The maleic anhydride manufacturer will explain the method of identifying maleic anhydride and maleic acid:

1、称取大约相同的量，用水溶解后，再用碱滴定，消耗碱多的是酐，消耗碱少的是酸。

1. Weigh about the same amount, dissolve it with water, and then titrate it with alkali. Anhydride consumes more alkali and acid consumes less alkali.
 

2、或取少量相同量的样品溶解于水，用pH计检测，pH值低的是酐，pH稍高的是酸。

2. Or take a small amount of the same amount of sample to dissolve in water and test it with a pH meter. The anhydride with low pH value and the acid with slightly higher pH value.

3、用熔点检测也可以，酐与酸的熔点不同。顺酐约52~53℃，顺酸约130℃。

3. It can also be detected by melting point. The melting point of anhydride and acid is different. Maleic anhydride is about 52 ~ 53 ℃, and maleic acid is about 130 ℃.

 

4、^简单的办法，找一小块不锈钢片，将两种样品各放一点于钢片两侧，用打火机在两个样品中间加热，先液化并挥发的是顺酐。

4. ^ a simple way is to find a small piece of stainless steel sheet, put a little of the two samples on both sides of the steel sheet, and heat them with a lighter. Maleic anhydride is liquefied and volatilized first.