Zero-valent iron-mineral composite material with high reduction activity and preparation method therefor

Abstract

The invention relates to a zero-valent iron-mineral composite material with high reduction activity. The zero-valent iron-mineral composite material is obtained through subjecting elemental iron and an inorganic nonmetallic mineral, which are in a mass ratio of (4 to 10): 10, to ball milling in a planetary ball milling tank, wherein specific ball milling process conditions are as follows: the ratio of grinding media to material is 30 to 45, the ball milling time is 7 to 8 hours, and the revolution rate of ball milling is 500rpm to 600rpm. According to the zero-valent iron-mineral composite material with high reduction activity and the preparation method therefor, the inorganic nonmetallic mineral material and the elemental iron are combined, a specific ball milling process is employed, andthus, the inorganic nonmetallic mineral can form a dense amorphous-structured oolitic protective layer on the surface of zero-valent iron, so that on one hand, the sustained reduction power of the zero-valent iron is improved, in addition, the reactivity of the ball-milling-activated inorganic nonmetallic mineral is higher, and the zero-valent iron in the composite material is exposed.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and in particular relates to a highly reducing active zero-valent iron-mineral composite material and a preparation method thereof. Background technique [0002] With the improvement of people's requirements for living environment and ecological civilization, water pollution has attracted more and more attention. Water pollution mainly comes from domestic sewage, industrial wastewater and initial rainwater. The composition of actual wastewater is complex, containing a large amount of organic and inorganic Pollutants pose a huge threat to ecology and human health. [0003] The reduction precipitation method is a major chemical method in the process of water pollution control. It degrades or reduces oxidative pollutants on the basis of adding a reducing agent, and removes them in the form of precipitation. Zero-valent iron (ZVI) is a typical the reducing agent. It refers to iron element p...

AI Technical Summary

Problems solved by technology

However, the surface of highly active zero-valent iron is easily passivated, and the fine-grained zero-valent iron itself is easy to agglomerate. These defects in the nature of zero-valent iron affect its reactivity and limit the further application of zero-valent iron.

Researchers have done a lot of research on the preparation and modification of zero-valent iron, improved the preparation process, and used different types of inorganic non-metallic materials to load zero-valent iron, such as graphene, bentonite, chitosan and other clays, etc. , the process is basically prepared by liquid phase precipitation in a vacuum environment. Although products with smaller particle sizes can be obtained, the high cost of using sodium borohydride and other reducing agents and inert protective gases has become an obstacle. In addition, the preparation The process also removes large volumes of waste water that require further treatment

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