Urea was dissolved into mixture of m/p-cresol(m/p=59.1/40.9)upon heating to 80℃.The resulting solution was cooled spontaneously to 40℃,then further to a designated temperature in an even speed with stirring with eve...Urea was dissolved into mixture of m/p-cresol(m/p=59.1/40.9)upon heating to 80℃.The resulting solution was cooled spontaneously to 40℃,then further to a designated temperature in an even speed with stirring with even dropping of toluene.Co-crystal of urea and m-cresol was thus formed as white precipitate,which was then isolated by filtration.Pure m-cresol was obtained by distillation of oil layer that was the upper layer of hydrolyzed decomposition of filtrating cake.Effects of solvent,material ratio,temperature on the yield and the purity were investigated.m-Cresol with purity of 99.0% and yield of 73.9% is obtained at an optimized condition at urea/(m/p)-cresol=23g/50ml,final temperature=-15℃,time=110min,and dropping of 150ml toluene.The existence of co-crystal of urea and m-cresol was verified by IR spectroscopy.The product purity was assayed by GC.展开更多
文摘Urea was dissolved into mixture of m/p-cresol(m/p=59.1/40.9)upon heating to 80℃.The resulting solution was cooled spontaneously to 40℃,then further to a designated temperature in an even speed with stirring with even dropping of toluene.Co-crystal of urea and m-cresol was thus formed as white precipitate,which was then isolated by filtration.Pure m-cresol was obtained by distillation of oil layer that was the upper layer of hydrolyzed decomposition of filtrating cake.Effects of solvent,material ratio,temperature on the yield and the purity were investigated.m-Cresol with purity of 99.0% and yield of 73.9% is obtained at an optimized condition at urea/(m/p)-cresol=23g/50ml,final temperature=-15℃,time=110min,and dropping of 150ml toluene.The existence of co-crystal of urea and m-cresol was verified by IR spectroscopy.The product purity was assayed by GC.