Ga、Zn改性ZSM-5对生物质热裂解产物单环芳烃选择性的影响OA

In order to solve the existing problem of bio-oil,which contains complex compounds and has a high oxygen content,research was conducted on biomass catalytic pyrolysis and reaction mecha-nisms to enhance the quality of bio-oil and improve the selectivity of monocyclic aromatics hydrocarbon(MAHs).Ga-modified ZSM-5 and Zn-modified ZSM-5 catalysts,prepared through the ion exchange method,were used to investigate the influence of SiO2/Al2O3 ratio and metal element type on the selec-tion of MAHs during corn stalk catalytic pyrolysis.Four different SiO2/Al2O3 ratios(30,40,50,and 60)were used for catalyst preparation.Pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)was used to analyze the products.The results indicated that Ga/ZSM-5 with a Si/Al ratio of 30 achieved the highest relative content of MAHs(19.02％),which was 1.38 times higher than that of the parent ZSM-5(30).Conversely,Zn/ZSM-5 with a Si/Al ratio of 40 exhibited the highest relative content of MAHs(22.18％),surpassing that of the parent ZSM-5(40)by 1.51 times.The SiO2/Al2O3 ratio significantly influenced the yield of xylene,naphthalene,and dimethylnaphthalene,while the metal element type also affected the yield of benzene,toluene,and indene.Based on the elemental structure of bio-oil,the relative content of aromatics,and the yield of MAHs,Zn/ZSM-5(40)per-formed better than Ga/ZSM-5(30).