磷酸中臭氧催化氧化除氯  

Removal of Chloride Ion from Phosphoric Acid via Ozone Catalysis Oxidation

作　　者：张人元[1] 刘中清[1] 王琴[1] 张强[1] 马雪阳 刘维燥 梁斌[1] 李春[1] 

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《过程工程学报》2015年第1期106-110,共5页The Chinese Journal of Process Engineering

摘　　要：对磷酸体系中臭氧氧化除氯离子进行了实验研究,考察了磷酸浓度、添加过渡金属铁(III)、铜(II)和钴(II)离子及反应温度和时间对臭氧除氯的影响.结果表明,氢离子对臭氧除氯具有明显的催化作用,在磷酸浓度≥80%(ω)、反应温度70℃下反应1 h,氯离子浓度从1000 mg/L降至5 mg/L,达到工业级磷酸国家标准(GB/T 2092-2008)对氯离子含量的要求;铁(III)、铜(II)和钴(II)离子也可催化臭氧氧化氯离子,当磷酸溶液中铁(III)浓度≥500 mg/L时,在其他条件相同的情况下氯离子含量达标要求的磷酸浓度可降至60%(ω);而当磷酸溶液中钴(II)浓度为500 mg/L时,即使在约20%(ω)磷酸溶液中氯离子含量也可达标,从而可免除湿法磷酸浓缩预处理.将上述结果应用于脱除工业湿法磷酸中的氯离子,也得到了进一步证实.The removal of chloride ion from phosphoric acid system by ozone catalyzing oxidation was experimentally studied with focus on the effects of phosphoric acid concentration, addition of transition metallic ions of Fe^3＋, Cu^2＋, and Co^2＋, and reaction temperature and time. The results indicated that the H＋ dissociated from phosphoric acid could significantly catalyze the oxidation of chloride, resulting in Cl2 evolution, and the concentration of Cl^- was decreased from 1 000 to 5 mg/L at the concentration of phosphoric acid over 80%（ω） and reaction temperature 70 ℃ for 1 h, which meets the quality requirements of technical-grade phosphoric acid Chinese national standard（GB/T 2092-2008） for chloride content. The oxidation could also be catalyzed by Fe^3＋, Cu^2＋ and Co^2＋ ions. With Fe^3＋ concentration ≥500 mg/L and under the otherwise same conditions, the phosphoric acid concentration required for chlorine ion to reach the standard could be reduced to 60%（ω）, while the acid concentration could be further reduced to 20%（ω） upon using Co^2＋concentration of 500 mg/L in the presence of Fe^3＋, thus the concentration section of phosphoric acid could be omitted. The results were further confirmed upon the application in removal of chloride ion from commercial wet process phosphoric acid.

关 键 词：磷酸 氯离子 臭氧 氧化 脱氯 过渡金属 

分 类 号：TQ126.35[化学工程—无机化工]