Biomass hydropyrolysis

M. Mozaffarian Hydrogen conversion in synthetic natural gas by biomass hydropyrolysis. ECN-CX—98-148, Netherlands Energy Research Foundation (ECN), Petten, December 1998. 

Hydropyrolysis process gives the higher degree of mixture conversion and higher yield of light liquids as compare to pyrolysis in an inert atmosphere. Observed in some cases non-additive effects indicate that the interaction between wood and plastic derived products takes place during mixture thermal treatment. The more pronounced synergistic effects were detected for hydropyrolysis process. Iron catalysts promote the formation of liquid hydrocarbons from biomass/plastic mixtures and influence on their coit sition. 

Utilization of wood-biomass residues as well as waste polymers is the important direction of recent research activities. It is known that direct catalytic liquefaction of plant biomass can be used to produce liquid fuels and chemicals [1,2]. Co-pyrolysis and co-hydropyrolysis processes have the potential for the environmentally friendly transformation of lignocellulosic and plastic waste to valuable chemicals. 

The influence of the process temperature on catalytic hydropyrolysis of biomass/plastic mixture was studied in the range 360 - 460 C. Fig. 3 shows that the highest conversion (91% wt.) of the pine wood / polyethylene mixture (1 1 weight ratio) was observed at 390 C - 430 C in the presence of activated haematite catalyst. Higher tenqieratures promote increased yields of char and gaseous products. At lower temperatures a reduced yield of distillate fraction was observed. In comparison with pyrolysis in inert atmosphere the increased yields of light hydrocarbon fractions (by 1.6 - 1.8 times) and increased degree of mixture conversion (by 1,2 time) were observed for hydropyrolysis process. 

According to GC data the gaseous products of polyethylene catalytic hydropyrolysis contain only alkanes. In the runs with polyethylene / biomass mixture at similar conditions carbons oxides were detected in gaseous products and the lower yields of Cj - C4 alkanes was observed,... 

GC-MC data show that the light liquid fractions of plastic / biomass co -hydropyrolysis contain mainly normal paraffins CrCij. Their content was 75% for pine wood / i-PP mixtures. Alkyl derivatives of benzene were also detected in the light liquid fractions. The content of unidentified substances was 15%, alkylbenzenes and alkytfriranes compounds - approximately 10% relative. 

The difference in the composition of gaseous and liquid products of hydropyrolysis of plastic and biomass / plastic mixtures indicates the interaction between intermediate products of natural and synthetic polymers thenrnl conversion. The iron ore catalysts increase the yields of light liquid products and olefinic hydrocarbons. Producing of... 

Meier, D., Bems, J., and Faix, 0. (1995) Pyrolysis and hydropyrolysis of biomass and lignins - activities at the Institute of Wood Chemistry in Hamburg, Germany. ACS Fuel, 1995, 298-303. 

IH [Integrated Hydropyrolysis and Hydroconversion] A process for converting biomass to hydrocarbon fuels using hydropyrolysis and hydroconversion. Developed by the Gas Technology Institute, Des Plaines, IL. Licensed to CRI, United States, which expected to commercialize it in 2014. 

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