><td>High Accuracy Digital Pressure Gauge, with Data Logging Capability</td></tr><tr><td>Back pressure regulator</td><td>Mity-Mite</td><td></td><td></td></tr><tr><td>Gas flow meter</td><td>Mesa Labs</td><td>200-220L</td><td>Dry Cal, Definer 220 Low Flow&amp;nbsp;</td></tr><tr><td>Hydrotreating reactor, cross, tee, fittings</td><td>Parker, Autoclave</td><td></td><td></td></tr><tr><td>Combustible gas sensor</td><td>SMC</td><td>5100-02-IT-S1-01-00-0-0</td><td>Combustible gas detection sensor, 24 VDC power, analog 4-20 MADC output with modbus, no relays</td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;S sensor</td><td>SMC</td><td>5100-05-IT-S1-01-00-0-0</td><td>H&lt;sub&gt;2&lt;/sub&gt;S toxic gas sensor module, 24 VDC power, analog 4-20 MADC output with modbus, no relays</td></tr><tr><td>Ventilation sensor</td><td>TSI</td><td>FHM10</td><td>Fume Hood Monitor FHM10</td></tr><tr><td>Micro-Gas chromatograph</td><td>Inficon</td><td>Inficon 3000</td><td>Four-channel micro-GC with molecular sieve, Plot U, Alumina, and Stabilwax columns</td></tr><tr><td>Lab-view based monitering and controlling system</td><td>Custom-built at PNNL</td><td></td><td>Using National Instruments parts and Labview software</td></tr></tbody></table>

biomass conversion to produce hydrocarbon liquid fuel via hot-vapor filtered fast pyrolysis and catalytic hydrotreating

Lignocellulosic biomass conversion to produce biofuels has received significant attention because of the quest for a replacement for fossil fuels. Among the various thermochemical and biochemical routes, fast pyrolysis followed by catalytic hydrotreating is considered to be a promising near-term opportunity. This paper reports on experimental methods used 1) at the National Renewable Energy Laboratory (NREL) for fast pyrolysis of lignocellulosic biomass to produce bio-oils in a fluidized-bed reactor and 2) at Pacific Northwest National Laboratory (PNNL) for catalytic hydrotreating of bio-oils in a two-stage, fixed-bed, continuous-flow catalytic reactor. The configurations of the reactor systems, the operating procedures, and the processing and analysis of feedstocks, bio-oils, and biofuels are described in detail in this paper. We also demonstrate hot-vapor filtration during fast pyrolysis to remove fine char particles and inorganic contaminants from bio-oil. Representative results showed successful conversion of biomass feedstocks to fuel-range hydrocarbon biofuels and, specifically, the effect of hot-vapor filtration on bio-oil production and upgrading. The protocols provided in this report could help to generate rigorous and reliable data for biomass pyrolysis and bio-oil hydrotreating research.

