Multi-faceted strategy based on enzyme immobilization with reactant adsorption and membrane technology for biocatalytic removal of pollutants: A critical review

In the modern era, the use of sustainable, environmentally friendly alternatives for removal of recalcitrant pollutants in streams resulting from industrial processes is of key importance. In this context, biodegradation of phenolic compounds, pharmaceuticals and dyes in wastewater by using oxidoreductases offers numerous benefits. Tremendous research efforts have been made to develop novel, hybrid strategies for simultaneous immobilization of oxidoreductase and removal of toxic compounds. The use of support materials with the options for combining enzyme immobilization with adsorption technology focused on phenolic pollutants and products of biocatalytic conversion seems to be of particular interest. Application of enzymatic reactors based on immobilized oxidoreductases for coupling enzyme-aided degradation and membrane separation also attract still growing attention. However, prior selection of the most suitable support/sorbent material and/or membrane as well as operational mode and immobilization technique is required in order to achieve high removal efficiency. Thus, in the framework of this review, we present an overview of the impact of support/sorbent material on the catalytic properties of immobilized enzymes and sorption of pollutants as well as parameters of membranes for effective bioconversion and separation. Finally, future perspectives of the use of processes combining enzyme immobilization and sorption technology as well as application of enzymatic reactors for removal of environmental pollutants are discussed.