A systematic study on solid-state synthesis of monticellite (CaMgSiO4) based ceramic powders obtained from boron derivative waste

Abstract

Solid-state synthesis of monticellite based ceramic powders from boron derivative waste in an eco-friendly route and the investigation of phase transformation mechanisms were studied. The heat-treatment of boron derivative waste, mainly composed of dolomite, calcite and quartz, was systematically carried out at 650 °C and 800 °C for various dwell times between 1 min and 4 h. The heat-treatment temperatures were selected considering TG-DTA curves of waste and ΔG – T diagrams obtained using FactSage Thermochemical Software. XRF, XRD, FTIR, TG-DTA and SEM analysis, particle size measurement and crystallite size determination carried out extensively. The obtained results showed that monticellite based ceramic powder synthesized at 800 °C for 4 h was composed of monticellite, akermanite, diopside, calcium magnesium borate and zeolite. The calcination of dolomite was completed both at 650 °C for 1 h and up to 800 °C, and calcite was decomposed at 800 °C for 30 min. Both diopside and monticellite were firstly detected at 650 °C for 30 min and at 800 °C for 1 min. Also, akermanite was presented at 800 °C for 1 min. The presented method offers the lowest temperature (800 °C) in literature for synthesis of monticellite and akermanite which reduces the energy consumption during heat-treatment.