Treatment of soy sauce wastewater with biomimetic dynamic membrane for colority removal and chemical oxygen demand lowering

Abstract

Soy sauce wastewater has been produced in soy sauce production and consumption. To reuse this kind of water resource, the chemical oxygen demand (COD), colority should be removed or lowered. Biomimetic dynamic membrane (BDM), GO&Laccase@UF membrane, was prepared by filtering mixture of graphene oxide (GO) and laccase through ultrafiltration (UF) membrane. Compared to UF membrane, the prepared BDM showed great performance in removal of COD and colority, due to the higher laccase activity with existence of GO. The removal rate of colority reached ~80% by one step filtration operation. Moreover, the multiple cycle test evidenced that the value of COD and colority in the permeate after 5 consecutive cycles with the same GO&Laccase@UF membrane still meet the standard for reuse water. This work indicates the promising of BDM for wastewater from food industry.

Key words
Soy sauce waste; biomimetic dynamic membrane; filtration; colority removal