Detoxification of persistent organic compounds by a combination of plasma decomposition with in-situ halogen absorption

本文研究了在N_2、O_2N_2和H_2-N_2气氛中，有机卤化物气体的低温等离子体分解行为。此外，为了抑制卤素副产物的形成，并通过原位捕获卤素物种来有效地解毒卤化物，采用等离子体分解结合碱性吸收剂原位气体吸收的技术研究了有机卤化物气体的分解。（CCl_4，CHF_3，CHClF_2）在O_2-N_2气氛中的分解率低于在N_2气氛中的分解率。卤素气体结构中的碳（C）氧化生成的CO_2量随O_2浓度的增加而增加。CHClF_2在N_2气氛下分解时，有CCl_2F_2、HF、HCl、F_2和Cl_2生成;在O_2-N_2气氛下分解时，有COF_2和COCl_2生成。cas中 关于我们 在H_2-N_2气氛下，CF_4、CHF_3、CHClF_2和SF_6的等离子体分解率高于N_2气氛下。而在H_2存在下，CHF_3的分解率降低。SF_6在H_2-N_2气氛下分解时，除生成F_2外，还生成H_2S和HF，将等离子体分解与Ca（OH）_2吸收剂的原位气体吸收相结合，使CHClF_2在O_2-N_2气氛下和CHF_3在H_2-N_2气氛下分解时，卤化物的分解率提高，与不加Ca（OH）_2的情况相比。在O_2-N_2气氛下，原位碱性吸收剂存在下CHClF_2等离子体分解过程中CO_2的生成量高于无碱性吸收剂时的CO_2生成量。此外，在CHClF_2的等离子体分解过程中，结合原位气体吸收，可以有效地抑制出口气体中HF和COCl_2等卤素副产物的生成，从而证明了在等离子体反应场中原位存在碱性吸收剂以实现卤素气体的有效等离子体分解和有害副产物去除的可能性。少

In this research, the behavior of non-thermal plasma decomposition of organic halide gases in N_2,O_2N_2 and H_2-N_2 atmospheres was studied. In addition, for the purpose of inhibition of the formation of halogen byproducts and effective detoxification of halides by the in-situ capture of the halogen species, the decomposition of organic halide gases was investigated using a technique of plasma decomposition combined with in-situ gas absorption by alkaline absorbent.On the plasma decomposition of halide gases (CCl_4,CHF_3 and CHClF_2) in the O_2-N_2 atmosphere, the decomposition ratios of halide gases were lower compared to those in N_2 atmosphere. The amount of CO_2 formed by the oxidation of the carbon (C) in the structure of halide gases was increased with the increase of the concentration of O_2. During the decomposition of CHClF_2 under N_2 atmosphere, CCl_2F_2,HF, HCl,F_2 and Cl_2 were detected, while, in addition, COF_2 and COCl_2 were formed under O_2-N_2 atmosphere. In the cas … More e of the plasma decomposition of CF_4,CHF_3,CHClF_2 and SF_6 in H_2-N_2 atmosphere, the decomposition ratios of CF_4,CHC1lF_2 and SF_6 were higher compared to those in N_2 atmosphere. However, the decomposition ratio of CHF_3 decreased in the presence of H_2. H_2S and HF were formed as the byproducts in the decomposition of SF_6 in H_2-N_2 atmosphere, in addition to F_2 formed in N_2 atmosphere.When the plasma decomposition was incorporated with in-situ gas absorption by Ca(OH)_2 absorbent on the decomposition of CHClF_2 in O_2-N_2 atmosphere and CHF_3 in H_2-N_2 atmosphere, the decomposition ratios of halides increased, compared to that without Ca(OH)_2. In O_2-N_2 atmosphere, the amount of CO_2 formed during the plasma decomposition of CHClF_2 in the presence of in-situ alkaline absorbent was higher than that without alkaline absorbent. Moreover, it was found that the generation of the halogen byproducts such as HF and COCl_2 in outlet gas was significantly inhibited in plasma decomposition of CHClF_2 incorporated with in-situ gas absorption.As a result, our work demonstrated the possibility of in-situ alkaline absorbent present in the plasma reaction field to achieve the effective plasma decomposition of halide gases and removal of harmful byproducts. Less