近来有同仁问到,“一定浓度的碱性乙醇/甲醇怎么配制?一定浓度的氢氧化钾乙醇/甲醇溶液怎么配制?乙醇制氢氧化钾滴定液怎么配制?”。几个问题其实归结起来也就是一个问题“一定浓度乙醇制氢氧化钾滴定液怎么配制?”,弄清这点之后,类似碱醇溶液的配制方法便可轻松搞定。
Recently, a colleague asked, "how to prepare a certain concentration of basic ethanol / methanol? How to prepare a certain concentration of potassium hydroxide ethanol / methanol solution? How to prepare potassium hydroxide titrant from ethanol. In fact, several problems can be summed up as "how to prepare potassium hydroxide titrant with a certain concentration of ethanol?", After understanding this point, the preparation method similar to alkali alcohol solution can be easily done.
氢氧化钾生产厂家现将乙醇制氢氧化钾滴定液(0.5mol/L或0.lmol/L)和甲醇制氢氧化钾滴定液(0.lmol/L)的配制和标定方法分享给大家。
Potassium hydroxide manufacturers now share the preparation and calibration methods of potassium hydroxide titrant (0.5mol/l or 0.lmol/l) made from ethanol and potassium hydroxide titrant (0.lmol/l) made from methanol.
从氢氧化钾生产厂家介绍的配制过程来看,配制过程中,取用的氢氧化钾量较理论量略大,之所以这样做,是因为氢氧化钾本身在乙醇中的溶解度很大,但是氢氧化钾在空气中会吸收二氧化碳,而且氢氧化钾吸水能力也很强,再者配制好的碱醇溶液同样会吸收空气和溶液中的二氧化碳而消耗溶液中的碱。
According to the preparation process introduced by the potassium hydroxide manufacturer, the amount of potassium hydroxide used in the preparation process is slightly larger than the theoretical amount. The reason for this is that the solubility of potassium hydroxide itself in ethanol is very high, but potassium hydroxide will absorb carbon dioxide in the air, and the water absorption capacity of potassium hydroxide is also very strong, Moreover, the prepared alkali alcohol solution will also absorb the air and carbon dioxide in the solution and consume the alkali in the solution.
基于以上考虑,配制过程中应多称一些氢氧化钾才能达到需要的碱浓度,但是很难定向配制到具体的浓度,所以氢氧化钾生产厂家配制的碱醇溶液临用前应标定浓度,然后通过换算得到具体的碱浓度。
Based on the above considerations, more potassium hydroxide should be weighed in the preparation process to achieve the required alkali concentration, but it is difficult to prepare the specific concentration directionally. Therefore, the alkali alcohol solution prepared by potassium hydroxide manufacturers should calibrate the concentration before use, and then obtain the specific alkali concentration through conversion.