Nano-rod Ca-decorated sludge derived carbon for removal of phosphorus
Lingjun Kong1, Meina Han2, Kaimin Shih3
1School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Radioactive Contamination Control and Resources, Guangzhou 5100056, PR China; Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China.
Abstract:
Recovering phosphorus (P) from waste streams takes the unique advantage in simultaneously addressing the crisis of eutrophication and the shortage of P resource. A novel calcium decorated sludge carbon (Ca-SC) was developed from dyeing industry wastewater treatment sludge by decorating calcium (Ca) to effectively adsorb phosphorus from solution. The X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques were used to characterize the Ca-SCs, followed by isotherm and kinetic sorption experiments. A preferred design with CaCO3 to sludge mass ratio of 1:2 was found to have a sorption capacity of 116.82 mg/g for phosphorus. This work reveals the crucial role of well-dispersed nano-rod calcium on the Ca-SC surface for the sorption of phosphorus. Moreover, the decoration of nano-rod calcium was found to further promote the uptake of phosphorus through the formation of hydroxylapatite (Ca5(PO4)3(OH)). Thus, the development of decorated Ca-SC for sorption of phosphorus is very important in solving the P pollution and resource loss.
