Dodecylbenzene sulfonic acid (DBSA) is one of the significant anionic surfactants that can be used as a cleaning agent in the daily chemical industry or chemical oil-displacing agents in tertiary oil recovery. The sulfonation of dodecylbenzene (DDB) is the predominant route to fabricate DBSA. In this paper, we introduce a continuous process and a cyclic process in microreactors to optimize the routine of DDB sulfonation using dilute liquid sulfur trioxide and compare the two processes systematically. By optimizing the flow rate, the SO₃/DDB molar ratio, the sulfonation temperature in the microreactor and the aging step, all the physicochemical indexes of product in continuous process can meet the standard of top grade with sulfonic acid contents up to 97 wt.% and the free oil and sulfuric acid contents down to 1.0 wt.%. Furthermore, the residence time of the reactants in the microreactor can be as low as 2.5 s, and the aging stage can be completed in less than one hour, which is a lot faster than the industrial process. In summary, we have optimized the whole process of the DBSA production so that it can have great potential in application to actual industrial production.

十二烷基苯磺酸（DBSA）是重要的阴离子表面活性剂之一，可在日常化学工业中用作清洁剂，或在三次采油中用作化学驱油剂。十二烷基苯（DDB）的磺化是制造DBSA的主要途径。在本文中，我们介绍了微反应器中的连续过程和循环过程，以优化使用稀液态三氧化硫进行DDB磺化的程序，并系统地比较了这两个过程。通过优化流速，SO ₃/ DDB摩尔比，微反应器中的磺化温度和老化步骤，连续过程中产品的所有理化指标均可以满足高档标准，其中磺酸含量最高可达97 wt。％，游离油和硫酸含量最高低至1.0重量％。此外，反应物在微反应器中的停留时间可以低至2.5 s，并且熟化阶段可以在不到一小时的时间内完成，这比工业过程要快得多。综上所述，我们优化了DBSA生产的整个过程，使其在实际工业生产中具有巨大的应用潜力。