Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar

The disposal of sludge and the treatment of phosphorus in water bodies are significant environmental challenges. This study explores the adsorption performance and mechanism of lanthanum-calcium modified sludge/wheat straw biochar (LC-SWBC). LC-SWBC was prepared through a one-step hydrothermal carbo...

Full description

Saved in:
Bibliographic Details
Main Authors: Weijin Gong, Chenhan Tao, Zhenbang Tian, Zuohua Huang, Hongtao Lin, Chaozhi Qi, Zhengyang Yu, Lina Guo
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-06-01
Series:Frontiers in Environmental Science
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fenvs.2025.1604542/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850160800949338112
author Weijin Gong
Chenhan Tao
Zhenbang Tian
Zuohua Huang
Hongtao Lin
Chaozhi Qi
Zhengyang Yu
Lina Guo
author_facet Weijin Gong
Chenhan Tao
Zhenbang Tian
Zuohua Huang
Hongtao Lin
Chaozhi Qi
Zhengyang Yu
Lina Guo
author_sort Weijin Gong
collection DOAJ
description The disposal of sludge and the treatment of phosphorus in water bodies are significant environmental challenges. This study explores the adsorption performance and mechanism of lanthanum-calcium modified sludge/wheat straw biochar (LC-SWBC). LC-SWBC was prepared through a one-step hydrothermal carbonization process and was used to remove phosphorus from water. The results indicate that La(OH)3 and Ca(OH)2 were successfully loaded onto the surface of the biochar. The adsorption of phosphates by LC-SWBC follows a pseudo-second-order kinetic model and the Langmuir model, with a maximum theoretical adsorption capacity of 80.78 mg P/g. LC-SWBC exhibits selective adsorption of phosphate under competitive anion experiments. In actual wastewater treatment, LC-SWBC can effectively remove phosphates, achieving a total phosphorus concentration of 0.77 mg/L at a dosage of 0.4 g/L, meet the discharge standard of class I B pollutants (1 mg/L) in GB 18918-2002 of China. In addition, the hydrothermal liquid of LC-SWBC is primarily composed of organic phosphorus (OP); after adsorption, the main component in the biochar LC-SWBC-P is apatite phosphate (AP), both of which provide biochemical utilization conditions for phosphorus resource recovery and recycling.
format Article
id doaj-art-4b04cb57fcf043d28d5cdc2365a8fc68
institution OA Journals
issn 2296-665X
language English
publishDate 2025-06-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Environmental Science
spelling doaj-art-4b04cb57fcf043d28d5cdc2365a8fc682025-08-20T02:23:04ZengFrontiers Media S.A.Frontiers in Environmental Science2296-665X2025-06-011310.3389/fenvs.2025.16045421604542Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biocharWeijin Gong0Chenhan Tao1Zhenbang Tian2Zuohua Huang3Hongtao Lin4Chaozhi Qi5Zhengyang Yu6Lina Guo7School of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaSchool of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaInstitute of Chemistry Co., Ltd. Henan Academy of Sciences, Zhengzhou, ChinaInstitute of Chemistry Co., Ltd. Henan Academy of Sciences, Zhengzhou, ChinaSchool of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaSchool of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaSchool of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaSchool of Energy and Environment, Zhongyuan University of Technology, Zhengzhou, ChinaThe disposal of sludge and the treatment of phosphorus in water bodies are significant environmental challenges. This study explores the adsorption performance and mechanism of lanthanum-calcium modified sludge/wheat straw biochar (LC-SWBC). LC-SWBC was prepared through a one-step hydrothermal carbonization process and was used to remove phosphorus from water. The results indicate that La(OH)3 and Ca(OH)2 were successfully loaded onto the surface of the biochar. The adsorption of phosphates by LC-SWBC follows a pseudo-second-order kinetic model and the Langmuir model, with a maximum theoretical adsorption capacity of 80.78 mg P/g. LC-SWBC exhibits selective adsorption of phosphate under competitive anion experiments. In actual wastewater treatment, LC-SWBC can effectively remove phosphates, achieving a total phosphorus concentration of 0.77 mg/L at a dosage of 0.4 g/L, meet the discharge standard of class I B pollutants (1 mg/L) in GB 18918-2002 of China. In addition, the hydrothermal liquid of LC-SWBC is primarily composed of organic phosphorus (OP); after adsorption, the main component in the biochar LC-SWBC-P is apatite phosphate (AP), both of which provide biochemical utilization conditions for phosphorus resource recovery and recycling.https://www.frontiersin.org/articles/10.3389/fenvs.2025.1604542/fullhydrothermal carbonizationsewage sludgephosphorus adsorptionbiocharwheat straw
spellingShingle Weijin Gong
Chenhan Tao
Zhenbang Tian
Zuohua Huang
Hongtao Lin
Chaozhi Qi
Zhengyang Yu
Lina Guo
Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
Frontiers in Environmental Science
hydrothermal carbonization
sewage sludge
phosphorus adsorption
biochar
wheat straw
title Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
title_full Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
title_fullStr Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
title_full_unstemmed Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
title_short Characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge/wheat straw biochar
title_sort characterization and mechanism of phosphorus adsorption from wastewater by lanthanum calcium doped sludge wheat straw biochar
topic hydrothermal carbonization
sewage sludge
phosphorus adsorption
biochar
wheat straw
url https://www.frontiersin.org/articles/10.3389/fenvs.2025.1604542/full
work_keys_str_mv AT weijingong characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT chenhantao characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT zhenbangtian characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT zuohuahuang characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT hongtaolin characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT chaozhiqi characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT zhengyangyu characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar
AT linaguo characterizationandmechanismofphosphorusadsorptionfromwastewaterbylanthanumcalciumdopedsludgewheatstrawbiochar