Application of hybrid photocatalysis systems coupled with flocculation and adsorption to biologically treated sewage effluent for organic removal

Abstract

The application of a photocatalysis hybrid system coupled with flocculation and adsorption in treating biologically treated sewage effluent (BTSE) was investigated. The removal of organic matter was studied in terms of dissolved organic matter (DOC), removal of hydrophobic (HP), transphilic (TP) and hydrophilic (HL) fractions, and molecular weight (MW) distribution. The photooxidation removed the majority of MW (263, 580, 865, and 43109 daltons) within the first 30 minutes of operation. The removal of MW range of organic matter of 330 daltons was low. DOC removal of HP and TP was high (80%). DOC removal from HL fraction was, however, minimum. The photocatalytic system with simultaneous PAC adsorption and FeCl3 flocculation removed the effluent organic matter (EfOM) up to 90%. Therefore, photocatalysis with the ferric chloride (FeCl3) flocculation and PAC adsorption hybrid system can be a possible option in the removal of DOC from BTSE for water reuse.