Strength Characteristics of Cement-Modified Iron Tailings and Their Adsorption on Graphene Oxide

Abstract

To explore the mechanical properties of cement-modified iron tailings (CIT) and its adsorption on graphene oxide (GO), the unconfined compressive strength (UCS) tests of CIT with 10% cement were carried out for 7 and 28 days. CIT adsorption of GO was carried out under the conditions of different pH, CIT dosage, and GO initial concentration. The micro characterization of CIT adsorption of GO was carried out by SEM, TEM, AFM, EDS, FT-IR, XRD, and XPS. The results show that: (1) the CIT strength of 28 d curing age is 1202 kPa is twice of 7 d. (2) At the same pH, the GO adsorption effect of CIT at 7 days curing age was better than that at 28 days. When pH is 6, CIT content is 50 mg, and GO initial concentration is 100 mg.L-1, CIT has the best adsorption effect on the GO, and the removal rate reached 93.5%. (3) Through microscopic characterization, it can be concluded that the bound water in the CIT structure and the asymmetric stretching vibration of the O-H bond in hydrated calcium silicate (C-S-H) are the main factors affecting the adsorption of GO. The above research results show that CIT not only has good strength properties but also has good adsorption properties for GO. CIT is a potential environmental treatment material.

Keywords

• cement-modified iron tailings, graphene oxide, mechanical properties, adsorption characteristics, micro mechanism