Research Progress on Adsorption and Removal of Food Contaminants by MOF-based Materials

Food safety is vitally important for human health. Food contaminants are liable to be introduced into food products during the processes of production, transportation and storage, such as heavy metal ions, organic pesticides, dyes, pharmaceuticals and personal care products (PPCPs), and mycotoxin and persistent organic pollutants (POPs). The removal of these pollutants from contaminated food is of great significance to the food industry. Compared with traditional processing approaches such as electro/photocatalytic degradation, chemical oxidation, extraction, enzymatic degradation and microbial degradation, the removal of food contaminants by adsorption has the advantages of high efficiency, low energy consumption and flexible operation. It is one of the most prospective methods to remove food contaminants. Metal-organic frameworks (MOFs) are a new kind of porous material with the characteristics of large specific surface area, high porosity and modifiable pores. A large number of researches have shown that stable MOF materials are suitable for the removal of food contaminants as an ideal platform.Additionally, the adsorption performance of MOF materials can be improved by rational design, post-modification and morphology regulation. The recent progress in the removal of various food contaminants by MOF-based adsorbents was summarized. Particularly, the adsorption mechanisms of MOF-based adsorbents for food contaminants, including electrostatic effect, acid-base/coordination effect, π-π accumulation effect, hydrogen bond effect and synergy, were systematically analyzed. The promising tendencies and confronting challenges in the field were concluded and it will provide theoretical and practice basis for MOF-based adsorbents for food contaminants.