**5. Conclusions**

In this work, the effect of S8 deposition on the corrosion behavior of L360 pipeline steel in CO2−Cl<sup>−</sup> medium at different pH values at 60 ◦C was studied using electrochemical measurements and surface analysis.

(1) The corrosion current densities of the electrode coated with S8 were larger, and the *R*ct value was 1/27 that of the bare electrode. Pitting corrosion cavities were observed on the surface of the electrode under S8 deposition in acidic conditions, and the bare electrode suffered uniform corrosion.

(2) The *L*CII and morphology further proved that the deposition of S8 enhanced localized corrosion at pH = 3.10.

(3) The deposition of S8 not only acidized the solution but also increased the difference in the corrosion environment inside and outside of the S8 deposition layer, resulting in serious pitting corrosion under S8 deposition.

**Author Contributions:** Formal analysis, C.Q. and F.C.; Investigation, S.Z.; Resources, T.Y. and B.Y.; Supervision, Y.L.; writing—original draft preparation, F.W. and J.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was funded by the National Natural Science Foundation of China (21808182, 51974245). Key Laboratory Scientific Research Project of Shaanxi Provincial Department of Education (18JS088).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
