Characterizing groundwater turbidity reduction by using a magnetic biocarbon adsorbent composite (MBAC): Process optimization

Abstract

The use of groundwater as drinking water source in many parts of Kelantan encourages the research and development of various cost-effective alternative adsorbent material for turbidity reduction and drinking water purification. The preparation, characterization, and use of a magnetic biocarbon adsorbent composite (MBAC) is introduced in this study as an option to treat turbid groundwater. In contrast to commercial activated carbon (CAC), peak shifts and peaks denoting Fe-O bending were observed in the FTIR spectrum of MBAC. The adsorption process for turbidity reduction by MBAC and CAC was investigated. A factorial design matrix consisting of four parameters were tabulated, namely, adsorbent dosage (0.02, 0.04, and 0.06 g), agitation time (15, 30, and 60 min), agitation rate (150, 200, and 250 rpm), and two adsorbent particle size ranges (M: 300 < x ≤ 500 μm, and Q: ≤ 45 μm). The predictive model was validated with 0.04 g MBAC of ≤ 45 μm in particle size, agitated at 150 rpm, for 48 min, that attained 98.46% turbidity removal efficiency with a final NTU reading of 0.40. Conversely, CAC removed 88.19% for a final NTU reading of 3.07. Overall, the iron oxide impregnated biocarbon composite showed better turbidity reduction capability compared to CAC. The findings of this work support the potential application of MBAC as an alternative adsorbent for the treatment of groundwater sourced drinking water.