Comparison between the coagulants surfactant modified bentonite, combination chitosan-natural bentonite and combination chitosan-modified bentonite for peat water treatment

Abstract

Peat water is an abundant water resource in Asia, especially in rural areas. However, it is unsuitable to be used as a commercial water supply. Monitoring peat water characteristics at Beriah swamp, Perak, recorded colour (238 PtCo), turbidity (12.86 NTU), iron (0.89 mg/L), pH (4.8) and chemical oxygen demand (COD) (27 mg/L) over the national limitation standards. In this study, surfactant modified bentonite (SMB) shows high removal of colour (95%), turbidity (97%) and iron (100%) from peat water, but not COD (almost non-removal). From the results obtained, treatment of peat water using a combination of chitosan-natural bentonite was more efficient by the resulting optimal removal for all parameters such as colour (78%), turbidity (89%), iron (90%) and COD (67%). Meanwhile, a combination of chitosan-SMB gave similar results as SMB alone; however, reducing the amount of pollutants used in combination was advantageous in this combination. The response surface method was applied and the optimal reaction between coagulant and sample due to pH, dosage and contact time was determined.