Removal of phosphorus using biochar derived from Fenton sludge: Mechanism and performance insights

Abstract

A phosphorus removal biochar adsorbent was prepared from Fenton sludge. The adsorption process was optimized, and its phosphorus adsorption mechanism was discussed. It was found that the phosphorus adsorption performance of biochar prepared from single Fenton sludge (FBC‐400) was better than that of co‐pyrolysis of Fenton sludge and bamboo powder. The optimum condition was that Fenton sludge pyrolyzed at 400°C (FBC‐400). FBC‐400 had a larger specific surface area than that prepared by co‐pyrolysis with bamboo powder. And the high content of iron element could provide a higher surface charge of the biochar, thereby increasing the electrostatic adsorption of phosphorus onto FBC‐400. The phosphorus adsorption was highly pH dependent by FBC‐400, which can enhance electrostatic adsorption and increase adsorption capacity in acidic conditions. The effect of coexisting anion on adsorption performance was mainly affected by CO32−, reducing the adsorption capacity by at least 49%, whereas other anions had no obvious interference. The adsorption process of FBC‐400 accorded with the pseudo‐second‐order kinetic model and the Langmuir model, which indicated that the adsorption process was monolayer adsorption and mainly chemical adsorption, and the maximum saturated phosphorus adsorption capacity was 8.77 mg g−1. The mechanisms for phosphorus adsorption were electrostatic adsorption and inner‐sphere complexing. 1 M NaOH was used for desorption, and the adsorption capacity remained at 81% in the fifth cycle. Practitioner Points The Fenton sludge biochar usage as an adsorbent could be a win‐win strategy to convert waste biomass to valuable ‐ product. The adsorption process accorded with the Langmuir model, the maximum phosphorus adsorption capacity was 8.77 mg/g at 25°C. The adsorption mechanisms were electrostatic adsorption and inner‐sphere complexing. 1M NaOH was used for desorption, and the adsorption capacity remained at 81% in the fifth cycle.

Bimetallic nanoparticles and biochar produced by Adansonia Digitata shell and their effect against tomato pathogenic fungi

“…10C . Recent studies have shown that biochar prepared from Fenton sludge has a rough surface and an irregular flaky structure ( Liu et al, 2022 ). On the other hand, biochar derived from rubberwood sawdust had a cylindrical shape ( Ali et al, 2022 ).…”

Screening of Raw and Modified Biochars from Food Processing Wastes for the Removal of Phosphates, Nitrates, and Ammonia from Water

“…The modification of the coffee biochar with magnesium resulted in increase in the sorption capacity at both pyrolysis temperatures. The increase in the p rolysis temperature improved phosphate sorption only in the case of modified biocha The effect of the pyrolysis temperature (from 300 to 600 °C) for the production of bioch from the co-pyrolysis of fenton sludge and bamboo was also examined [46]. The max mum phosphorus sorption capacity was observed at 400 °C for the fenton sludge and w 8.77 mg/g.…”

Feasibility of electrodeionization for phosphate removal

“…Phosphate can be eliminated from water samples by various techniques, including adsorption, biosorption, biological processes, ion exchange, chemical precipitation, coagulation/flotation, and membrane processes. Numerous researchers in the past years have reviewed the advantages, limitations, and applications of some of these methods (Almanassra et al, 2021; Huang et al, 2017; Liu et al, 2022; Recepoglu et al, 2022; van Loosdrecht et al, 1997; Zheng et al, 2022).…”