Review Reports

Round 1

Reviewer 1 Report

In this manuscript, Majid D. et al optimized the index of dispersant formulation and summarized non-chemical dispersants. Before considering for publication in any journal, the following items should be addressed carefully.

1. The title of Part 5 “Formulation of dispersant” is inappropriate, the authors emphasize that HLB and HLD can be used to optimize the formulation, so the title is not very accurate.

2. The authors summarized the optimization indicators in Part 5. I think the types of emulsions is inappropriate here.

3. The surfactant examples in Part 4 are not sufficient. The author should add another relevant example.

4. I don't think biosurfactants should be mentioned in Plant-based surfactants because biosurfactant may also come from other ways, such as rhamnolipd.

5. The Figure 7 is blurry.

6. Many errors occurred in the manuscript, such as “oil trade in early 19th century,” on line 24, page 1, “spillage” on line36, page 1, “- particularly the intertidal zones -” on line 60, page 2, and the spelling errors “On the country” on line 270, page 7. Please correct them.

Author Response

In this manuscript, Majid D. et al optimized the index of dispersant formulation and summarized non-chemical dispersants. Before considering for publication in any journal, the following items should be addressed carefully.

1. The title of Part 5 “Formulation of dispersant” is inappropriate, the authors emphasize that HLB and HLD can be used to optimize the formulation, so the title is not very accurate.

Thank you. We agree with our reviewer and the new title for this section is changed to “Factors to determine the effectiveness of oil dispersants” in the revised manuscript.

2. The authors summarized the optimization indicators in Part 5. I think the types of emulsions is inappropriate here.

We introduced different types of emulsion in this review to discuss what types are usually found in the dispersant of crude oil. Therefore, we prefer to keep this categorization in the revised manuscript because it is fundamental to the discussion made in the next paragraph (under Figure 3). It makes it easier for the readers to follow the plotted discussion in this manuscript.

3. The surfactant examples in Part 4 are not sufficient. The author should add another relevant example.

Other examples are included in this part of the revised manuscript.

4. I don't think biosurfactants should be mentioned in Plant-based surfactants because biosurfactant may also come from other ways, such as rhamnolipd.

We agree with our reviewer, and thus, deleted the biosurfactant discussion that was included in the plant-based surfactants.  Biosurfactants are discussed seperatly in the part 6.4 of this manuscript.

5. The Figure 7 is blurry.

This figure is replaced with the one with high quality in the revised manuscript.

6. Many errors occurred in the manuscript, such as “oil trade in early 19th century,” on line 24, page 1, “spillage” on line36, page 1, “- particularly the intertidal zones -” on line 60, page 2, and the spelling errors “On the country” on line 270, page 7. Please correct them.

Thank you. We screened the entire of the manuscript for these types of errors and corrected them where applicable in the revised manuscript.

 

Reviewer 2 Report

To the Authors

This is a well-written work dealing with the important topic of marine oil spills removal procedures with the use of dispersing agents. The authors made efforts to describe the modern state-of the-art in view of mechanisms of dispersant action, the used dispersants solvents, the factors affecting the dispersion efficiency, mechanisms and types of O/W and W/O emulsions formed with various surfactants, and theoretical consideration of the lipohydrophilic balances that helps in the formulation of the amphiphilic mixtures for disintegration of the oil spills. Finally, certain new approaches were discussed; they are solid dispersants such as carbon materials, natural minerals (montmorillonite), as well as bio-derived environmentally benign ones and biosurfactants. This is a really interesting article; the general layout is correct, the technical language is as well. In my opinion, this nice work meets the scope of the journal; thus, it deserves to be published in the Journal of Marine Science and Engineering as it is. Just two minute issues to be addressed:

1/ Lines 208-210: “To lower the DOR and to 208 improve the application effectiveness, oxygenated compounds with low toxicity such as 209 glycols and glycol ethers…” In fact, ethylene glycol is really toxic substance. For instance, for this reason, the manufacturers of automotive cooling fluids replace ethylene glycol, by propylene glycol which has lower toxicity. Please clarify this point.

2/ Just a technical issue: the quality of Fig. 7 should be higher.

Author Response

1/ Lines 208-210: “To lower the DOR and to 208 improve the application effectiveness, oxygenated compounds with low toxicity such as 209 glycols and glycol ethers…” In fact, ethylene glycol is really toxic substance. For instance, for this reason, the manufacturers of automotive cooling fluids replace ethylene glycol, by propylene glycol which has lower toxicity. Please clarify this point.

Yes, we agree with our reviewer. We double checked with the reference and find out that it is actually propylene/isopropylene glycols. Therefore, we made it more specific in the revised version of this manuscript.

2/ Just a technical issue: the quality of Fig. 7 should be higher.

This figure is replaced with the one with high quality in the revised manuscript.