The fast pyrolysis of a representative herbaceous biomass, switchgrass, with or without hot-vapor filtration and the catalytic hydrotreating of the product bio-oil are used as an example for the process reported here. More details of these experiments can be found in detail in our recent publication.15
Hot-vapor-filtered fast pyrolysis 
Table 1 shows bio-oil, char, and gas yields produced with and without the hot-vapor filter for a typical herbaceous feedstock. For the control experiment without hot-vapor filtration, the vapors passed though the filter housing but the filter was not installed. This kept the residence time in the two experiments the same so any difference is due to the filter only. The bio-oil yields were 52% to 56%, indicating successful conversion of the major portion of the biomass to liquid intermediate oils. A photo of a representative bio-oil sample is shown in Figure 4. The mass balance closures were 86% to 90%. Light vapors that were not properly collected in the condensation train were one source of mass loss. Pyrolysis oils contain several low-boiling-point compounds, such as hydroxyacetaldehyde (boiling point 20.2 &#176;C), that are difficult to condense. Adding a second dry-ice trap will improve the recovery of the light condensable compounds. Performing experiments with higher biomass feed rates than reported here will improve recovery of the light vapors by increasing the vapor concentration prior to condensation. The escape of light condensable compounds can be verified by gas chromatography-mass spectroscopy analysis of the exit gas. The mass balances were relatively low for the herbaceous feedstock, likely because of escaping light char, which was produced from the switchgrass in relatively large quantities. Cracking reactions occur at the filter so inclusion of the hot-vapor filter reduced the oil yields and increased the gas yields.
Table 2 and Figures 5 and 6 show the analysis results of herbaceous feedstock and the bio-oils produced. Hot-vapor filtering reduced the ash residue in the bio-oil from 1.45% to below the detection limit. Various inorganics, such as aluminum, calcium, iron, potassium, magnesium, sodium, phosphorous, and silicon, were observed in the bio-oils, and they mainly originate from the biomass feedstock. Hot-vapor filtering significantly decreased the inorganic contents in the bio-oil, indicating that hot-vapor filtering was a powerful protocol for effectively reducing the trace element content in the bio-oils by removing char and ash particulates. Hot-vapor filtering also decreased the carbon content and increased the oxygen content in the bio-oils. Woody feedstocks have low ash contents compared to herbaceous feedstocks, and lower reductions in the bio-oil ash and inorganic contents are observed.15
Catalytic hydrotreating of bio-oil 
The analytical results of the produced bio-oil were consistent with the fact that bio-oils produced from such process are not of sufficient quality for direct use in internal combustion engines. Therefore, upgrading of bio-oil is required. The two bio-oil samples were upgraded by catalytic hydrotreating in the hydrotreater system under the conditions discussed above.
Bio-oils are known to plug the hydrotreating reactors as chars or polymerization products of active species in bio-oils accumulate in the catalyst bed. Therefore, the pressure drop across the catalyst beds during the hydrotreating tests is an important indicator of accumulating chars or polymerization products. The hot-vapor filtered bio-oil performed nearly flawlessly for 60 hours TOS in the hydrotreating test. However, the non-filtered bio-oil had &#8764;5 wt% undissolved solids, which separated out in the pump and were not treated. Even with these untreated solids, there was still a pressure drop buildup after 50 hours TOS, probably because of the residual solids in the non-filtered bio-oil plugging the packed catalyst bed.
Tables 3 and 4 and Figures 5 and 7 list the yield of the products for bio-oil hydrotreating at different TOSs. Phase-separated liquid products, including an upgraded oil phase and an aqueous phase, and gaseous products, including CH4, C2H6, C3H8, C4H10, CO, and CO2, were produced. Figure 4 shows a photo of a reparative upgraded oil sample. Table 5 shows the analysis results of upgraded oil and Figure 5 compares the elemental analysis results of the bio-oil and the upgraded oil. Hydrotreating was very effective at reducing oxygen, sulfur, and nitrogen and adding hydrogen significantly from the bio-oil feed. The oxygen content in the upgraded oil was &#8764;2.0 wt%, which was significantly lower than 35 to 40 wt% of oxygen in the bio-oil feed. The hydrogen-to-carbon ratio of the upgraded oil was &#8764;1.7, compared to &#8764;1.3 for the bio-oil feed. The trend of density of the upgraded oil, which increased from 0.81 to 0.83 g/ml over the period of the test, suggests a mild catalyst deactivation over the 60 hour TOS.
As shown in Figure 7, comparisons of hydrotreated products between the hot-vapor filtered and non-filtered bio-oil showed that hot-vapor filtered bio-oil led to a slightly higher water-to-upgraded oil ratio, which is consistent with the higher oxygen content in the hot-vapor-filtered bio-oil feed. The properties of upgraded oil for the two bio-oils were very similar. The major difference between the hydrotreating of hot-vapor-filtered and non-filtered bio-oil was that the used catalyst beds of hot-vapor-filtered bio-oil showed much less deposition of inorganics compared to the catalyst beds used with non-filtered bio-oils.
<img alt="Figure 1" src="/files/ftp_upload/54088/54088fig1.jpg" /> 
Figure 1. Schematic for the 5-cm fluidized-bed pyrolysis reactor system. There is a hot-vapor filter, a condensation system, and a gas-measurement system. <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" src="/files/ftp_upload/54088/54088fig2.jpg" /> 
Figure 2. Schematic of the mini-reactor hydrotreater system. (MFC: mass flow controller; RD: rupture disc; PT: pressure transducer; PI: pressure indicator (gauge); BPR: back-pressure regulator; PR: pressure regulator) <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" src="/files/ftp_upload/54088/54088fig3.jpg" /> 
Figure 3. Schematic of the catalyst bed in the mini-hydrotreater reactor. The temperature profile of the catalyst bed is shown in the left and the position of catalysts of each stage is shown in the right. <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" src="/files/ftp_upload/54088/54088fig4.jpg" /> 
Figure 4. Photos of a representative bio-oil samples (left) and a representative upgraded oil sample (right). <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig4large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" src="/files/ftp_upload/54088/54088fig5.jpg" /> 
Figure 5. Comparison of elemental analysis results of the herbaceous feedstock (switchgrass), the bio-oil produced with hot-vapor filtration, and the upgraded oil. Carbon, hydrogen, and oxygen content did not change much after fast pyrolysis of biomass, however, oxygen content decreased significantly and hydrogen content increased after bio-oil hydrotreating. <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig5large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 6" src="/files/ftp_upload/54088/54088fig6.jpg" /> 
Figure 6. Comparison of oil yield, carbon efficiency, and some properties of bio-oil from hot-vapor filtered and non-filtered pyrolysis. This demonstrates the impact of hot gas filtration of pyrolysis vapors prior to condensation. Hot gas filtration eliminates inorganic residues but it also affects pyrolysis oil yield [3-LM] and oil properties such as oil oxygen content. <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig6large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 7" src="/files/ftp_upload/54088/54088fig7.jpg" /> 
Figure 7. Comparison of hydrotreating results of bio-oils from hot-vapor filtered and non-filtered pyrolysis. Hot-vapor filtered bio-oil leads to a slightly higher water-to-fuel ratio and the properties of upgraded fuel for the two bio-oils are very similar. The major difference between hydrotreating of the two pyrolysis oils is that the catalyst bed of hot-vapor-filtered bio-oil showed much less deposition of minerals. <a href="http://cloudflare.jove.com/files/ftp_upload/54088/54088fig7large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Table 1" src="/files/ftp_upload/54088/54088table1.jpg" /> 
Table 1. Yields of major pyrolysis products (bio-oil, char, and gas) and mass balance closures for pyrolysis of an herbaceous feedstock (switchgrass) with and without hot-vapor filtration.

