Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits
This study aims to enhance the sustainable utilization of electrolytic manganese residue (EMR), an industrial solid waste rich in sulfates and pollutants, by modifying it with appropriate proportions of granulated blast furnace slag (GBFS) and carbide slag (CS) and evaluating its potential as a ceme...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-05-01
|
| Series: | Buildings |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-5309/15/10/1586 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849711467358584832 |
|---|---|
| author | Liang Tang Jan Fořt Robert Černý Zhaoyi He |
| author_facet | Liang Tang Jan Fořt Robert Černý Zhaoyi He |
| author_sort | Liang Tang |
| collection | DOAJ |
| description | This study aims to enhance the sustainable utilization of electrolytic manganese residue (EMR), an industrial solid waste rich in sulfates and pollutants, by modifying it with appropriate proportions of granulated blast furnace slag (GBFS) and carbide slag (CS) and evaluating its potential as a cement retarder. The influence of both the GBFS/CS ratio and the dosage of modified EMR on the performance of cement mortar was systematically investigated, focusing on workability, mechanical properties, hydration behavior, leaching toxicity, and carbon emissions. Results showed that GBFS and CS significantly reduced pollutant concentrations in EMR while improving gypsum crystallinity. Modified EMR exhibited retarding properties, extending the initial and final setting times of cement mortar from 98 min and 226 min to 169 min and 298 min. With an 8 wt.% dosage, the 28-day compressive strength reached 58.76 MPa, a 1.3-fold increase compared to cement mortar (45.21 MPa). The content of reactive SiO<sub>2</sub>, Al<sub>2</sub>O<sub>3</sub>, Ca(OH)<sub>2</sub>, and CaSO<sub>4</sub>·2H<sub>2</sub>O promoted secondary hydration of cement and generated significant ettringite (AFt) and calcium silicate hydrate (C-S-H) gels, forming a dense microstructure. Pollutants in the modified EMR-cement mortar were reduced through precipitation, substitution, and encapsulation, meeting leaching toxicity standards. This study highlights the feasibility and environmental benefits of employing modified EMR as a cement retarder, demonstrating its potential in sustainable building materials. |
| format | Article |
| id | doaj-art-2c6b2409d8564de9af0f7205d5601bfe |
| institution | DOAJ |
| issn | 2075-5309 |
| language | English |
| publishDate | 2025-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Buildings |
| spelling | doaj-art-2c6b2409d8564de9af0f7205d5601bfe2025-08-20T03:14:36ZengMDPI AGBuildings2075-53092025-05-011510158610.3390/buildings15101586Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental BenefitsLiang Tang0Jan Fořt1Robert Černý2Zhaoyi He3School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, ChinaDepartment of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 16629 Prague, Czech RepublicDepartment of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 16629 Prague, Czech RepublicSchool of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, ChinaThis study aims to enhance the sustainable utilization of electrolytic manganese residue (EMR), an industrial solid waste rich in sulfates and pollutants, by modifying it with appropriate proportions of granulated blast furnace slag (GBFS) and carbide slag (CS) and evaluating its potential as a cement retarder. The influence of both the GBFS/CS ratio and the dosage of modified EMR on the performance of cement mortar was systematically investigated, focusing on workability, mechanical properties, hydration behavior, leaching toxicity, and carbon emissions. Results showed that GBFS and CS significantly reduced pollutant concentrations in EMR while improving gypsum crystallinity. Modified EMR exhibited retarding properties, extending the initial and final setting times of cement mortar from 98 min and 226 min to 169 min and 298 min. With an 8 wt.% dosage, the 28-day compressive strength reached 58.76 MPa, a 1.3-fold increase compared to cement mortar (45.21 MPa). The content of reactive SiO<sub>2</sub>, Al<sub>2</sub>O<sub>3</sub>, Ca(OH)<sub>2</sub>, and CaSO<sub>4</sub>·2H<sub>2</sub>O promoted secondary hydration of cement and generated significant ettringite (AFt) and calcium silicate hydrate (C-S-H) gels, forming a dense microstructure. Pollutants in the modified EMR-cement mortar were reduced through precipitation, substitution, and encapsulation, meeting leaching toxicity standards. This study highlights the feasibility and environmental benefits of employing modified EMR as a cement retarder, demonstrating its potential in sustainable building materials.https://www.mdpi.com/2075-5309/15/10/1586electrolytic manganese residuecement retarderworkabilityhydration mechanismCO<sub>2</sub> emissions |
| spellingShingle | Liang Tang Jan Fořt Robert Černý Zhaoyi He Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits Buildings electrolytic manganese residue cement retarder workability hydration mechanism CO<sub>2</sub> emissions |
| title | Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits |
| title_full | Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits |
| title_fullStr | Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits |
| title_full_unstemmed | Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits |
| title_short | Sustainable Utilization of Modified Electrolytic Manganese Residue as a Cement Retarder: Workability, Mechanical Properties, Hydration Mechanisms, Leaching Toxicity, and Environmental Benefits |
| title_sort | sustainable utilization of modified electrolytic manganese residue as a cement retarder workability mechanical properties hydration mechanisms leaching toxicity and environmental benefits |
| topic | electrolytic manganese residue cement retarder workability hydration mechanism CO<sub>2</sub> emissions |
| url | https://www.mdpi.com/2075-5309/15/10/1586 |
| work_keys_str_mv | AT liangtang sustainableutilizationofmodifiedelectrolyticmanganeseresidueasacementretarderworkabilitymechanicalpropertieshydrationmechanismsleachingtoxicityandenvironmentalbenefits AT janfort sustainableutilizationofmodifiedelectrolyticmanganeseresidueasacementretarderworkabilitymechanicalpropertieshydrationmechanismsleachingtoxicityandenvironmentalbenefits AT robertcerny sustainableutilizationofmodifiedelectrolyticmanganeseresidueasacementretarderworkabilitymechanicalpropertieshydrationmechanismsleachingtoxicityandenvironmentalbenefits AT zhaoyihe sustainableutilizationofmodifiedelectrolyticmanganeseresidueasacementretarderworkabilitymechanicalpropertieshydrationmechanismsleachingtoxicityandenvironmentalbenefits |