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

Yanfang Liu; Wei Gao; Rui Liu; Wenjing Zhang; Jianrui Niu; Xiaoyue Lou; Gong Li; Haoyun Liu; Zaixing Li

doi:10.1002/wer.10763

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

Water Environ Res. 2022 Jul;94(7):e10763. doi: 10.1002/wer.10763.

Authors

Yanfang Liu^{1

2}, Wei Gao^{2

3}, Rui Liu^{2

3}, Wenjing Zhang^{1

2}, Jianrui Niu^{1

2}, Xiaoyue Lou⁴, Gong Li⁴, Haoyun Liu⁴, Zaixing Li^{1

2}

Affiliations

¹ School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, China.
² Pollution Prevention Biotechnology Laboratory of Hebei Province, Shijiazhuang, China.
³ School of Civil Engineering, Hebei University of Science and Technology, Shijiazhuang, China.
⁴ Tianjin Redsun Water Industry Company Limited, Tianjin, China.

PMID: 35822693
DOI: 10.1002/wer.10763

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 CO₃ ^2- , 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.

Keywords: Fenton sludge; biochar; mechanism; performance; phosphorus adsorption.

MeSH terms

Charcoal
Phosphorus*
Powders
Sewage* / chemistry
Sodium Hydroxide

Substances

Powders
Sewage
biochar
Charcoal
Phosphorus
Sodium Hydroxide

Abstract

MeSH terms

Substances

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