The Research And Development Of Bio-oil Co-processing Technology

Co-processing is a promising process of bio-oil refinery,which can be implemented on a certain scale.Since the technology is still on its preliminary stage,it’s important to study on the co-processing catalyst and the effects of feedstock on the reaction path.Four kinds of catalysts:HY/K,5A/K,HZSM-5/K,HZSM-5/MK were made with molecular sieve as active component and kaolin as carrier.The effects of active component,pore size and acidity of catalyst on bio-oil catalytic cracking were investigated in the fixed bed reactor with guaiacol as model compound.The results show that:HZSM-5 has higher catalytic selectivity due to its strong acidity and mesoporosity.At the same time,the addition of macroporous kaolin as carrier could reduce the coke yield and improve the quality of oil.The yields of coke and aromatic hydrocarbon are higher;and the highest mononuclear aromatics yield of 72.07%and lowest coke yield of 7.82%were obtained with HZSM-5/MK as the catalyst.Etherl acetate and guaiacol were selected as model compounds to co-process with paraffin oil respectively to investigate the effect of co-processing on reaction path through the comparison of products.It was found that decarboxylation,dehydration and alkylation are the main reaction in the ethyl acetate catalytic cracking process;alkylation and isomerization are the main reaction in guaiacol catalytic cracking process;co-processing promotes the hydrogen transfer and alkylation reaction,thus the liquid yield can be increased to 85.09%and 85.52%respectively.To study the influence of feedstock on co-processing,the bio-oil co-processed with methanol,diesel oil,and paraffin oil respectively.It can be concluded that methanol can promote the deoxygenation and decrease the coke yield,however the refined oil yield doesn’t change;with paraffin oil and diesel oil as co-process feedstock with bio-oil,the refined oil yields have a significant increase,the yields of coke are lower than predicted;diesel is prior to paraffin oil and methanol in the effect of deoxygenation.Bio-oil was co-processed with paraffin oil and diesel respectively under the blending ratio of 20%,and the liquid yields were 79.65%and 80.51%.