Higher degree disposal of hardly decomposed organic halogen compounds for non-toxicity.

多氯联苯等含卤素的有机化合物危害大，对环境污染大，不易分解，因此对其进行处理十分重要。本研究的目的是将化合物完全分解。这个过程中最困难的工作是将卤素转化为无害的形式。因此，我们选择了具有碱性的熔盐作为反应介质。该方法除具有较强的卤素吸收性外，还具有在常压下和温度适中的优点。在本研究中，使用的熔盐为强碱性KOH-K_2CO_3或NaOH-Na_2CO_3混合物。将作为液体的样品化合物与载气（模拟空气、氧气或氮气）一起注入熔盐。采用气相色谱-质谱联用仪（GC/MS）对尾气进行分析。分别控制样品液和载气的流速，得到不同的流速和浓度。在400 ~ 700℃的温度下，对四氯化碳、一氯苯、邻二氯苯、1,2,3三氯苯和4,4'二氯联苯进行了实验。由于1,2,3三氯苯和4,4'二氯联苯在室温下为固体，因此将它们溶解在有机溶剂中。结果表明，所有化合物在600 ~ 700℃时的分解效率均高于99.998%。在以氮气为载气的情况下，在废气中发现了一些中间化合物。但是，它们都是除氯以外的化合物。这表明，即使化合物没有完全分解成H_2O和CO_2，也能有效地去除化合物中的氯。从使有害化合物无害化的观点出发，这是一个很好的发现。综上所述，该方法对含卤素的有害有机化合物的分解是非常有效的。

As the organic compounds containing halogens such as PCB are very harmful, environmentally contaminative and hardly decomposable, it is very important to dispose the compounds. The purpose of this study is to decompose the compounds completely. Most difficult work in the process is to convert the halogen to harmless form. Therefore, we selected the molten salts with basic property as the reaction medium. This method has the advantages that are under the atmospheric pressure and the moderated temperatures n addition to strong absorbability of halogens.In this study, the molten salts used were strongly basic KOH-K_2CO_3 or NaOH-Na_2CO_3 mixtures. The sample compounds as the liquids were injected into the molten salts together with the carrier gas which were imitation air, oxygen or nitrogen. The exhaust was analyzed by means of the gas chromatography mass spectrometer (GC/MS). The flow rates of the sample liquid and carrier gas were controlled independently to obtain various flow rates and the concentrations.The experiments were carried out for CCl_4, monochlorobenzene, o-dichlorobenzene, 1,2,3 trichlorobenzene and 4,4' dichlorobiphenyl at the temperatures of 400-700℃. As 1,2,3 trichlorobenzene and 4,4' dichlorobiphenyl are solids in room temperature, they were dissolved into the organic solvent.As the results, higher than 99.998% of the decomposition efficiencies were obtained for all the compounds at 600-700℃. In the case of nitrogen as the carrier gas, some intermediate compounds were found in the exhaust. However, all of them were the compounds excluding the chlorine. It suggests that the chlorine in the compounds was removed effectively even if the compounds were not completely decomposed to H_2O and CO_2. It is very good finding based on the viewpoint to make the harmful compounds harmless. Totally, it is considered that this method is very effective to decompose the harmful organic compounds containing halogen.