基于COSMO-RS方法筛选易于乙腈/水分离的离子液体

采用COSMO-RS预测了乙腈+水+离子液体三元系统的汽液相平衡性质,讨论了不同离子液体对乙腈+水体系分离效果的影响,发现阴离子对乙腈+水分离效果的影响按照[OAc]>[Cl]>[DEP]>[DMP]>[Br]>[NO_3]>[EtSO_4]>[MeSO_4]>[DCA]>[BF_4]>[TfO]的顺序,而阳离子对乙腈+水分离效果的影响甚微,离子液体[EMIM][OAc]、[EMIM]Cl预计可以在分离乙腈+水的实际应用中得到较好的发展。

Vapor pressure measurement and correlation of acetonitrile + 1-butyl-3-methylimidazolium chloride, + 1-butyl-3-methylimidazolium tetrafluoroborate, and + 1-hexyl-3-methylimidazolium chloride

Vapor pressures were measured for acetonitrile+1-butyl-3-methylimidazolium chloride([C4mim][Cl]),+1-butyl-3-methylimidazolium tetrafluoroborate([C4mim][BF4])and+1-hexyl-3-methylimidazolium chloride([C6mim][Cl])at temperatures of 313 to 353 K by a quasi-static method.The experimental data for the binary systems were correlated by the non-random two liquid(NRTL)equation with an average absolute relative deviation(AARD)of within 1.84%.The results indicate that the three ionic liquids(ILs)can result in a negative deviation from the Raoult's law for the binary solutions containing acetonitrile,and the affinity between ILs and acetonitrile molecules follows the order[C4mim][BF4]+acetonitrile N[C4mim][Cl]+acetonitrile N[C6mim][Cl]+acetonitrile.

圣诞贺卡生产中纸板曲翘问题的研究

针对以250 g·m-2纸杯原纸为原料生产圣诞贺卡过程中出现的贺卡曲翘问题,开展专题研究。据已有文献及过往技术经验分析贺卡曲翘的可能原因,并就环境温湿度对纸板的伸缩性、含水量及曲翘情况进行了实验,同时对已变形纸板压平恢复情况展开了实验。实验表明:湿度增加10%含水量增加约1%;30%到90%湿度变化中,横向伸缩率增加约1%,纵向增加约0.2%;不同湿度改变曲翘变化可达2倍;温度变化对曲翘影响很小;自然平衡下在最初3 h内恢复70%曲翘。纸板曲翘主因是两表面含水量不同引起受力不均,而控制较低湿度范围(30%~60%),保持生产环境温湿度稳定能有效控制贺卡曲翘。