非水条件下有机碱分解氯化铵回收氨的工艺  

Recovery technology of ammonia from non-aqueous decomposition of ammonia chloride by organic base

作　　者：元利峰[1] 陈献[1] 汤吉海[1] 崔咪芬[1] 乔旭[2] 徐高明[1] 

机构地区：[1]南京工业大学化学化工学院江苏省工业节水减排重点实验室,江苏南京210009 [2]南京工业大学化学化工学院材料化学工程国家重点实验室,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2013年第5期31-35,共5页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家科技支撑计划(2011BAE18B01);江苏省科技支撑计划(BE2011830)

摘　　要：采用有机碱在非水条件下将纯碱工业副产的NH4Cl分解为NH3和HCl,研究了在异丙醇溶剂中三辛胺(TOA)分解NH4Cl释放NH3的工艺,考察了反应温度、N2流量、TOA与NH4Cl摩尔比、异丙醇与TOA摩尔比、反应时间等对NH4Cl分解反应的影响。结果表明:NH4Cl处理量为0.1 mol时的最佳分解工艺条件为反应温度353 K、N2流量120 mL/min、TOA与NH4Cl摩尔比为1.4∶1、异丙醇与TOA摩尔比为7.1∶1、反应时间8.25 h。在最优条件下,NH3收率达到97%以上,且无废水排放。进一步探讨了极性溶剂下有机碱分解NH4Cl的反应机制,发现溶剂异丙醇中羟基与TOA中N原子上的孤对电子形成氢键,使TOA的碱性增强,与NH4Cl反应更容易释放出NH3。Ammonia （NH3 ） and hydrogen chloride （HC1） were recovered from non-aqueous decomposi- tion of by-product ammonia chloride （NH4C1） by organic base, and the technology of releasing NHz from NH4 C1 decomposition by trioctylamine （TOA） in isopropanol solvent was studied. The effects of reaction temperature, nitrogen （ N2 ） flow rate, molar ratio of TOA to NH4 C1, molar ratio of isopropanol to TOA, and reaction time on the yield of NH3 were investigated. The results showed that the optimal reaction con- ditions for the decomposition of O. 1 tool ammonia chloride were as follows： reaction temperature 353 K, N2 flow rate 120 mL/min, molar ratio of TOA to NH4C1 1.4： 1, molar ratio of isopropanol to TOA 7.1： 1, and reaction time 8.25 h. The yield of NH3 was above 97% under the optimal conditions. No waste water was discharged in this process. The reaction mechanism of NH4C1 decomposition by organic base in polar solvent was discussed. It was found that the hydroxyl group in isopropanol and the lone pair electrons of nitrogen atom in TOA formed a hydrogen bond, which enhanced the basieity of TOA, thus making the ammonia more easily release in decomposition of ammonium chloride.

关 键 词：NH4CL 分解 有机碱 三辛胺 

分 类 号：TQ110.7[化学工程—无机化工]