Study of the recycling of solid barite wastes as main constituent in ceramic composition

Abstract

Large amounts of Solid Barite Wastes (SBWs) materials are discarded in the Boucaïd’s mine located in the North of Algeria ((Tissemsilt) producing an average of 50 wt% of barite rejects after the physico-chemical treatment. This work investigates the incorporation of solid barite waste (SBWs) as a raw material into a clay body, replacing feldspar material by up to 20 wt%. Ceramic pieces were produced at temperatures varying from 1200 to 1300°C. The technological properties of the ceramic pieces (e.g., linear shrinkage, apparent density, water absorption, and compressive strength) have been determined. The leaching toxicity of the fired pieces has also been determined. The results showed that SBWs could be used in ceramic materials (porcelain type), in the range up to 10 wt%, as a partial replacement for feldspar. Mineralogical analysis of SBWs, shows that it is mainly composed of calcite (22%), barite (25%), cerusite (13%) and hemimorphite (27%). After sintering, mullite, anorthite and quartz are the main mineralogical phases appeared at 1200 °C; when the temperature roses at 1300 °C, celcian phase appears, beside anorthite and quartz phases. The obtained ceramic samples exhibit better mechanical properties compared to the reference ceramic samples (0% SBWs). However, up to 10 wt% additions of SBWs in the ceramic bodies, micro-hardness and the Young's modulus have higher values, reaching 480 kg/mm2 and 41.27 GPa respectively at 1300 °C. Besides, the evaluation of the release of various chemical species (Pb2+ ,Zn2+, Ba2+and Cu2+) contained in the ceramic samples indicates successful inertization of the pollutants. The results show that solid barite wastes can be used as substituent of feldspar to produce eco- friendly ceramic materials.