<img alt="Table 2" src="/files/ftp_upload/54088/54088table2.jpg" /> 
Table 2. Analysis of the representative herbaceous feedstock (switchgrass) and bio-oil produced with and without hot-vapor filtration.

<img alt="Table 3" src="/files/ftp_upload/54088/54088table3.jpg" /> 
Table 3. Yield of major hydrotreating products at the different TOSs for hot-vapor filtered and non-filtered representative bio-oil.

<img alt="Table 4" src="/files/ftp_upload/54088/54088table4.jpg" /> 
Table 4. Produced gas composition during the hydrotreating of representative bio-oils.

<img alt="Table 5" src="/files/ftp_upload/54088/54088table5.jpg" /> 
Table 5. Analysis of the upgraded oil products from the hydrotreating of representative bio-oils.

Watch this Scientific Journal Video about Biomass Conversion to Produce Hydrocarbon Liquid Fuel Via Hot-vapor Filtered Fast Pyrolysis and Catalytic Hydrotreating at JoVE.com

Biomass Conversion to Produce Hydrocarbon Liquid Fuel Via Hot-vapor Filtered Fast Pyrolysis and Catalytic Hydrotreating

Experimental methods for fast pyrolysis of lignocellulosic biomass to produce bio-oils and for the catalytic hydrotreating of bio-oils to produce fuel range hydrocarbons are presented. Hot-vapor filtration during fast pyrolysis to remove fine char particles and inorganic contaminants from bio-oil was also assessed.

Lignocellulosic biomass conversion to produce biofuels has received significant attention because of the quest for a replacement for fossil fuels. Among ...

biomass-conversion-to-produce-hydrocarbon-liquid-fuel-via-hot-vapor

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SCIENTISTS IN ACTION

26.4K Views.  Pacific Northwest National Laboratory (PNNL).  Experimentele werkwijzen voor snelle pyrolyse van lignocellulosebiomassa bio-olie te produceren en voor de katalytische hydrobehandeling van bio-oliën actieradius koolwaterstoffen worden gepresenteerd. Hot-damp filtratie tijdens snelle pyrolyse tot fijne deeltjes char en anorganische verontreinigingen uit bio-olie te verwijderen werd ook beoordeeld. 

