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In this study, by means of chromatography - mass spectrometry , chromatography analysis , as well as acid-base titration analysis to establish the qualitative and quantitative analysis method of the experimental product , and verify the reliability of the analytical methods . Isobutylene and acetic acid as the raw material , the use of A , B, C three strong acid cation exchange resin as a catalyst for the synthesis of tert-butyl acetate , the effects of the reaction pressure , airspeed, reaction temperature , the ratio of raw materials and other process conditions on the synthetic acetic acid tert Ester and A15 catalyst experimental results were compared. The results indicate that the various process parameters for dissolving isobutylene , tertiary butanol selectivity impact is not obvious , in the case of isobutene as a liquid , the reaction pressure on the acetate , conversion rate , TBA selectivity oligomer selective effect is small , acid en - ratio, reaction temperature on the esterification reaction significantly ; C catalyst esterification effect is the best , the optimum process conditions : reaction pressure of 1.0 ~ 1.2MPa airspeed 4h-1, acid ene 4 : 1, reaction temperature of 17 to 23 ° C . The isobutylene conversion rate can reach 90% , tert-butyl acetate selectivity of up to 90% , less than 10% of the oligomer selectivity . Adding a certain percentage of water in acetic acid feedstock , or tert-butanol, can be effectively suppressed the formation of isobutylene oligomers , thereby increasing the selectivity of the t-butyl acetate . Plus t-butanol method to improve TBA selectivity , reducing the selectivity of isobutylene oligomers is more effective. Tert-butanol feedstock suitable addition amount from 5.0 to 6.0 % , selectivity of TBA at this time is close to 100 % selectivity of isobutylene oligomers can be reduced to 1.5% . Analysis of the nature of the C, B, A , and A15 catalyst , the results showed that the exchange capacity of the resin A and B , is slightly larger than C with A15 resin , specific surface area , acid strength is far less than A15 and C resin ; from esterification reaction effect , A15 , and C esterification reaction effect is better than A and B , and the large surface area, and high acid strength of the catalyst has a better effect the esterification reaction ; nature analysis , four resin catalyst for esterification the order of reactivity is of C ≈ A15 gt; B gt; A, in good agreement with the experimental results .
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