Study On Catalytic Synthesis Of Di-iso-Propylbiphenyl And Tri-iso-Propylbiphenyl By Superacid

At present,the dye solvent for non-carbonic copying paper are mainly acromatic groups,alkynaphthalenes and the derivatives of diphenyl at home and abroad.Diisopropylnaphthalene(DIPN),diaryl ethane(SAS-296) and triphenyl hydride are used widely in industry. Among them DIPN has good perfromanee,but the expense is high;SAS-296 and triphenyl hydride are cheaper,waile the function is not outstanding.The author synthesized a new dye solvent for non-carbonic copying paper-the mixture of di-iso-propylbiphenyl and tri-iso-propylbiphenyl for the first time in home. With fixed content of di-iso-propylbiphenyl and tri-iso-propylbiphenyl, The mixture is odorlessness and achromic.lt has suitable viscosity and high solvent power ,what's more, the solvent is easily obtained and the cost is lower. It can be used to prepare non-carbonic pressure- sensitive copying materials. At the same time, the trace is clear and compact. We investigated two kinds of methods and concluded the second is practical in industry.The first method:The catalyst was superacid(concentrated sulfuric acid and waterless Aldl3) ,isopropyl was used as alkylation agent.The effects on yield of di-iso-propylbiphenyl and tri-iso-propylbiphenyl mixture were researched.when the molecular ratio of biphenyl and isopropyl is 1:2.5,the content of catalyst is 6%(according to the quality of biphenyl),under 85-90℃,after 2.5 hour,the mixture was alkalified, filtered, dried, and distilled successively ,the highest yield was 85%.The second method: The catalyst was prepared solid super acid (SO42-/Fe2O3,SO42-/ZrO2,SO4-/TiO2 et.al).Propene was used as the alkylation agent.The effects of reaction temperature ,reaetion time,the kind of catalyst ,the content of catalyst and the ratio of reaction materials on yield of reaction products were investigated. The result showed that The catalyst was SO42-/TiO2 solid superacid,under 180-210℃, the quality ratio of biphenyl and propene was about 1:1, the content of catalysts was 8% ,after 2 hour, the yield of di-iso-propylbiphenyland tri-iso-propylbiphenyl mixture was 91 %.The catalyst used in the first method was corrosive.The reaction solution needed settling, neutralization, several times of watering and dryiag, so lots of waste water was producted. In the second method, solid superacid was non-corrosive, and could be easily separated without polluted water.Comparing to the first method both the quality and yield of the product were better, so the second one was reasonable and economic.