Video: Biomass Conversion to Produce Hydrocarbon Liquid Fuel Via Hot-vapor Filtered Fast Pyrolysis and Catalytic Hydrotreating

Evaluation of Integrated Anaerobic Digestion and Hydrothermal Carbonization for Bioenergy Production

Lignocellulosic biomass is one of the most abundant yet underutilized renewable energy resources. Both anaerobic digestion (AD) and hydrothermal carbonization (HTC) are promising technologies for bioenergy production from biomass in terms of biogas and HTC biochar, respectively. In this study, the combination of AD and HTC is proposed to increase overall bioenergy production. Wheat straw was anaerobically digested in a novel upflow anaerobic solid state reactor (UASS) in both mesophilic (37 &#176;C) and thermophilic (55 &#176;C) conditions. Wet digested from thermophilic AD was hydrothermally carbonized at 230 &#176;C for 6 hr for HTC biochar production. At thermophilic temperature, the UASS system yields an average of 165 LCH4/kgVS&#160;(VS: volatile solids) and 121 L CH4/kgVS&#160;at mesophilic AD over the continuous operation of 200 days. Meanwhile, 43.4 g of HTC biochar with 29.6 MJ/kgdry_biochar was obtained from HTC of 1 kg digestate (dry basis) from mesophilic AD. The combination of AD and HTC, in this particular set of experiment yield 13.2 MJ of energy per 1 kg of dry wheat straw, which is at least 20% higher than HTC alone and 60.2% higher than AD only.

A novel Upflow Anaerobic Solid State (UASS) reactor was used for biogas production from fibrous feedstock. Digestate from UASS reactor was hydrothermally carbonized into HTC biochar in a pressurized batch reactor. The integration of the two bioenergy concepts was applied in this study to increase overall bioenergy production.

Lignocellulosic biomass is one of the most abundant yet underutilized renewable energy resources. Both anaerobic digestion (AD) and hydrothermal ...

Environment

Pretreatment of Lignocellulosic Biomass with Low-cost Ionic Liquids

A number of ionic liquids (ILs) with economically attractive production costs have recently received growing interest as media for the delignification of a variety of lignocellulosic feedstocks. Here we demonstrate the use of these low-cost protic ILs in the deconstruction of lignocellulosic biomass (Ionosolv pretreatment), yielding cellulose and a purified lignin. In the most generic process, the protic ionic liquid is synthesized by accurate combination of aqueous acid and amine base. The water content is adjusted subsequently. For the delignification, the biomass is placed into a vessel with IL solution at elevated temperatures to dissolve the lignin and hemicellulose, leaving a cellulose-rich pulp ready for saccharification (hydrolysis to fermentable sugars). The lignin is later precipitated from the IL by the addition of water and recovered as a solid. The removal of the added water regenerates the ionic liquid, which can be reused multiple times. This protocol is useful to investigate the significant potential of protic ILs for use in commercial biomass pretreatment/lignin fractionation for producing biofuels or renewable chemicals and materials.

The pretreatment of lignocellulosic biomass with protic low-cost ionic liquids is shown, resulting in a delignified cellulose-rich pulp and a purified lignin. The pulp gives rise to high glucose yields after enzymatic saccharification.

A number of ionic liquids (ILs) with economically attractive production costs have recently received growing interest as media for the delignification of ...

