热氧化分解法处理烷基化废硫酸再生研究

Study on regeneration of waste sulfuric acid of alkylation by thermal oxidation decomposition

采用热氧化分解法处理烷基化废硫酸,考察反应温度、氧化剂投加量及投加方式、反应时间等因素对烷基化废硫酸溶液色度、COD去除率、再生硫酸含量和硫酸回收率等质量指标的影响。结果表明,加入氧化剂H_2O_2对烷基化废硫酸溶液色度和COD的去除影响不大,而HNO_3和HClO_4的加入对色度和COD的去除影响显著;按0.1 mL/次加入体积分数为2%的HNO_3,在280℃下反应2 h得到无色透明的再生硫酸,质量分数达97.5%,回收率达76.8%;按0.1 mL/次加入体积分数为2%的HClO_4,在280℃下反应1.5 h得到再生硫酸,质量分数达96.7%,回收率达80.2%。通过该方法回收得到高浓度的再生硫酸,可回用到烷基化装置或其他工业。

The method of thermal oxidation could be adopted on treating waste sulfuric acid of alkylation. The effects of reaction temperature, oxidant dosage and adding method, reaction time and other factors on chroma, rate of COD removal, content of recycled sulfuric acid and recovery rate of waste sulfuric acid solution were investigated. The results show that addition of oxidant H2O2 has little effect on the chroma and COD removal of the waste sulfuric acid solution of alkylation, but the addition of HNO3 and HCIO4 has significant effects on the removal of chroma and COD. Putting volume fraction 2% of HNO3 （0. 1 mL each time） into waste sulfuric acid under 280℃ for 2 hours, the colorless and transparent regenerated sulfuric acid were obtained. The mass percent content of regenerated sulfuric acid was up to 97.5% and the recovery rate was 76.8% Putting volume fraction 2% of HC104 （0.1 mL each time） into waste sulfuric acid under 280℃ for 1.5 hours, the regenerated sulfuric acid was obtained with 96.7% of the mass percent content and 80.2% of the recovery rate. The high concentration of regenerated sulfuric acid can be recovered by the method, and can be reused in the alkylation unit or other industries.