Magnesium oxide production from chrysotile asbestos detoxification with oxalic acid treatment

This article describes the detoxification of pure chrysotile (Chr) asbestos by following an acid leaching treatment with oxalic acid dihydrate (Oxac) (H2C2O4·2H2O). Oxac was chosen due to its low environmental impact (or toxicity) and cost. We demonstrate the effectiveness of different concentrations of Oxac as proposed formulations. The results from FTIR, XRD and optical microscopy analyses indicated that all the applied treatments destructed the Chr structure while a new biomaterial, Glushinskite (Gls) was formed by the reaction between Oxac with the outer Brucite (Brc) (MgO2) layer surface of Chr. Oxac 0.05 M was selected as the optimal concentration for an eight-day treatment for the detoxification. The heating of the supernatant of the above-treated solution at 480 °C, yielded MgO in a considerable concentration (8.29% w/w). According to the energy consumption study the whole applied procedure is viable with an economic profit up to 4.3% and a low cost method of detoxification on the operation of a potential asbestos waste management site.