Desavath V. Naik

Effective catalytic conversion of cellulose into high yields of methyl glucosides over sulfonated carbon based catalyst.

An amorphous carbon based catalyst was prepared by sulfonation of the bio-char obtained from fast pyrolysis (N(2) atm; ≈ 550°C) of biomass. The sulfonated carbon catalyst contained high acidity of 6.28 mmol/g as determined by temperature programmed desorption of ammonia of sulfonated carbon catalyst and exhibited high catalytic performance for the hydrolysis of cellulose. Amorphous carbon based catalyst containing -SO(3)H groups was successfully tested and the complete conversion of cellulose in methanol at moderate temperatures with high yields ca. ≥ 90% of α, β-methyl glucosides in short reaction times was achieved. The methyl glucosides formed in methanol are more stable for further conversion than the products formed in water. The carbon catalyst was demonstrated to be stable for five cycles with slight loss in catalytic activity. The utilization of bio-char as a sulfonated carbon catalyst provides a green and efficient process for cellulose conversion.

Catalytic cracking of jatropha-derived fast pyrolysis oils with VGO and their NMR characterization

Lignocellulosic biomass-derived fast pyrolysis oils are potential second-generation bio-fuels towards the reduction of greenhouse gas (GHG) emissions and carbon foot prints. This study pertains to co-process the Jatropha-derived heavy or tar fraction of fast pyrolysis oil (FPO) with vacuum gas oil (VGO) and hydrodeoxygenated fast pyrolysis oil (HDO) with VGO in a standard refinery fluid catalytic cracking (FCC) unit. The crude fast pyrolysis oil from Jatropha curcas is produced at 530 °C and atmospheric pressure using a bubbling fluidized bed pyrolyzer. The heavy fraction of FPO is hydrodeoxygenated over Pd/Al2O3 catalyst into HDO in an autoclave reactor at 300 °C and pressure of 80 bar. Further, HDO is co-processed with petroleum-derived VGO in an advanced cracking evaluation (ACE-R) unit to convert it into refinery FCC product slate hydrocarbons at a blending ratio of 5 : 95. FPO and HDO are characterized using 31P NMR, whereas FCC distillates, which are obtained on the co-processing of VGO with fast pyrolysis oil and HDO, are characterized using 1H and 13C NMR spectroscopy techniques. The 31P NMR analysis of crude FPO and HDO indicated that hydroxyl, carboxylic and methoxy groups are reduced during the hydrodeoxygenation of FPO. The experimental results at the iso-conversion level on the co-processing of HDO with VGO indicated a higher yield of liquefied petroleum gases (LPG), while lower yields of gasoline and LCO have been observed as compared to FPO co-processing with VGO and co-processing of pure VGO. Furthermore, the results of co-processing of FPO with VGO indicated that the yields of gasoline and LCO increased from 29 to 35 wt% and 14.8 to 20.4 wt%, respectively, whereas the yields of dry gas and LPG decreased from 2.1 to 1.4 wt% and 38.8 to 23.7 wt%, respectively, for an increase in the blending ratio from 5% to 20%. Therefore, it can be concluded that the co-processing of HDO with VGO in a FCC unit would be feasible in order to achieve a higher yield of LPG.

The production and evaluation of bio-oil obtained from the jatropha curcas cake.

Jatropha curcas cake has been studied to produce the bio-oil in a fixed bed pyrolysis unit (slow pyrolysis). The effect of pyrolysis temperature on the product yield and composition was investigated. The highest yield of bio-oil was obtained at 550°C with the heating rate of 5°C/min for the particle size of 0.5–0.8 mm. The physicochemical characteristics of optimum (maximum yield) bio-oil have been completed. The empirical formula of the bio-oil with a calorific value of 25.91 MJ/kg is C23.19 H53.53 N O10.78. The physicochemical characterization studies of the bio-oil showed that the bio-oil obtained from the jatropha curcas cake might be a valuable source for conventional fuel. Chemical composition of the bio-oil has been also investigated by 1H and 13C NMR spectroscopy.

Pyrolysis Oil Upgrading to Fuels by Catalytic Cracking: A Refinery Perspective

Pyrolysis oil produced using lignocellulosic material is an alternate source of energy. Pyrolysis is an attractive option for the conversion of lignocellulosic biomass into liquid, pyrolysis oil, and gaseous hydrocarbons and is considered as an emerging and challenging research area in the current scenario of renewable energy. To ensure the production of “drop-in” liquid hydrocarbons from biomass, there is urgency of integration of pyrolysis process with conventional petroleum refinery’s trillion dollars worldwide infrastructure. This will happen into reality only after going through the necessary actions and precautions at various process development stages, such as biomass pyrolysis, pyrolysis oil upgrading, and effective integration of biomass pyrolysis with refinery. Herein, the opportunities lie in upgrading of pyrolysis oil in petroleum refinery units such as catalytic cracking and steam reforming, is described. The challenges arise ahead of pyrolysis oil upgrading in fluid catalytic cracking (FCC) approach have been reviewed. The extent of pyrolysis oil coprocessing with vacuum gas oil (VGO) in a refinery FCC unit is discussed. The advances in biomass pyrolysis process integration schemes with petroleum refinery have been revealed.