论文部分内容阅读
在已知的定钾方法中,最适於分析天然钾盐及钾肥的无疑地是重量法,其中过氯酸盐法及亚硝酸钴法用得最广泛。过氯酸盐法最精确,虽然被推荐於作大规模分析钾盐及工业盐水,然而过氯酸的缺乏常常限制了它的应用。亚硝酸钴法属於不精确方法之列,原因是析出的沉淀没有恒定的组成,视沉出的条件和试验溶液中K:Na的比量而定。此法在实际上只适用於不要求特别精确的场合。文献中所载的其他方法,例如二苦酰胺盐法,磷钼酸盐法和四苯硼酸盐法,都由於种种原因而不能普遍应用以分析钾肥。
Of the known methods for determining potassium, the most suitable method for the analysis of natural potassium and potassium is undoubtedly the gravimetric one, wherein the perchlorate method and the cobalt nitrite method are the most widely used. The most accurate method of perchlorate, although recommended for large-scale analysis of potash and industrial brine, but the lack of perchloric acid often limits its application. Cobaltous nitrite is an inaccurate method because the precipitates do not have a constant composition, depending on the conditions of precipitation and the ratio of K: Na in the test solution. This method is in fact only applicable to the occasion does not require special precision. Other methods contained in the literature, such as the didecamidate method, the phosphomolybdate method, and the tetraphenylborate method, are not universally applicable for the analysis of potash for a variety of reasons.