Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3
Granulated copper slag (GCS) is currently applied to partial cement replacement as a supplementary cementitious material (SCM), but with a low rate due to its low pozzlanic activity. In this contribution we introduce an approach to enhance the reactivity of GCS by modifying the mineral structure usi...
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| Format: | Article |
| Language: | English |
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Elsevier
2022-05-01
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| Series: | Journal of Materials Research and Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785422003143 |
| _version_ | 1818321124105125888 |
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| author | Qinli Zhang Bingyi Zhang Yan Feng Chongchong Qi Qiusong Chen Chongchun Xiao |
| author_facet | Qinli Zhang Bingyi Zhang Yan Feng Chongchong Qi Qiusong Chen Chongchun Xiao |
| author_sort | Qinli Zhang |
| collection | DOAJ |
| description | Granulated copper slag (GCS) is currently applied to partial cement replacement as a supplementary cementitious material (SCM), but with a low rate due to its low pozzlanic activity. In this contribution we introduce an approach to enhance the reactivity of GCS by modifying the mineral structure using calcium oxide (CaO) and aluminum oxide (Al2O3) both by 10 wt.%, in a molten state. Blended cement pastes were formulated using cement (70 wt.%) and the modified GCS (30 wt.%). The development of hydration heat and strength were examined using isothermal calorimetry and strength tests, respectively. The mineral composition and microstructure of hydration products for different reaction periods were examined using X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). Also, toxicity characteristic leaching procedure (TCLP) was performed on the samples. Results showed an increase in the hydration heat emission rate from the early hydration and the compressive strength of blended cement paste after curing for 28 days, indicating that the addition of CaO and Al2O3 in GCS improves pozzolanic activity. XRD and SEM-EDS analysis indicated that the modified GCS consumed more calcium hydroxide (CH) accompanied by increased generation of calcium silicate hydrate (C–S–H) gels in blended cement with a microstructure containing more gel phases and fewer pores, forming a more compact structure. Leaching of heavy metals of paste samples was lower than Environmental Protection Agency (EPA) limit. It is possible to apply the modified GCS as a sustainable material to promote cleaner production for cement and concrete industries. |
| first_indexed | 2024-12-13T10:35:55Z |
| format | Article |
| id | doaj.art-4ec681c7b27447e39aae885191a0c331 |
| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-12-13T10:35:55Z |
| publishDate | 2022-05-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj.art-4ec681c7b27447e39aae885191a0c3312022-12-21T23:50:43ZengElsevierJournal of Materials Research and Technology2238-78542022-05-0118909920Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3Qinli Zhang0Bingyi Zhang1Yan Feng2Chongchong Qi3Qiusong Chen4Chongchun Xiao5School of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, ChinaSchool of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, ChinaSchool of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, China; Corresponding author.School of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, ChinaSchool of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, ChinaSchool of Resources and Safety Engineering, Central South University, Changsha, 410083, Hunan Province, China; Feny Co., Ltd., Changsha, 410083, Hunan Province, ChinaGranulated copper slag (GCS) is currently applied to partial cement replacement as a supplementary cementitious material (SCM), but with a low rate due to its low pozzlanic activity. In this contribution we introduce an approach to enhance the reactivity of GCS by modifying the mineral structure using calcium oxide (CaO) and aluminum oxide (Al2O3) both by 10 wt.%, in a molten state. Blended cement pastes were formulated using cement (70 wt.%) and the modified GCS (30 wt.%). The development of hydration heat and strength were examined using isothermal calorimetry and strength tests, respectively. The mineral composition and microstructure of hydration products for different reaction periods were examined using X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). Also, toxicity characteristic leaching procedure (TCLP) was performed on the samples. Results showed an increase in the hydration heat emission rate from the early hydration and the compressive strength of blended cement paste after curing for 28 days, indicating that the addition of CaO and Al2O3 in GCS improves pozzolanic activity. XRD and SEM-EDS analysis indicated that the modified GCS consumed more calcium hydroxide (CH) accompanied by increased generation of calcium silicate hydrate (C–S–H) gels in blended cement with a microstructure containing more gel phases and fewer pores, forming a more compact structure. Leaching of heavy metals of paste samples was lower than Environmental Protection Agency (EPA) limit. It is possible to apply the modified GCS as a sustainable material to promote cleaner production for cement and concrete industries.http://www.sciencedirect.com/science/article/pii/S2238785422003143Granulated copper slagModificationBlended cement pastePozzolanic activity |
| spellingShingle | Qinli Zhang Bingyi Zhang Yan Feng Chongchong Qi Qiusong Chen Chongchun Xiao Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 Journal of Materials Research and Technology Granulated copper slag Modification Blended cement paste Pozzolanic activity |
| title | Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 |
| title_full | Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 |
| title_fullStr | Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 |
| title_full_unstemmed | Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 |
| title_short | Hydration development of blended cement paste with granulated copper slag modified with CaO and Al2O3 |
| title_sort | hydration development of blended cement paste with granulated copper slag modified with cao and al2o3 |
| topic | Granulated copper slag Modification Blended cement paste Pozzolanic activity |
| url | http://www.sciencedirect.com/science/article/pii/S2238785422003143 |
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