As a certain method for decomposing harmful asbestos, it is proposed to dissolve the asbestos in molten slag of the pyrometallurgical smelting furnaces. Several dissolution tests have been achieved so far, and it has been suggested that the crystalline structures of the asbestos were decomposed before dissolving into slag. In this study, asbestos samples composed of chrysotile or crocidolite were heated in temperature range 800-1000°C, and the times required to decompose the crystalline structures of the asbestos were examined using X-ray diffraction analysis. Temperature higher than 900°C was required to wipe off the peaks of crocidolite, though chrysotile could be decomposed at 700°C. For both samples containing chrysotile and crocidolite, the peaks of asbestos in the X-ray diffraction patterns disappeared almost within 90 seconds when heated at 1000°C. However, the needle shapes were still maintained in both samples when they were simply heated at 1000°C.
