Study On Sythesis Of Resorcinol From Oxidation Of M-diisopropylbenzene

Resorcinol, an important material of chemistry, is widely used in many fields, such as agriculture, dyestuff, dope, medicine, latex and electric-chemistry products. Now, resorcinol is mainly applied in latex industry, such as tyres, rubber pipe and adhesive for belt in automobiles. Experts forecast that with the rapid development of automobile industry, the output of resorcinol produced at home can't meet the demand in the market, and China will become the biggest resorcinol consumption city in the world.The preparation of resorcinol from m-diisopropylbenzene (DIPB) was studied in this paper. Mixed diisopropyl benzene was chose as the materials to compose high purity resorcinol by shape selective catalysis decomposition and vacuum distillation. Firstly,after reaction about 26 hours,DIPB was oxidized to the diisopropyl-benzene dihydroperoxide (DHP) and diisopropylbenzene hydroxyhydroperoxide (MHP) under anhydrous, non-alkaline conditions with oxygen at 90℃and the remaining unreacted DIPB was recycled to the feed stream for further hydroperoxidation. Then the hydroperoxidation products were extracted with 5%NaOH and stripped with methyl isobutyl ketone (MIBK) at about 80℃. The extracts were pretreated with hydrogen peroxide. Finally, the product dried with 4A sieves was decomposed in the presence of a catalyst boron trifluoride, and the rude resorcinol was gained by aether extracted.The results show that 35%hydroperoxide was achieved with initiator (azobisisobutyronitrile or m-diisopropylbenzene hydroperoxide). And under the air flow of 450 ml/min, the result is the best. The reaction results shoe that the MHP%with cleaned and uncleaned stacked materials were 66.78%and 54%after 27 h respectively. By using different alkalies, as NaHCO3 and NaOH, it shows that the MHP%is 64%with NaOH better than 44% with NaHCO3 after 27 h. The effection of reaction environment has been studied. In the condition of alkali with no water, the MHP%is achevied to 97.74%. In the oxidation of m-DIPB, the content of byproduct grows with the recycle times increasing, so it is necessary to remove the byprodudts from reaction solution before reused.In the decomposition of m-DIPB, the influence of reaction temperature,dosage of the catalyst and reaction time have been studied. The best condition is at 50℃, with 1μL BF3·CH3OCH3, for 40 min. At the same condition, DHP decomposes into resorcinol with pertreat of H2O2, and yield of resorcinol is 8.4%. The H2O2 pretreatment helps to improve the yield of resorcinol.