Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture
In order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diff...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2024-01-01
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| Series: | Materials Research Express |
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| Online Access: | https://doi.org/10.1088/2053-1591/ad239d |
| _version_ | 1797321501208215552 |
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| author | Mingjun Zhang Liang Li Fan Yang Shigang Zhang He Zhang Jian An |
| author_facet | Mingjun Zhang Liang Li Fan Yang Shigang Zhang He Zhang Jian An |
| author_sort | Mingjun Zhang |
| collection | DOAJ |
| description | In order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diffraction (XRD), differential thermal Analysis (DTA), thermogravimetry (TG), infrared analysis (IR) and scanning electron microscope (SEM). The mechanical properties of cement mortar with 30% coal gangue auxiliary cementitious admixture were also measured to determine the optimal calcining temperature. As calcining temperature was increased, the coal gangue experienced the following transformations: carbon combustion, dehydroxylation, metakaolin transformation and mullite transformation. The cement mortar with coal gangue auxiliary cementitious admixture calcined at 700 °C presented the highest 28-d flexural and compressive strength, increasing by 8.27% and 11.85% respectively as compared with the benchmark cement mortar. The maximum dosage of coal gangue auxiliary cementitious admixture in cement mortar was further identified to be less than 30% by mechanical properties testing. The activity of high alumina coal gangues at different calcining temperatures was explained from the view points of hydration degree and products. The present investigation can provide a useful reference to utilize high alumina coal gangue as auxiliary cementitious admixture by means of a simple thermal activation at 700 °C. |
| first_indexed | 2024-03-08T04:59:25Z |
| format | Article |
| id | doaj.art-73db395a34d8460a9b6eef43e8bfa28a |
| institution | Directory Open Access Journal |
| issn | 2053-1591 |
| language | English |
| last_indexed | 2024-03-08T04:59:25Z |
| publishDate | 2024-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Materials Research Express |
| spelling | doaj.art-73db395a34d8460a9b6eef43e8bfa28a2024-02-07T13:09:17ZengIOP PublishingMaterials Research Express2053-15912024-01-0111202520110.1088/2053-1591/ad239dThermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixtureMingjun Zhang0Liang Li1Fan Yang2Shigang Zhang3He Zhang4Jian An5https://orcid.org/0000-0003-0807-7478Department of Materials Science and Engineering, Jilin University , Changchun 130025, People’s Republic of ChinaJinneng Holding Coal Industry Group, Co., Ltd, Datong, 037000, People’s Republic of ChinaJinneng Holding Coal Industry Group, Co., Ltd, Datong, 037000, People’s Republic of ChinaDepartment of Materials Science and Engineering, Jilin University , Changchun 130025, People’s Republic of ChinaDepartment of Materials Science and Engineering, Jilin University , Changchun 130025, People’s Republic of ChinaDepartment of Materials Science and Engineering, Jilin University , Changchun 130025, People’s Republic of ChinaIn order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diffraction (XRD), differential thermal Analysis (DTA), thermogravimetry (TG), infrared analysis (IR) and scanning electron microscope (SEM). The mechanical properties of cement mortar with 30% coal gangue auxiliary cementitious admixture were also measured to determine the optimal calcining temperature. As calcining temperature was increased, the coal gangue experienced the following transformations: carbon combustion, dehydroxylation, metakaolin transformation and mullite transformation. The cement mortar with coal gangue auxiliary cementitious admixture calcined at 700 °C presented the highest 28-d flexural and compressive strength, increasing by 8.27% and 11.85% respectively as compared with the benchmark cement mortar. The maximum dosage of coal gangue auxiliary cementitious admixture in cement mortar was further identified to be less than 30% by mechanical properties testing. The activity of high alumina coal gangues at different calcining temperatures was explained from the view points of hydration degree and products. The present investigation can provide a useful reference to utilize high alumina coal gangue as auxiliary cementitious admixture by means of a simple thermal activation at 700 °C.https://doi.org/10.1088/2053-1591/ad239dhigh alumina coal ganguekaolinitethermal activationmechanical propertiesmicrostructurecementitious admixture |
| spellingShingle | Mingjun Zhang Liang Li Fan Yang Shigang Zhang He Zhang Jian An Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture Materials Research Express high alumina coal gangue kaolinite thermal activation mechanical properties microstructure cementitious admixture |
| title | Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| title_full | Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| title_fullStr | Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| title_full_unstemmed | Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| title_short | Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| title_sort | thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture |
| topic | high alumina coal gangue kaolinite thermal activation mechanical properties microstructure cementitious admixture |
| url | https://doi.org/10.1088/2053-1591/ad239d |
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