Production of brown inorganic pigments with spinel structure using spent zinc-carbon batteries

Abstract

In recent years, there has been an increase in the production of zinc-carbon batteries to fulfil the demand for portable energy. This has led to an increase in the spent batteries disposal, which can cause environmental problems. In this study, inorganic brown pigments were produced using electrode materials from spent zinc-carbon batteries with the aim of recycling this residue as it is toxic to the environment and human health when disposed incorrectly. The pigments were produced by the solid state reaction between the oxides mixtures from spent batteries and chromium oxide and heat treated at 1200 °C for two hours. The produced pigments were stable and showed good colour and opacity when applied to ceramic pieces at a decorative burning temperature (850 °C). At 1050 °C, only the ZMC100 sample (with initial composition having ZnMn2O4 : Cr2O3 molar ratio of 1 : 1) showed stability. A good result was obtained when the produced samples were compared with the standards produced by solid-state reaction of the pure commercial oxides. The compounds produced during battery discharge, favoured the formation of ZnMn2O4 with higher purity at low temperatures. Hence, the pigment produced using dry electrode materials as a precursor was more crystalline than the synthetic sample obtained under the same conditions.

Keywords

• zinc-carbon
• spent batteries
• recycle
• spinel structure
• brown pigment