Effects of FAU Zeolites on the Crystallization of Chloronitrobenzenes above the Eutectic Composition

Crystallization has been used for the separation of chloronitrobenzene or CNBs, which are isomeric substances (o-, mand p-CNB) and important intermediates in chemical productions. Effects of feed composition on the crystallization of m- and p-CNB was first studied. The results conform to the binary phase diagram of m- and p-CNB. After that, effects of FAU zeolites (NaX, CaX, BaX, NaY and CaY) above the eutectic composition (63.5 and 65.0 wt% m-CNB in the feed) was also investigated. The results showed that the FAU zeolites significantly affected the precipitates, the composition of which was shifted from being rich in m-CNB to rich in p-CNB. Effects of the number of FAU zeolites on the precipitate composition was then studied. The results revealed that the precipitates from the lower number of the zeolites had higher p-CNB purity than those from the higher number of zeolite.

Authors:

• Jeeranun Neaungjumnong
• Sasikarn Yairit
• Sudarat Pattanapaiboonkul
• Pramoch Rangsunvigit
• Santi Kulprathipanja

Keywords:

• Chloronitrobenzenes
• crystallization
• separation
• eutectic

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