Preparation method and application of crosslinking-enzymolysis composite superfine modified starch adsorbent

Abstract

Provided is a preparation method of a crosslinking-enzymolysis composite superfine modified starch adsorbent. The method comprises the steps that 1, corn, sweet potatoes and potatoes are superfinely ground into superfine starch with the granule size of 10-50 micrometers through a superfine grinder separately; 2, the three kinds of superfine starch are mixed to be uniform according to the mass ratio of 1:4:3, water is added into the materials, stirring is conducted, and starch emulsion is obtained; 3, the pH of the starch emulsion is adjusted to be 7.5-8.5, a certain amount of sodium tripolyphosphate solution is added, and crosslinking is conducted for 1-1.5 h at the temperature of 75 DEG C-80 DEG C; 4, centrifugal dewatering is conducted on crosslinked starch emulsion, the dewatered starch emulsion is washed with deionized water, and freeze drying is conducted; 5, the crosslinked starch is added with water and blended into starch emulsion again, the pH is adjusted to be 6.5-7.5, alpha-amylase and isoamylase are added, and an enzymolysis reaction is conducted for 12-15 h at the temperature of 50 DEG C; 6, the starch emulsion subjected to enzymolysis is centrifuged, washed and dried and then sieved through a 40-100-mesh sieve, and the crosslinking-enzymolysis composite superfine modified starch is obtained. The modified starch significantly increases the specific surface area of porous starch, improves the mechanical strength of the porous starch and improves the adsorption capacity of the porous starch on harmful ingredients, especially, heavy metal elements.

Description

technical field [0001] The invention belongs to the technical field of adsorbents, and in particular relates to ultrafinely modified starch through a cross-linking-enzymolysis method, which is used as an adsorbent in industrial waste water containing heavy metal ions and pollutants. Background technique [0002] Starch is a polysaccharide natural polymer compound formed by the condensation of glucose. It is a renewable substance with the most abundant sources in nature. It can be degraded and will not pollute the environment. There are a large number of reactive hydroxyl groups in its molecular chain, which provides a structural basis for the modification of starch. Modified starch is based on the inherent characteristics of natural starch. In order to improve the performance of starch and expand its application range, physical, chemical or enzymatic treatment is used to introduce new functional groups on starch molecules or change the size and size of starch molecules. The...

AI Technical Summary

Problems solved by technology

However, the unsuitable enzymatic method will cause the disadvantages of porous starch such as small specific surface area, small pore volume, shallow pore depth, poor particle firmness, and easy breakage. These problems seriously affect the adsorption effect and practical application of porous starch.

Images