{"title":"Sustainable utilization of clay minerals-rich engineering muck via alkali activation: Optimization of pore structure by thermal treatment","authors":"","doi":"10.1016/j.clay.2024.107491","DOIUrl":null,"url":null,"abstract":"<div><p>Engineering muck (EM) in South China is a typical construction waste, which has a low utilization rate. After the thermal treatment, this study prepares the EM-based geopolymers and evaluates the CO<sub>2</sub> emission. The calcined EM and the geopolymers were characterized through thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), and nuclear magnetic resonance (NMR) spectroscopy. The results showed that when the thermal treatment temperature was 850 °C, the dissolution of aluminum (Al) and silicon (Si) was adequate, significantly enhancing the reactivity of geopolymerization and thus forming a geopolymer with dense structures and excellent mechanical properties. Notably, the compressive strength at 7 days for the geopolymer exceeded 50 MPa, and the cumulative pore volume and pore size distribution were both minimal. In addition, an environmental implication analysis revealed that the recycled geopolymers could reduce carbon emissions by approximately 11–65 kg CO<sub>2</sub>/t when compared to conventional concretes, contributing towards low-carbon goals. The findings of this study propose a more environmentally friendly strategy for the treatment of the EM, contributing to the advancement of sustainable solid waste utilization.</p></div>","PeriodicalId":245,"journal":{"name":"Applied Clay Science","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Clay Science","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0169131724002394","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Engineering muck (EM) in South China is a typical construction waste, which has a low utilization rate. After the thermal treatment, this study prepares the EM-based geopolymers and evaluates the CO2 emission. The calcined EM and the geopolymers were characterized through thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), and nuclear magnetic resonance (NMR) spectroscopy. The results showed that when the thermal treatment temperature was 850 °C, the dissolution of aluminum (Al) and silicon (Si) was adequate, significantly enhancing the reactivity of geopolymerization and thus forming a geopolymer with dense structures and excellent mechanical properties. Notably, the compressive strength at 7 days for the geopolymer exceeded 50 MPa, and the cumulative pore volume and pore size distribution were both minimal. In addition, an environmental implication analysis revealed that the recycled geopolymers could reduce carbon emissions by approximately 11–65 kg CO2/t when compared to conventional concretes, contributing towards low-carbon goals. The findings of this study propose a more environmentally friendly strategy for the treatment of the EM, contributing to the advancement of sustainable solid waste utilization.
期刊介绍:
Applied Clay Science aims to be an international journal attracting high quality scientific papers on clays and clay minerals, including research papers, reviews, and technical notes. The journal covers typical subjects of Fundamental and Applied Clay Science such as:
• Synthesis and purification
• Structural, crystallographic and mineralogical properties of clays and clay minerals
• Thermal properties of clays and clay minerals
• Physico-chemical properties including i) surface and interface properties; ii) thermodynamic properties; iii) mechanical properties
• Interaction with water, with polar and apolar molecules
• Colloidal properties and rheology
• Adsorption, Intercalation, Ionic exchange
• Genesis and deposits of clay minerals
• Geology and geochemistry of clays
• Modification of clays and clay minerals properties by thermal and physical treatments
• Modification by chemical treatments with organic and inorganic molecules(organoclays, pillared clays)
• Modification by biological microorganisms. etc...