A Toolkit to Enable Hydrocarbon Conversion in Aqueous Environments

This work puts forward a toolkit that enables the conversion of alkanes by Escherichia coli and presents a proof of principle of its applicability. The toolkit consists of multiple standard interchangeable parts (BioBricks)9 addressing the conversion of alkanes, regulation of gene expression and survival in toxic hydrocarbon-rich environments.
A three-step pathway for alkane degradation was implemented in E. coli to enable the conversion of medium- and long-chain alkanes to their respective alkanols, alkanals and ultimately alkanoic-acids. The latter were metabolized via the native &beta;-oxidation pathway. To facilitate the oxidation of medium-chain alkanes (C5-C13) and cycloalkanes (C5-C8), four genes (alkB2, rubA3, rubA4and rubB) of the alkane hydroxylase system from Gordonia sp. TF68,21 were transformed into E. coli. For the conversion of long-chain alkanes (C15-C36), theladA gene from Geobacillus thermodenitrificans was implemented. For the required further steps of the degradation process, ADH and ALDH (originating from G. thermodenitrificans) were introduced10,11. The activity was measured by resting cell assays. For each oxidative step, enzyme activity was observed.
To optimize the process efficiency, the expression was only induced under low glucose conditions: a substrate-regulated promoter, pCaiF, was used. pCaiF is present in E. coli K12 and regulates the expression of the genes involved in the degradation of non-glucose carbon sources.
The last part of the toolkit - targeting survival - was implemented using solvent tolerance genes, PhPFD&alpha; and &beta;, both from Pyrococcus horikoshii OT3. Organic solvents can induce cell stress and decreased survivability by negatively affecting protein folding. As chaperones, PhPFD&alpha; and &beta; improve the protein folding process e.g. under the presence of alkanes. The expression of these genes led to an improved hydrocarbon tolerance shown by an increased growth rate (up to 50%) in the presences of 10% n-hexane in the culture medium were observed.
Summarizing, the results indicate that the toolkit enables E. coli to convert and tolerate hydrocarbons in aqueous environments. As such, it represents an initial step towards a sustainable solution for oil-remediation using a synthetic biology approach.

A sustainable auto regulating bacterial system for the remediation of oil pollutions was designed using standard interchangeable DNA parts (BioBricks). An engineered E. coli strain was used to degrade alkanes via &beta;-oxidation in toxic aqueous environments. The respective enzymes from different species showed alkane degradation activity. Additionally, an increased tolerance to n-hexane was achieved by introducing genes from alkane-tolerant bacteria.

This work puts forward a toolkit that enables the conversion of alkanes by Escherichia coli and presents a proof of principle of its applicability. The ...

Bioengineering

Laboratory Production of Biofuels and Biochemicals from a Rapeseed Oil through Catalytic Cracking Conversion

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil (HGO) for production of transportation fuels through a fluid catalytic cracking (FCC) route. Cracking experiments are performed with a fully automated reaction unit at a fixed weight hourly space velocity (WHSV) of 8 hr-1, 490-530 &#176;C, and catalyst/oil ratios of 4-12 g/g. When a feed is in contact with catalyst in the fluid-bed reactor, cracking takes place generating gaseous, liquid, and solid products. The vapor produced is condensed and collected in a liquid receiver at -15 &#176;C. The non-condensable effluent is first directed to a vessel and is sent, after homogenization, to an on-line gas chromatograph (GC) for refinery gas analysis. The coke deposited on the catalyst is determined in situ by burning the spent catalyst in air at high temperatures. Levels of CO2 are measured quantitatively via an infrared (IR) cell, and are converted to coke yield. Liquid samples in the receivers are analyzed by GC for simulated distillation to determine the amounts in different boiling ranges, i.e., IBP-221 &#176;C (gasoline), 221-343 &#176;C (light cycle oil), and 343 &#176;C+ (heavy cycle oil). Cracking of a feed containing canola oil generates water, which appears at the bottom of a liquid receiver and on its inner wall. Recovery of water on the wall is achieved through washing with methanol followed by Karl Fischer titration for water content. Basic results reported include conversion (the portion of the feed converted to gas and liquid product with a boiling point below 221 &#176;C, coke, and water, if present) and yields of dry gas (H2-C2's, CO, and CO2), liquefied petroleum gas (C3-C4), gasoline, light cycle oil, heavy cycle oil, coke, and water, if present.

This paper presents an experimental method to produce biofuels and biochemicals from canola oil mixed with a fossil-based feed in the presence of a catalyst at mild temperatures. Gaseous, liquid, and solid products from a reaction unit are quantified and characterized. Conversion and individual product yields are calculated and reported.

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil ...

