l-cysteine-modified cellulose, its preparation method and application

Abstract

The invention discloses an L-cysteine-modified cellulose, as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) soaking cellulose powder in distilled water as a reaction solvent until the cellulose powder fully swells; (2) adding a ligand-L-cysteine to a product obtained in the step (1), adding a catalyst and a dispersing agent under a nitrogen protection condition, keeping the reaction temperature at 45-90 DEG C and carrying out stirring reaction for 12 hours, wherein the molar ratio of the L-cysteine to the cellulose powder is (2-5) to 1; and (3) filtering a product obtained in the step (2) to obtain a filter cake, washing the obtained filter cake with the reaction solvent until the colorless phenomenon appears, drying at 50 DEG C in vacuum until the weight is constant, so as to obtain the L-cysteine-modified cellulose. The L-cysteine-modified cellulose and the preparation method thereof, disclosed by the invention, are simple and low in cost, and have the relatively high selective adsorption on Se (IV) ions in food.

Description

technical field [0001] The invention relates to a production method of a novel modified cellulose, in particular to a kind of L-cysteine-modified cellulose which has selective adsorption to heavy metal ions in food, good adsorption performance and reusability, and its preparation method and application. Background technique [0002] With the development of modern analytical techniques and analytical instruments (such as ICP-MS, ICP-AES, and AAS, etc.), the detection limit of elements has been greatly reduced. For example, metal ions at the ppt level can be detected using ICP-MS. However, in the analysis process of trace and ultra-trace heavy metal elements, due to the interference of a large number of coexisting elements, direct determination is often difficult. Although some analytical instruments have high selectivity and sensitivity, the high detection cost limits their domestic use. Popularization of production testing in small food enterprises. It is of great research...

AI Technical Summary

Problems solved by technology

There are many methods for the separation and enrichment of heavy metals, but most of the existing methods for the analysis of heavy metals in food have shortcomings such as low anti-interference, poor selectivity, and high analysis costs.

For example, the cost of materials used in the membrane separation method is high; the cost of ion exchange resin is low, and the treatment method is simple to operate but the selectivity is poor; the more common chemical precipitation method, the precipitant used is often expensive, and it is used in the treatment of lower concentrations. Does not work well with metal ions

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