Effect of the Ti-extracted residue on compressive strength and microstructural properties of modified cement mortar

Keke Sun, Dongxing Xuan, Jingjing Li, Guangxiang Ji, Chi Sun Poon, Shuping Wang, Xiaoqin Peng, Xuewei Lv, Guanwu Zeng

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

The Ti-extracted residue is a metallurgical solid waste and its utilization is limited in cement-based materials due to its high amount of chloride salts. In this study, the washed and unwashed Ti-extracted residues were used to replace high-quality supplementary cementitious materials, and the compressive strength and microstructural properties of the prepared specimens were studied. Incorporating the Ti-extracted residue in the cement paste can increase the early compressive strength due to the acceleration effect of the chloride salt on the hydration process, but the washed Ti-extracted residue reduced the later compressive strength due to its lower reactivity. Meanwhile, the Ti-extracted residue with its hydraulic and pozzolanic effects contributed to the formation of the C-S-H gel with a low Ca/Si ratio, which resulted in the consumption of calcium hydroxide and the lowering of the indentation modulus and hardness of the C-S-H gel. In addition, the leaching test demonstrated that the washed Ti-extracted residue was harmless to the environment, and the chlorine ion of the Ti-extracted residue can be physically and chemically bonded. Therefore, the washing method is an effective way to remove the soluble chlorine of the Ti-extracted residue and decrease its potential risk to environment. This research finding facilitated the recycling of the Ti-extracted residue as supplementary cementitious materials in cement-based materials.

Original languageEnglish
Article number126190
JournalConstruction and Building Materials
Volume320
DOIs
Publication statusPublished - 21 Feb 2022

Keywords

  • Hydration reaction
  • Micromechanical property
  • Supplementary cementitious materials
  • Ti-extracted residue
  • Waste management

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Building and Construction
  • Materials Science(all)

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