The determination of boron content in the borax - Shanghai xin chemical industry

borax, also known as sodium tetraborate, is a typical alkali weak acid salt, in appearing in alkaline aqueous solution. So, how much the boron content of borax is how to measure? We can learn about the today.

how many of the boron content in the detection of borax, chemical properties analysis of borax, obtained by direct titration method and indirect titration.

direct titration: borax boric acid ions in the aqueous solution of hydrolysis, attribute decision because of its material itself, the finish is the boric acid generated is very weak. Thus generated according to the concentration of boric acid to calculate the PH of the solution, select the appropriate indicator to determine the reaction end point, but the direct titration method is easy in borax to determine hydrogen carbonate as boric acid salt, therefore its measurement results easily on the high side.

indirect titration: now, through the analysis of borax usually adopt the method of indirect titration for determination of the so-called indirect measurement, all is to use the boric acid, borax and into boric acid, and even add too much acid, come out the inside of the carbon dioxide. With the principle of acid and alkali neutralization to neutralize excess acid, can join a polyol boric acid reinforcement for large complex acid electrolytic constant, then choose the appropriate indicator to indicate the end.

analysis shows that the analysis of the boron content in the borax contains two types of acid-base titration, one is made into boric acid, borax and borax, quantitative determination of boron content in the so called borax can be summed up in the determination of boron content in boric acid.