重烷基苯磺酸产品脱除游离酸的工艺研究

Removal of Free Acid from Heavy Alkyl Benzenesulfonic Acid Products

三氧化硫膜式磺化法生产重烷基苯磺酸时,过量的部分三氧化硫不可避免的会以游离硫酸的形式残留在磺酸产品中,对磺酸盐产品性能产生影响。“多层级逆向带吹”工艺通过向上均匀分布的废热空气与向下均匀分布的磺酸料液充分接触,将料液中夹带的三氧化硫通过排风管吹带至尾气管线。料液按照游离酸含量要求进行2层级及以上的逆向带吹,可有效脱除过量的三氧化硫,进而控制产品中游离酸的含量。当重烷基苯磺酸进料酸含量(以H_(2)SO_(4)计)在3.8%、进料流量为1 t/h,进行2层级逆向带吹工艺时,考察了废热空气温度、流量对脱酸率的影响,结果表明:当废热空气在70℃、流量为800 m^(3)/h,可处理至出料酸含量(以H_(2)SO_(4)计)约0.5%,平均脱酸率为86.8%。

the production of heavy alkyl benzenesulfonic acid by sulfur-trioxide membrane sulfonation,excessive sulfur trioxide will inevitably remain in sulfonic acid products in the form of free sulfuric acid,which will affect the performance of sulfonic acid products.“Multi-level reverse blowing”process,through the upward uniform distribution of waste hot air and downward uniform distribution of sulfonic acid feed liquid full contact,the feed liquid entailed sulfur trioxide through the exhaust pipe blowing to the tail gas pipeline.In accordance with the requirements of free acid content in the feed liquid,reverse blowing level 2 or above can effectively remove excess sulfur trioxide,and then control the content of free acid in the product.When the feed acid content of heavy alkyl benzene sulfonic acid(calculated by H_(2)SO_(4))is 3.8%,the feed flow is 1 t/h,and the two-level reverse strip blowing process is carried out,the effects of waste heat air temperature and flow rate on the deacidif ication rate are investigated.The results show that:when the waste hot air is at 70℃and the flow rate is 800 m^(3)/h,the effluent acid content(calculated by H_(2)SO_(4))can be treated to about 0.5%,and the average deacidif ication rate is 86.8%.