**5. Conclusions**

In this paper, a novel process for a single reactive distillation column with excess reactant circulating internally is proposed for the production of butyric anhydride. Two applications with di fferent reactant pre-excesses are proposed, and the corresponding simulation method is also presented. On the basis of the simulation, the proposed SRDC process is compared to the traditional two-column process, and the results show the economical superiority of the SRDC. A more detailed analysis of the proposed process will be presented in the future.

**Author Contributions:** Conceptualization, S.T.; methodology, S.T.; software, F.J.; validation, G.C. and S.X.; formal analysis, F.J. and X.G.; investigation, G.C. and S.X.; resources, S.T.; data curation, F.J.; writing-original draft preparation, S.T. and F.J.; writing-review and editing, G.C., F.J., X.G., S.X., and S.T.; supervision, S.X.; project administration, G.C., F.J., X.G., S.X. and S.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work is supported by the National Natural Science Foundation of China (No. 21776145). The Innovation and Training Plan of the University Students in Qingdao University of Science and Technology (No. 201810426125).

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
