| In this paper,the zeolite molecular sieve catalysts was screened and then modified by metal modification and composite modification,exploring the effect of modification,in order to provide guidance for further research.The main findings of the paper are as follows:?1?Reacted on laboratory-made small fixed-bed,investigate the Jatropha oil catalytic cracking reaction characteristics with ZSM-5?silica-alumina ratio of 25,38,50?,?,MCM-41 and HY Catalytic.According to the liquid product yield and quality to establish the optimal reaction temperature and mass space velocity.The results show that the microporous ZSM-5 series molecular sieve has obvious aromatization characteristics and acid reduction.On the condition of ZSM-5?25?,a temperature of475°C and a mass space velocity of 5.23 h-1,the effect of Jatropha oil catalytic cracking to bio-based fuel oil is the best,with the acid value 4.2 mgKOH·g-1,the liquid product yield 42.20%,the aromatic compound 92.56%;the microporous molecular sieve HY has poor effect on decarboxylation and aromatization.On the condition of 475°C and 6.99h-1,the effect of HY is best,with the liquid product yield54.36%,the acid value 14.06mgKOH·g-1,and the aromatic compound content 45.58%;?molecular sieve has better acid-reducing effect than HY,but the yield is not high,the catalytic cracking effect of Jatropha oil is poor;the liquid product yield of mesoporous MCM-41 molecular sieve is high.On the condition of 475°C and 6.99h-1,the effect of MCM-41 is the best,with the liquid product yield 57.14%,the liquid product acid value 15.2mgKOH·g-1,and the aromatic compound content 64.75%.Comprehensive analysis showed that the best catalytic was ZSM-5 molecular sieve with a silica to alumina ratio of 25.?2?The ZSM-5 zeolite was modified by excess impregnation method to synthesize Fe/ZSM-5 zeolite.The structure was characterized by XRD,BET,SEM,TEM and XRF,and evaluation the Fe/ZSM-5 zeolite by Jatropha oil catalytic cracking performance.The results show that the Fe/ZSM-5 zeolite modified by alkali treatment with 1 mol·L-11 sodium carbonate solution and 0.1 mol·L-11 ferric nitrate solution is best,and has little change in specific surface and crystal structure,iron can also uniformly dispersed on the parent ZSM-5 molecular.The catalyst exhibits superior catalytic performance.When the temperature is 475°C and the mass space velocity is 5.23 h-1,the liquid product yield is 78.84%,and the liquid product yield is obvious improved.?3?The core-shell multistage pores ZSM-5/MCM-41 composite molecular sieves were prepared by hydrothermal synthesis method,characterized by XRD,BET and SEM,and analysis the effects of alkali treatment time and templating agent dosage on the ZSM-5/MCM-41 catalytic performance of Jatropha oil catalytic cracking reaction.The results show that when the alkali treatment time was 1 hour and the dosage of MCM-41 template was 90%?mass ratio of CTAB to ZSM-5?,the synthesized composite molecular sieve had the best catalytic cracking effect on Jatropha oil.At this time,the crystal growth of the composite molecular sieve is relatively complete,and the distribution of MCM-41 on the surface of ZSM-5 is relatively uniform.Under the conditions of 475°C and 5.23h-1,the test of catalytic cracking of Jatropha oil has good acid-reducing performance,the liquid product yield is 15.88%,the acid value is 1.5mgKOH·g-1,and the density is 824.9Kg·m-3,the coking and loss is 9.0%,and the acid value of the liquid product can be reduced.In this experiment,ZSM-5?25?was modified by different methods to improve the bio-based fuel oil yield and quality,which is prepared by catalytic cracking of Jatropha oil.Provide data support for the preparation of bio-based fuels with metal modified and composite modified ZSM-5 catalytic. |
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