Reducing Willow Wood Fuel Emission by Low Temperature Microwave Assisted Hydrothermal Carbonization

Biomass is a sustainable fuel, as its CO2 emissions are reintegrated in biomass growth. However, the inorganic precursors in the biomass cause a negative environmental impact and slag formation. The selected short rotation coppice (SRC) willow wood has a high ash content (<img alt="Equation 1" src="/files/ftp_upload/58970/58970eq1.jpg" /> = 1.96%) and, therefore, a high content of emission and slag precursors. Therefore, the reduction of minerals from SRC willow wood by low temperature microwave assisted hydrothermal carbonization (MAHC) at 150 &#176;C, 170 &#176;C, and 185 &#176;C is investigated. An advantage of MAHC over conventional reactors is an even temperature conductance in the reaction medium, as microwaves penetrate the whole reactor volume. This allows a better temperature control and a faster cooldown. Therefore, a succession of depolymerization, transformation and repolymerization reactions can be analyzed effectively. In this study, the analysis of the mass loss, ash content and composition, heating values and molar O/C and H/C ratios of the treated and untreated SCR willow wood showed that the mineral content of the MAHC coal was reduced and the heating value increased. The process water showed a decreasing pH and contained furfural and 5-methylfurfural. A process temperature of 170 &#176;C showed the best combination of energy input and ash component reduction. The MAHC allows a better understanding of the hydrothermal carbonization process, while a large-scale industrial application is unlikely because of the high investment costs.

A protocol for the emission precursor depletion from low quality biomass by low temperature microwave assisted hydrothermal carbonization treatment is presented. This protocol includes the microwave parameters and the analysis of the biocoal product and process water.

Biomass is a sustainable fuel, as its CO2 emissions are reintegrated in biomass growth. However, the inorganic precursors in the biomass cause a negative ...

Transformation of Organic Household Leftovers into a Peat Substitute

A two-step procedure is described for the synthesis of a carbon material with a similar composition and properties as peat. The produced hydrochar is made suitable for agricultural applications by removing plant growing inhibitory substances. Wet household waste such as fruit peel, coffee grounds, inedible vegetable parts, or wet lignocellulosic material in general, are treated in presence of water at 215 &#x00B0;C and 21 bar in an autoclave, i.e., by hydrothermal carbonization. All these leftovers have a considerable water content of up to 90 weight % (wt%). Adding water extends the procedure to drier materials such as nutshells or even garden prunings and compostable polymers, i.e., the plastic bag for collection of the leftovers.
Usually, the resulting carbon material, called hydrochar, produces a negative effect on plant growth when added to soil. It is supposed that this effect is caused by adsorbed phytotoxic compounds. A simple post-treatment under inert atmosphere (absence of oxygen) at 275 &#x00B0;C removes these substances. Therefore, the raw hydrochar is placed on a glass frit of a vertical tubular quartz reactor. A nitrogen gas flow is applied in down-flow direction. The tube is heated to the desired temperature by means of a heating mantle for up to one hour.
The success of the thermal treatment is easily quantified by thermogravimetry (TG), carried out in air. A weight loss is determined when the temperature of 275 &#x00B0;C is reached, since volatile content is desorbed. Its amount is reduced in the final material, in comparison to the untreated hydrochar.
The two-step treatment converts household leftovers, including compostable bags employed for their collection, into a carbon material that may serve as plant growth promoter and, at the same time, as a carbon sink for climate change mitigation.

A protocol for hydrothermal carbonization of vegetable food waste in an autoclave is presented, with subsequent dry thermal treatment at 275 &#x00B0;C in a continuous flow reactor desorbing volatile organic substances. The aim is to produce a carbon material suitable as soil amendment product or substrate component.

A two-step procedure is described for the synthesis of a carbon material with a similar composition and properties as peat. The produced hydrochar is made ...

Qualitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae Using 2D Gas Chromatography with Time-of-flight Mass Spectrometry

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in complex mixtures. It is often used to analyze gasoline, jet fuel, diesel, bio-diesel and the organic fraction of bio-crude/bio-oil. In most of those analyses, the first dimension of separation is non-polar, followed by a polar separation. The aqueous fractions of bio-crude and other aqueous samples from biofuels production have been examined with similar column combinations. However, sample preparation techniques such as derivatization, solvent extraction, and solid-phase extraction were necessary prior to analysis. In this study, aqueous fractions obtained from the hydrothermal liquefaction of algae were characterized by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry without prior sample preparation techniques using a polar separation in the first dimension followed by a non-polar separation in the second. Two-dimensional plots from this analysis were compared with those obtained from the more traditional column configuration. Results from qualitative characterization of the aqueous fractions of algal bio-crude are discussed in detail. The advantages of using a polar separation followed by a non-polar separation for characterization of organics in aqueous samples by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry are highlighted.

