含水环己酮中RDX的结晶介稳特性

Crystallization Meta-stable Characteristics of RDX in Water-containing Cyclohexanone

为获得高品质、粒度均匀的大颗粒黑索今(RDX)晶体,研究了RDX在含水环己酮混合溶液中的结晶介稳特性。利用光谱法测定RDX在该溶液中的平衡浓度和超溶解度,得到了RDX在该溶液中的结晶介稳区宽度,建立了平衡浓度和超溶解度模型。结果表明:当溶液温度升高时,RDX的介稳区宽度变窄。当含水量为8%时,在低温区和高温区的介稳区宽度均值分别为16.4℃和15.0℃,含水量为4%时,分别为19.1℃和14.0℃;当超溶解温度高于58℃、含水量从4%增加到8%时,溶液的介稳区更宽。利用获得的介稳特性,在介稳区间加入RDX晶种结晶生长得到了约2 mm的透明、表面圆润、接近球形的高品质RDX。

In order to obtain large transparent spherical-shaped RDX crystal, the metastable characteristics of RDX in water-cyclo- hexanone mixture solvent were studied. Solubilities and super-solubilities of RDX in water-cyclohexanone solution were tested by spectroscopy method, and the metastable zone width of RDX solution was determined. The correlation among temperature, water content and metastable zone width was discussed in detail. It is found that the metastable zone width becomes narrow when temperature rises： the metastable width is 16.4 ℃ in low temperature zone while 15.0 ℃ in high temperature zone when the water content is 8%, and the meta-stable width is 19. 1℃ and 14.0 ~C respectively when the water content is 4%. When temperature of RDX solution is above 58 ℃, the metastable width changes more wider when water content increases from 4% to 8%. The large transparent spherical particle RDX crystal, with 2 mm size and smooth surface, is obtained by adding the RDX crystal seed into water-cyclohexanone-RDX solution, which is in metastable state.