摘要
精制(一称提纯)为的是要获得纯度较高的物质。市售试剂或多或少含有从制备中带来的杂质。如果杂质的量足以影响使用,则在使用前予以精制,使其杂质量减少至可允许的程度。例如欲测定三元络合物的组成比时,如果其中任一成分不纯,自然要影响组成比的可靠性。又如用不纯物质测定物理常数和化学性质均属白费精力,反而给文献添加困扰。再举一例,化学法测定原子量系依据化合比,所以所用试剂包括水均需在实验室中用市售分析纯试剂自行精制。自然,精制是无止境的,但纯度越高,价格越昂。因此在化学试验中。
This article reviews the literature from ca. 1957, when xylenol orange was first synthesized, to 1983 covering its separation from semixylenol orange together with their purification. Methods for purification including (1) chromatography with cellulose powder column, (2) that with DEAE-cellulose column, (3) that with Nylon powder column, (4) thin-layer chromatography (TLC) together with preparative TLC, (5) high performance liquid chromatography, (6) gel filtration, and (7) miscellaneous devices are surveyed and discussed. Eighteen references.
出处
《化学试剂》
CAS
1985年第6期358-361,314,共5页
Chemical Reagents
