Title: Catalytic Products from a Bench-Scale, Simulated Fluidized-Bed Pyrolyzer Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 23, 2010
Publication Date: September 23, 2010
Citation: Compton, D.L., Jackson, M.A., Boateng, A.A. 2010. Catalytic products from a bench-scale, simulated fluidized-bed pyrolyzer [abstract]. TCS 2010: Symposium on Thermal and Catalytic Sciences for Biofuels and Biobased Products. p. 51. Technical Abstract: Biomass (e.g. lignocellulosics and lipids) were catalytically converted under thermochemical conditions to bio-based, fungible industrial chemicals and products. The focus was on high temperature catalytic conversions of feedstocks in a bench-scale reactor designed to replicate a packed- or fluidized-bed pilot-scale pyrolysis reactor. The exploratory research examined the impact of various catalyst functionalities on thermochemical product formation. Reaction parameters such as temperature, reaction time, and catalyst:feedstock ratios were examined for effects on product formation. A 7.5-ml volume cell, constructed from 0.5 mm stainless steel walls was loaded with 20 to 800 mg of lipid or lignocellulosic feedstock intimately mixed with 700 mg to 4.50 g of catalyst. The feedstock was loaded at 20 wt% of the total feedstock/catalyst load. The feestock/catalyst load was capped with quartz wool. The cell was heated using four propane-fueled Bunsen burners controlled by a solenoid valve, controlled by an internal thermocouple. The cell was heated to 300-900°C (temperatures reached within 1 minute) for 2 to 5 minutes with helium passing through the cell at 15 ml/min, controlled with a Sierra Instruments Smart trak™ gas flow controller. Gas was measured using a Ritter MGC-10 gas meter. Twelve 2-ml gas trapping loops, in-line between the reaction cell and the gas meter, collected gas samples for analysis. Gas analysis was performed by GC fitted with a TCD operating at 220°C. The liquid was collected in a -78°C dry ice/ethanol trap and its mass determined gravimetrically. The liquid fraction was analyzed by GC-mass spectrometry and HPLC with a refractive index detector. Char was determined by combustion of the solids removed from the cell after the reaction. All mass lost during heating in air to 650°C was taken to be char. The char was characterized by temperature programmed oxidation on a Quantachrom AS-1 with TCD and solid state **13C NMR. Preliminary results showed that group II metal-modified Y-54 and ZSM-5 zeolites, water gas shift catalysts, and transition metal-modified aluminum oxides affected the speciation of the liquid and gas fractions during the pyrolysis of lipids and lignocellulosics. Versus sand, the standard heat transfer material in fluidized-bed reactors, Mo-Al2O3 increased the liquid fraction during lipid pyrolysis and concurrently increased the quantity of H2 in the gas fraction. The acidic zeolite H-ZMS-5 reduced the amount of short and long chain alkanes obtained from lipid pyrolysis and dramatically increased the liquid fractions’ aromatic content in the form of BTXs.