Alkali Activation of Copper and Nickel Slag Composite Cementitious Materials

Abstract

Alkali-activated copper and nickel slag cementitious materials (ACNCMs) are composite cementitious materials with CNS (copper and nickel slag) as the main materials and GGBFS (ground-granulated blast-furnace slag) as a mineral admixture. In this paper, the activity indexes of CNS with different grinding times were studied using CNS to replace a portion of cement. NaOH, Na2SO4, and Na2SiO3 activators were used to study the alkaline solution of the CNS glass phase. The effects of the fineness of CNS and the type of activator on the hydration of ACNCMs were investigated via physical/mechanical grinding and chemical activation. The hydration products of ACNCMs were analyzed via XRD, SEM, FT-IR, TG, and MIP. The results of the study revealed that the activity indexes of CNS ground with different grinding times (10, 30 and 50 min) were 0.662, 0.689, and 0.703, respectively. When Na2SiO3 was used as the activator, the glass phase dissolved the most Si4+, Al3+, and Ca2+, and the respective concentrations in the solution were found to be 2419, 39.55, and 3.38 mg/L. Additionally, the hydration products of ACNCMs were found to have a 28-day compressive strength of up to 84 MPa.

Carbonation and Chloride Ions’ Penetration of Alkali-Activated Materials: A Review

“…Numerous investigations have found that the precursor composition in AAMs [58][59][60][61][62][63][64] has an obvious influence on the resistance to carbonation. This is mainly attributed to differences in the content of calcium, silicon, magnesium, and aluminum in the precursors and, thus, variations in the hydration products.…”

Strength Characteristics and Microstructure Analysis of Alkali-Activated Slag–Fly Ash Cementitious Material

“…In recent years, the research on alkali-activated cementitious materials mainly focuses on two directions. First, continue to study alkali-activated slag cementitious materials to improve their properties and expand their applications [ 21 , 22 , 23 ]; Second, other solid wastes with alkali-activated cementitious properties are used to prepare new alkali-activated cementitious materials, such as silicomanganese slag, copper and nickel slag, red mud-iron tailings, copper slag, nickel slag, and ferronickel slag [ 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”

Environmental Benefit Assessment of Blended Cement with Modified Granulated Copper Slag

“…Mussapyrova, et al (2021) [ 11 ] used mechanical activation on GCS. Zhang, et al (2020) [ 12 ] investigated the properties of alkali-activated GCS cementitious materials using sodium hydroxide (NaOH) and sodium sulphate (Na 2 SO 4 ) solutions. These methods usually induce intensive energy consumption and were not very effective.…”