Correlation between quantity of defect and supersaturation in RDX crystallization.pdf

C i s D C D 1 C f e p c i w i c P e o a 2 1 p s w 0 dchemical engineering research and design 8 8 ( 2 0 1 0 ) 1461–1466 Contents lists available at ScienceDirect Chemical Engineering Research and Design journa l homepage: www.e lsev ier .com/ locate /cherd orrelation between quantity of defect and supersaturation n RDX crystallization using -butyrolactone and water as olvent oo-Yong Kim, Kwang-Joo Kim ? rystallization Process Engineering Laboratory, Department of Chemical Engineering, Hanbat National University, SAN 16-1 ukmyung-Dong, Yuseong, Daejeon 305-719, Republic of Korea a b s t r a c t The crystallization of RDX (cyclotrimethylenetrinitramine) was carried out using cooling crystallization. Effect of cooling rate and antisolvent to solvent ratio on the inclusion was studied. Qualitative observation of internal crystal defects was performed by optical microscopy with matching refractive index. The quantitative amount of inclusions was determined bymeasuring concentration of solid. Effect of the cooling rate and the antisolvent to solvent ratio on supersaturation was investigated. The supersaturation affected significantly the inclusion of mother liquor inside the crystals. The higher supersaturation induced the more agglomeration, that caused the formation of the more inclusions inside RDX crystals. From morphological study, defect is formed in course of transformation from plate-like to polygon shape. An empirical correlation of the inclusion fraction of RDXwith the relative supersaturation was obtained. ? 2009 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Keywords: RDX; Defect; Supersaturation; Inclusion; Agglomeration; Crystallization Commercial grade cyclotrimethylene trinitramin (RDX)manu-. Introduction rystal quality is one of the important requirements in per- ormance of cyclotrimethylenetrinitramine (RDX), which is an xplosive compound. The quality is mainly affected by the urity of the crystals. It is well kn