A novel process integrating vacuum distillation with atmospheric chlorination reaction for flexible production of tetrachloroethane and pentachloroethane

In this paper, we developed a novel process integrating vacuum distillation with atmospheric chlorination reaction(VD-ACR) to realize the flexible production of tetrachloroethane(TeCA) and pentachloroethane(PCA)from 1,2-dichloroethane(DCA). During the simulation, the distillation column and reactors were operated for separation and chlorination respectively under variable pressures and temperatures. It is interesting to note that VD-ACR processes producing pure TeCA or PCA can exhibit the similar configuration parameters after optimization, which enables the flexible production of TeCA and PCA with different molar ratios via changing operating parameters. The molar ratio of TeC A/PCA can be fine-tuned within the range of 0.9:0.1-0.1:0.9 through adjusting the amount of chlorine pumped into side reactors, giving rise to the increase of the heat duty of reboiler by five times. A pilot-scale experiment was then operated based-upon this VD-ACR process and the result matched well with the simulation. Therefore, the VD-ACR model presented in this study will be beneficial for the industrial-scale flexible production of TeCA and PCA from DCA.

Promoting di-isobutene selectivity over ZnO/ZrO_(2)-SO_(4) in isobutene oligomerization

Isooctane attracts great interest in recent years because of its promising potential as friendlyenvironmental gasoline,which is obtained by dimerization of isobutene with a hydrogenation step.Herein,a solid acid catalyst sulfated zirconia modified by ZnO was prepared.The oligomerization of isobutene had been investigated over ZrO_(2)-SO_(4) and ZnO(X)/ZrO_(2)-SO_(4) catalyst in order to find efficient catalysts for the production of isobutene oligomers.The presence of ZnO obviously enhanced the dimerization of isobutene and ZnO(X)/ZrO_(2)-SO_(4) exhibited the highest di-isobutene yield of 60%.Kinetic studies showed the higher trimerization-to-dimerization activation energy ratios of ZnO(X)/ZrO_(2)-SO_(4) than those of ZrO_(2)-SO_(4) from 353 to 393 K.In addition,reaction rate of dimerization was higher than trimerization over ZnO(X)/ZrO_(2)-SO_(4).The high L/B ratio manifested the capability to enhance the selectivity of C8 in isobutene dimerization.Furthermore,ZnO(X)/ZrO_(2)-SO_(4) exhibited stable conversion for the dimerization of isobutene.