Mg_2(OH)_3C1.2H_2O CHLORINATION

摘要

The kinetics of the hydrochlorination of Mg_2(OH)_3C1.2H_2O with HCl gas were measured. The Mg_2(OH)_3C1.2H_2O was isolated from the feed of a commercial electrolytic magnesium production process by methanol leaching. It was found that the isolated Mg_2(OH)_3C1.2H_2O particles had an average diameter of 150 micron. Over 95 % conversion to anhydrous MgCl_2 was observed within 30 minutes by contacting the Mg_2(OH)_3C1.2H_2O particles with HCl gas at temperatures in the range from 250 to 350℃. It was found that the rate and extent of chlorination of Mg_2(OH)_3C1.2H_2O was independent of temperature. XRD spectra of samples at various extents of conversion and the mass loss data suggested that Mg_2(OH)_3C1.2H_2O first lost its crystalline water and then directly converted into MgCl_2 without first decomposing to MgO.