Mechanochemical destruction of Dechlorane Plus with calcium oxide

Dechlorane Plus (DP) was co-ground with calcium oxide (CaO) powder in a planetary ball mill at room temperature. A mechanochemical reaction was induced, resulting in the decomposition of DP through dechlorination. The influences of both the charge ratio and content of CaO were investigated. The co-ground samples were characterized and analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, gas chromatography/mass spectrometry (GC/MS), and ion chromatography (IC). With the increase in grinding time, the remained DP decreased and finally was completely destroyed after 4 h grinding time in the mixture with a CaO/DP ratio of 25:1 and a charge ratio of 36:1. At the same time, the water-soluble amount of chlorine increased correspondingly and reached 88.6%, demonstrating that dechlorination is the major degradation mechanism. The main degradation products in the final reaction were carbon and CaCl2, beside the excess CaO. The first carbon structure appeared after grinding treatment was graphite, while the second was amorphous carbon.