Nano-iron-calcium-alginate-composite-film preparation method for hexavalent chromium removal

Abstract

The invention aims to provide preparation of a nano-zero-valent-iron-calcium-alginate-composite-film. The preparation of the nano-zero-valent-iron-calcium-alginate-composite-film comprises the steps that nano-iron is prepared by reducing ferric chloride using a tea extract solution based on bioanalysis, and the nano-iron is loaded onto an environment-friendly non-toxic and easily degradable calcium alginate film to prepare the nano-zero-valent-iron-calcium-alginate-composite-film. While the dispersibility and stability of the nano-iron are improved, the relative advantages of the nano-iron areremained, and the problem of nano-iron recycling is solved. The tea extract solution and the calcium alginate film can improve the dispersibility, stability and anti-oxidation ability of the nano-iron and can improve the removal effect of hexavalent chromium. At a certain film dosage, the higher the initial concentration of the hexavalent chromium, the slower the degradation rate, and the film dosage is opposite to the initial concentration of the hexavalent chromium. When the film dosage is larger, the degradation rate is higher. The advantages of the calcium alginate film with no pollutionto the environment, easy degradation and good load performance are utilized, the following results are measured at 25 DEG C, and it can be seen that the average particle size of particles is about 216nm.

Description

technical field [0001] The invention belongs to a method for preparing a nanometer iron-calcium alginate composite film by a biological method and using the nanometer iron-calcium alginate composite film to remove hexavalent chromium. Background technique [0002] According to the nature of the reaction, the traditional methods can be divided into physical preparation and chemical preparation. Among them, the physical method is to micronize large-grained substances by physical means to obtain nanoparticles, mainly including high-energy ball milling, physical vapor deposition and deep plastic deformation. Generally speaking, the shape of particles prepared by physical methods is uncontrollable; Chemical methods to obtain nanoparticles from smaller atoms or molecules mainly include chemical vapor deposition, sol-gel method, chemical liquid phase reduction method, thermal decomposition of carbonyl iron method and co-precipitation method. Whereas in chemical methods, Fe(II) or ...

AI Technical Summary

Problems solved by technology

The pollution of chromium to the environment cannot be underestimated, and it has seriously threatened the normal ecology and human health. As early as 2005, my country issued the "Comprehensive Treatment Plan for Chromium Slag Pollution", requiring all historical chromium residues to be removed before 2010. Harmless disposal and invested a lot of money for this, but the final result is regrettable, only 7 of the 19 provinces that require rectification in the policy have completely disposed of the chromium slag[6]

The original national pledge failed to achieve the desired results due to the lack of follow-up regulation

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