A two-dimensional gas chromatography-time-of-flight mass spectrometry method is described for characterization of the aqueous fraction of bio-crude produced from hydrothermal liquefaction of algae. This protocol can also be employed to analyze the aqueous fraction of liquid products from fast pyrolysis, catalytic fast pyrolysis, catalytic deoxygenation and hydro-treating.

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in ...

Fast Pyrolysis of Biomass Residues in a Twin-screw Mixing Reactor

Fast pyrolysis is being increasingly applied in commercial plants worldwide. They run exclusively on woody biomass, which has favorable properties for conversion with fast pyrolysis. In order to increase the synergies of food production and the energetic and/or material use of biomass, it is desirable to utilize residues from agricultural production, e.g., straw. The presented method is suitable for converting such a material on an industrial scale. The main features are presented and an example of mass balances from the conversion of several biomass residues is given. After conversion, fractionated condensation is applied in order to retrieve two condensates &#8212; an organic-rich and an aqueous-rich one. This design prevents the production of fast pyrolysis bio-oil that exhibits phase separation. A two phase bio-oil is to be expected because of the typically high ash content of straw biomass, which promotes the production of water of reaction during conversion.
Both fractionated condensation and the use of biomass with high ash content demand a careful approach for establishing balances. Not all kind of balances are both meaningful and comparable to other results from the literature. Different balancing methods are presented, and the information that can be derived from them is discussed.

A procedure for thermochemical conversion of biomass residues is presented that aims at maximizing the yield of liquid products (fast pyrolysis). It is based on a technology proven on an industrial scale and especially suitable for treating a straw type of biomass.

Fast pyrolysis is being increasingly applied in commercial plants worldwide. They run exclusively on woody biomass, which has favorable properties for ...

Biodiesel Synthesis by Ultrasonic-Assisted Transesterification of Vegetable Oils

Ultrasonic-Assisted Preparation of Biodiesel Products from Vegetable Oils

Utilizing vegetable oil as a sustainable feedstock, this study presents an innovative approach to ultrasonic-assisted transesterification for biodiesel synthesis. This alkaline-catalyzed procedure harnesses ultrasound as a potent energy input, facilitating the rapid conversion of extra virgin olive oil into biodiesel. In this demonstration, the reaction is run in an ultrasonic bath under ambient conditions for 15 min, requiring a 1:6 molar ratio of extra virgin olive oil to methanol and a minimum amount of KOH as the catalyst. The physiochemical properties of biodiesel are also reported. Emphasizing the remarkable advantages of ultrasonic-assisted transesterification, this method demonstrates notable reductions in reaction and separation times, achieving near-perfect purity (~100%), high yields, and negligible waste generation. Importantly, these benefits are achieved within a framework that prioritizes safety and environmental sustainability. These compelling findings underscore the effectiveness of this approach in converting vegetable oil into biodiesel, positioning it as a viable option for both research and practical applications.

Author Spotlight: Employing Green-Chemistry Principles for Safe and Sustainable Synthesis of Biodiesels

A safe ultrasonic-assisted transesterification method for vegetable oils using an alkaline catalyst is presented here. The method is rapid and efficient for preparing pure biodiesel products.

Utilizing vegetable oil as a sustainable feedstock, this study presents an innovative approach to ultrasonic-assisted transesterification for biodiesel ...

Hydrogenation

Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA
This experiment will demonstrate the hydrogenation of chalcone as an example of an alkene hydrogenation reaction (Figure 1). In this experiment, palladium on carbon (Pd/C) will be used as a heterogeneous catalyst for the process. A balloon will be used to supply the hydrogen atmosphere.
<img alt="Figure 1" src="/files/ftp_upload/10350/10350fig1.jpg" /> 
Figure 1: Diagram showing the hydrogenation of chalcone to 3-phenylpropiophenone.

Catalytic Hydrogenation of Alkene: Applications in Chemistry

Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA
This experiment will demonstrate the hydrogenation of ...

Biomass Conversion to Produce Hydrocarbon Liquid Fuel Via Hot-vapor Filtered Fast Pyrolysis and Catalytic Hydrotreating

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