Method for preparing mercapto cotton

Abstract

The invention belongs to mechanical synthesis technology field, which is a method for producing mercapto cotton. The character lies in: it uses sulfo-glycollic acid, tetrahydrofuran and concentrated sulfuric acid as reaction reagent, the volume proportion of each kind of reagent is: sulfo-glycollic acid: tetrahydrofuran: concentrated sulfuric acid= 1:1:0.002, the quantity of reaction reagent and absorbent cotton is: adds in 15 g absorbent cotton into 100ml reaction liquid. They are placed for 45-50 hours under temperature of 38-40 degrees, uses G1 filter crucible to filter the reaction liquid in mercapto cotton, and uses evaporated water to clean it to neutrality, and then filter out the water, adds in absolute ethyl alcohol to absorb the residual water. The invention uses more less reaction reagent, the content of mercapto is high, and the mechanical intensity is good.

Description

technical field [0001] The invention belongs to the technical field of chemical synthesis and relates to the preparation of mercapto cotton, in particular to a method for preparing mercapto cotton. technical background [0002] Mercapto cotton is widely used in analytical chemistry, it can quantitatively adsorb Hg in aqueous solution under certain conditions 2+ 、Ag + 、As 3+ Wait for nearly 20 kinds of metal cations to achieve the effect of enriching metal ions. At the same time, according to the adsorption performance of various ions on mercapto cotton and the different elution conditions, the separation of different ions is realized. [0003] Mercapto cotton is synthesized by grafting thioglycolic acid on cotton fibers, and there are two methods for preparing mercapto cotton in the prior art: [0004] (1) In a jar, add 50 ml of thioglycolic acid, 35 ml of acetic anhydride, 16 ml of 36% acetic acid, 0.15 ml of concentrated sulfuric acid and 5 ml of distilled water in sequ...

AI Technical Summary

Problems solved by technology

Acetic anhydride can react with water in thioglycolic acid (generally thioglycolic acid contains ≤10% water) to generate acetic acid, which releases a lot of heat and makes the temperature of the reaction system rise rapidly to 60-70°C. If it is not properly controlled , it is easy to break the mercapto cotton, making the mercapto cotton unusable

In the prior art, after washing the mercapto cotton to neutrality, although it has been filtered by suction, there is still some water in the cotton, and it takes about 10 hours or more to dry completely in a 40°C oven, during which the hydrolysis of the mercapto cotton and the mercapto Oxidation and other reactions will reduce the mercapto group content and performance of the product

And above two kinds of technologies all adopt thioglycolic acid, acetic anhydride, 36% acetic acid, sulfuric acid to be main reaction reagent, the ratio is slightly different, and used reagent has four or five kinds, and kind is many, and process is more complicated, and operation difficulty is big, longer preparation time