Research On Preparation Of Biodiesel From Jatropha Curcas Oil

The development of today's society is getting faster and faster,and the rapid development of the world economy is accelerating the consumption of energy.The excessive use of petrochemical energy has also caused serious pollution to the global environment on which we live.Therefore,actively looking for environmentally clean energy has become an important topic of heat theory and research.Biodiesel as an environmentally friendly fuel has received extensive attention from scholars all over the world.In this paper,UiO-66 and its derivatives were synthesized by solvothermal synthesis.Different modulators were added to modulate the structure of zirconium-based MOFs.XRD,SEM and FT-IR were used to characterize the effects of different modulators and additions on the morphology and structure of zirconium-based MOFs.The results of characterization analysis show that the synthesized zirconium-based MOFs have structural defects,and the types of organic ligands and regulators have different effects on the formation of zirconium-based MOFs.The mixed modulators of acetic acid and hydrochloric acid can significantly improve the crystallinity of UiO-66.The benzoic acid in the same equivalent(30 eq)organic acid modulator has better control on the morphology of UiO-66,and the effect of improving the surface area and pore volume of formic acid is obvious.Theoretical analysis and related literature studies have obtained L acid in UiO-66 series MOFs.Two-step method for the preparation of biodiesel from Jatropha curcas oil was adopoted.Three new zirconium-based MOFs are selected as esterification reaction.The catalyst obtains an esterified oil,and then catalyzes the esterified oil with KOH to obtain a biodiesel having a methyl ester ratio of more than 99%.A Br(?)nsted acidic ionic liquid[HSO3-pmin]+[HSO4]-catalyst was synthesized and the structure was characterized by FT-IR.Using[HSO3-pmin]+[HSO4]-as catalyst to prepare biodiesel from jatropha curcas oil,the effects of reaction temperature,methanol to oil molar ratio,reaction time and catalyst dosage on biodiesel yield and acid value were studied.The relationship between acid value and yield was analyzed.The experimental results show that:at the reaction temperature of 70?,methanol to oil molar ratio is 25:1,the reaction time is 3 h,catalyst dosage is 3wt%of oil,the biodiesel having a yield of 90.13%and an acid value of only 0.049 mg KOH/g was obtained.The relative content of fatty acid methyl ester in biodiesel prepared under these conditions was determined by GC-MS to be as high as 100%.The ionic liquid has no obvious change in catalytic activity after being used 6 times.The B acidic ionic liquid was successfully loaded into three kinds of zirconium-based MOFs by impregnation method.The loaded zirconium-based MOFs maintained the original skeleton structure,the morphology and size did not change significantly,and the BET specific surface area was significantly reduced.The zirconium-based MOFs catalyzed the preparation of biodiesel from jatropha oil.Under the same conditions,PSH/UiO-66-NO2 was found to have the highest catalytic activity.Then PSH/UiO-66-NO2 was selected as the catalyst.The orthogonal experiment was designed.The results showed that the four reaction factors had significant effects on the biodiesel conversion rate:reaction time>catalyst dosage>reaction temperature>methanol to oil molar ratio.Under the optimal reaction conditions in orthogonal experiment,the conversion rate of biodiesel was 97.22%,the methyl ester rate was over 99%,and the three levels of methanol to oil molar ratio were more reasonable.After analysis,the optimal theoretical conditions were obtained:reaction temperature 70?,catalyst dosage 4%,methanol to oil molar ratio 25:1,reaction time 4 h,three verification tests of the best process,the conversion rate of biodiesel was greater than 97.22%.PSH/UiO-66-NO2 is not ideal for reuse due to shedding during ionic liquid reaction.