PVA entrapped activated sludge beads coated with PAC for bioremediating 4-chlorophenol-bearing wastewater
This study compared the effectiveness of powdered activated carbon (PAC) to adsorb 4-chlorophenol (4-CP) from wastewater via coated onto and homogenised into polyvinyl alcohol (PVA) bead surface. The bioregeneration of spent PAC for repeated uses via entrapment with 4-CP acclimated biomass of activated sludge was also unveiled. Results showed that the maximum capacity of PAC adsorbing 4-CP was 0.2 g 4-CP/g PAC. It was confirmed that the PAC coated onto bead surfaces with biomass entrapment could be used for 8 cycles with removal efficiency ranging from 80-85%. The removal rate of 4-CP was best fitted by the pseudo-first-order reaction kinetic, permitting plausibly projection to upscale for industrial application in treating wastewater containing chlorophenol more effectively.
Keywords— Activated sludge; adsorption; bioregeneration; PAC coated beads; biomass entrapment; 4-chlorophenol
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