5.1. Process features
There are a number of important ways in which catalysts modify pyrolysis processes.1.Decomposition temperature of LC Biotin components may significantly decrease with a suitable catalyst.2.Catalysts affect network of reaction, i.e., deoxygenation which allows in situ upgrading of bio-oil by reducing oxygenated organic compounds. The presence of catalysts also reduces polymerization precursors (like multifunctional phenols) for stabilizing bio-oil.3.Decarboxylation, decarbonization and dehydration reactions may release more CO, CO2 and H2O when catalysts are employed.4.Catalysts promote formation of coke due to dehydration reactions (mainly due to high acidity of catalysts).
The effect of different catalysts on biomass pyrolysis and product distribution is shown in Table 3.
5.2. Biochar catalytic effect
6. Summary and future work
A number of mathematical and CFD modelling studies have been conducted for understanding the effect of different operating conditions such as biomass composition, particle size, reactor temperature, and residence time of volatiles. The models have been developed at different scales, i.e., kinetic, particle and reactor, for analyzing the parameters such as reaction mechanism, mixing/segregation behaviour of different phases. Studies have also been carried out for catalytic cracking of biomass and catalytic upgrading of pyrolysis oil for making its appropriate use as a source of energy.