Lignins are generally used as a low grade fuel in the pulp and paper industry. In this work, pyrolysis of Alcell and Kraft lignins obtained from the Alcell process and Westvaco, respectively, was carried out in a fixed-bed reactor and in a thermogravimetric analyzer (TGA) using helium (13.4 mL/min/g of lignin) and nitrogen (50 mL/min/g of lignin), respectively. The reaction temperature was increased from 300 to 1073 K, while the heating rates were varied from 5 to 15 K/min. The gaseous products mainly consisted of H2, CO, CO2, CH4, and C2+. With increase in heating rate from 5 to 15 K/min both lignin conversion and hydrogen production increased from 56 to 65 wt % and from 25 to 31 mol %, respectively for fixed-bed pyrolysis reaction of Alcell lignin at 1073 K, whereas at the same condition the conversion and hydrogen production increased from 52 to 57 wt % and from 30 to 43 mol % for Kraft lignin. The distributed activation energy model (DAEM) was used to analyze complex reactions involved in the lignin pyrolysis process. In this model, reactions are assumed to consist of a set of irreversible first-order reactions that have different activation energies. This model was used to calculate the activation energy, E, the distribution of activation energy f(E), and the frequency factor k 0 for the pyrolysis of Alcell and Kraft lignins in a thermogravimetric analyzer (TGA). For the pyrolysis in TGA, the activation energies for Kraft and Alcell lignins varied from 129 to 361 kJ/mol with maximum distribution at ∼250−270 kJ/mol and from 80 to 158 kJ/mol with maximum distribution at ∼118−125 kJ/mol, respectively.

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Glycerol is one of the by-products of transesterification of fatty acids to produce bio-diesel. Increased production of bio-diesel would lead to increased production of glycerol in Canadian market. Therefore, the production of hydrogen, syn gas and medium heating value gas is highly desirable to improve the economics of biodiesel production process. In this study, steam gasification of pure and crude glycerol was carried out in a fixed-bed reactor at the liquid hourly space velocity (LHSV) and temperature of 0.77 h -1 and 800°C, respectively. In this process, the effects of different packing materials such as quartz particle and silicon carbide were studied. Catalytic steam gasification was performed in the presence of commercial Ni/Al 2 O 3 catalyst in the range of steam to glycerol weight ratio of 0:100-50:50 to produce hydrogen or syngas when LHSV was maintained constant at 5.4 h -1 . Pure glycerol was completely converted to gas containing 92 mol% syngas (molar ratio of H 2 /CO & 1.94) and the calorific value of 13 MJ/m 3 at 50:50 weight ratio of steam to glycerol. Hydrogen yield was increased by 15 mol% via the steam gasification process when compared to pyrolysis process. The presence of catalyst increased further the production of hydrogen and total gas in case of both pure and crude glycerol indicating their strong potential of making hydrogen or syngas. Maximum hydrogen, total gas and syn gas production of 68.4 mol%, 2.6 L/g of glycerol and 89.5 mol% were obtained from glycerol using Ni/ Al 2 O 3 catalyst at temperature and steam to glycerol ratio of 800°C and 25:75, respectively.

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A systematic study has been conducted in a trickle-bed reactor using a commercial NiMo/ Al 2 O 3 catalyst to understand the effects of different variables such as H 2 S concentration in the feed by adding different amount of butanethiol, reaction pressure, temperature, liquid hourly space velocity (LHSV), and H 2 /feed ratio on the hydrodenitrogenation (HDN) of typical basic (acridine) and nonbasic (carbazole and 9-ethylcarbazole) nitrogen compounds present in heavy gas oil. The HDN conversion of basic compound was higher than that of nonbasic compounds at all butanethiol concentrations (0-4 wt %) in the feed. The HDN conversion of acridine was 98-99 wt % at 355-400 °C, whereas, with an increase in temperature from 355 to 400 °C, the conversion of carbazole and 9-ethylcarbazole increased somewhat from 92 to 95 wt % and from 94 to 97 wt %, respectively. Pressure (1120-1420 psig) had no effect on the HDN conversion of basic and nonbasic nitrogen compounds. Also, an increase in LHSV did not have a significant effect on the conversion of acridine and 9-ethylcarbazole. However, the conversion of carbazole increased from 92 to 99 wt % with a decrease in LHSV from 2 to 0.5 h -1 . The increase in H 2 /feed ratio from 200 to 800 mL/mL caused a significant increase in conversion of carbazole from 90 to 98 wt %. The present studies showed no steric hindrance effect of the alkyl group present in 9-ethylcarbazole.

In this work, a systematic study has been conducted to optimize the process conditions and to evaluate kinetic parameters for hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) of heavy gas oil derived from Athabasca bitumen using NiMo/Al 2 O 3 catalysts containing boron (B). In the catalyst, the concentrations of boron were varied from 0 to 1.7 wt %. Experiments were performed in a trickle-bed reactor at the temperatures, pressures, and liquid hourly space velocities (LHSVs) of 340-420 °C, 6.1-10.2 MPa, and 0.5-2 h -1 , respectively. H 2 flow rate and catalyst weight were maintained constant at 50 mL/min and 4 g, respectively, in all cases. Statistical analysis of all experimental data was carried out using ANOVA to optimize the process conditions for HDN and HDS reactions. Kinetic studies for HDN and HDS reactions were studied within the temperature range of 340-400 °C using a power law model as well as the Langmuir-Hinshelwood model. The power law model showed that HDN of heavy gas oil follows first-order kinetics while the HDS process follows 1.5-order kinetics. The activation energies for HDN and HDS reactions from power law and Langmuir-Hinshelwood models were 75 and 87 kJ/mol and 110 and 159 kJ/mol, respectively.

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