Influences of seed crystals on agglomeration phenomena and product purity of m-chloronitrobenzene crystals in batch crystallization

Changes in the fraction of agglomerates, agglomeration kinetics and product purity of m-chloronitrobenzene (CNB) crystals with the number and size of seed crystals were examined in batch crystallization experimentally, and in fluences of seed types (ground and well-defined) on agglomerate purities we re discussed. From the fraction of agglomerates and agglomeration kinetics, it was found that agglomeration occurred more frequently when the number o f seed crystals was larger and its size was smaller. The amount of purity d ecrease by agglomeration was smaller for the smaller number of seeds and fo r the larger ones. As the number of the elementary crystals constituting ag glomerates was smaller, the purity of agglomerates was higher. With ground crystals, more frequent agglomeration occurred and the purity of agglomerat es was lower than those for the well-defined crystals. (C) 2001 Elsevier Sc ience B.V. All rights reserved.