Synthesis and application of polyacrylamide grafted magnetic cellulose flocculant for palm oil wastewater treatment

Abstract

Accumulation of organic load in palm oil mill wastewater has become a major issue of concern. In this study, a new polyacrylamide grafted onto magnetic cellulose (PAM-g-MagCell) was successfully produced by microwave assisted synthesis and used as flocculant for the removal of total suspended solid (TSS), turbidity, chemical oxygen demand (COD) and colour. The physical and chemical properties of the PAM-g-MagCell were characterized by Fourier transform infrared spectroscopy, vibrating sample magnetometer, zeta potential and elemental analysis. A jar test method was employed to perform flocculation, which was evaluated on anaerobically treated palm oil mill effluent suspension. The flocculants dosage, initial pH and settling time were varied to study the effects of these variables on contaminant removal from wastewater. The best conditions for the removal of TSS, turbidity, COD, and colour were achieved at flocculants dosage of 1.5 »g/L, pH of 8.0 and settling time of 30 »min. Under these conditions, the removal of TSS, turbidity, COD, and colour were 82.97 %, 88.62 %, 53.23 % and 91.76 %, respectively. The PAM-g-MagCell also showed better performance when compared with cellulose, magnetic cellulose (MagCell), polyacrylamide, and alum. In conclusion, all the results show that the PAM-g-MagCell as alternative flocculant has great application prospects in the removal of organic matters from palm oil mill wastewater.