Phosphorus removal from domestic sewage by adsorption combined photocatalytic reduction with red mud

Abstract

A B S T R A C TPhosphorus removal from domestic sewage by adsorption combined photocatalytic reduction with raw and modified red mud (RM) was studied in this paper. The results indicated that RM dosage, reaction time, stirring rate, phosphorus concentration, and initial pH of solution (pH i ) were the main factors to effect on phosphorus removal. It was found that the phosphorus removal efficiency of modified red mud (RM-m) under the photocatalytic test conditions was higher than only by adsorption process, while raw red mud (RM-raw) showed no significant difference under the two conditions. With initial phosphorus concentration 8.26 mg/L, reaction time 60 min, stirring rate 200 r/min, under the adsorption and photocatalytic test conditions, the optimum dosage and pH i of both RM-raw and RM-m were 1.8 g/L and 4.0, respectively, and the corresponding phosphorus removal of RM-raw and RM-m were 90.18 and 91.70%, respectively. The optimum amount of RM-m under the two conditions were 1.6 and 1.5 g/L, respectively, the optimal pH i 3.0, correspondingly, the phosphorus removal could reach high up to 94.30 and 99.96%, respectively.

A novel peat-based biosorbent for the removal of phosphate from synthetic and real wastewater and possible utilization of spent sorbent in land application

“…Although the sorption capacity of raw peat is low, we presume that it can be significantly increased by modifying peat with iron compounds. Naturally occurring iron-rich materials and waste products, such as low-grade iron ore [8], steel slags [9], red mud [10], ferric sludge [2], ferric water treatment residuals [11], iron oxides [12], iron-rich humus soils [13], iron oxide tailings [1], ironrich calcareous soils [14], and goethite [15], are known for high affinities for phosphate sorption, and most of them have been tested as adsorbents in laboratoryscale experiments to remove phosphorus compounds.…”