Study On Modified Cation Exchange Resin And Its Application For Butylene Hydration

Preparation route of SBA with catalyst of cation exchange resins is the main method of producing sec-butyl alcohol both at home and abroad.But in this process one-way conversion of n-butene rate is only about 6%,which seriously restricts the improvement of the economic efficiency.Therefore,the exploration of cation exchange resin modified to improve butene one-way conversion is of great significance.Firstly,this paper used D008 for sulfonyl chloride resins and modified resins.Compared to D008,the catalytic activity of modified resins,especially the resins modified with octadecyamine were improved to varying degrees.It was proved that,the resin that a small amount of -SO₄H modified with amid ocyanogen having controlled-length of carbon chain,can improve the activity.Based on the indirect process,we used PS to react directly with HSO₃Cl to produce sulfonic acid chloride resin.The factors that influence exchange capacity and sulfo-chloride degree of resin were also studied.The results showed the optimum conditionwas:feeds mole ratio(nHSO₃Cl/PS) was 8:1;reaction temperature was 80℃;reaction time was 10 h.We produced modified resin with different amination rate(0.6%～12.7%),using sulfonyl chloride resin(produced with the direct method) as the matrix and octadecylamine as amination reagents.Comparison of their catalytic activity showed that lower rate of amination resin for improving the catalytic activity was not obvious,but the activity decreased when amination rate was higher than 10%,and modified resin with amination rate of 6.8%had the strongest activity.The activity of modified resin under different hydration conditions was also discussed.The results indicated that the modified resin had better catalytic activity than D008 in different conditions;its activity stability and thermal stability were also better than D008.Furthermore,the mechanism of butene hydration catalyzed by modified resin was described. We suggest that hydrophobicity of the modified resin was improved after a small amount of -SO₄H was grafted by amine with controlled-length carbon chain.The concentration of C4 in water was increased so that butene one-way conversion was improved.