Abstract:
Crystallization of chloronitrobenzenes (CNBs) with the presence of an adsorbent was investigated. Equilibrium binary component adsorption experiments of m-CNB and p-CNB on NaX, CaX, BaX, NaY, CaY, KY, Al2O3, SiO2, activated carbon and glass beads were performed. The results indicated that selectivity and adsorption of m-CNB and p-CNB depended on the adsorbent. Effects of feed composition on crystallization of m- and p-CNB were then studied with below, at, and above the eutectic composition (61.0, 62.9, and 63.5 wt.% m-CNB in the feed, respectively). In the experiments, the system was cooled by cooling water from 30 °C to crystallization temperature. The crystal composition was then measured by a gas chromatograph. The results conformed to the binary phase diagram of m- and p-CNB. On the other hand, the crystals from the feed with adsorbents were rich in p-CNB for both at and above the eutectic composition, and the crystals near the adsorbents had higher p-CNB purity than those far from the adsorbents.
