Round 1

Reviewer 1 Report

Referee's Report

Manuscript ID: colloids-1724718

Journal: Colloids and Interfaces (ISSN 2504-5377)

Title: Oscillatory structural force and its impact on enhanced oil recovery using nanofluid

Recommendation:  Major Revision

Reviewer's comments:

This paper discussed the significant role of the oscillatory structural force in enhanced oil recovery using hydrophilic nanoparticles via wettability alteration by means of enhanced spreading of the nanofluid and foam stabilization. Paper is of current interest and falls in the scope of the journal, however, there are the following suggestions authors should address and then I welcome for publication:

1. The title is informative, but it is very general, revise that by including the main novelty and the significant studied effects.
2. The abstract can be written in a more interesting fashion with the significance of the study, the aim of the study, the research methodology, and the major conclusion of the study.
3. In the abstract section, the authors said, "Nanofluid has been subject of research interest in many practical applications like enhanced oil recovery.", needs to correct it is not good.
4. Add some important numerical outcomes to the final abstract section.
5. The resolution of a graphical abstract figure needs to improve.
6. In the Introduction section, try to avoid groups of used references and explain the study features and results of each work separately, such as [3-5], [6-8], [11-14], [17-19], etc.
7. The last paragraph of the Introduction section needs to be reformulated to clarify the innovation of the current study and the difference between this study and previous studies, which prompted the authors to do the current study.
8. There have been several instances of punctuation mistakes. The manuscript should be reviewed because it contains some grammatical English errors. The manuscript requires proofreading.
9. Clarify and discuss the motivation of this study, and the novelty and the significance of the results obtained here.
10. The sentence "After three pore volumes brine flooding and before the nanofluid…" needs clearer.
11. Expand the discussion to highlight the relevance and interest of this work for its aimed scientific community.
12. The conclusion is very informative but at the end of the conclusion kindly state the further openings of the upcoming researchers. Conclusions section should be improved by write it in abbreviated points.

Author Response

Please see the attached responses.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript titled "Oscillatory structural force and its impact on enhanced oil recovery using nanofluid" is about the role of the oscillatory structural force in enhanced oil recovery using hydrophilic nanoparticles. At the present, hydrophilic nanoparticle composites are the most promising candidate to replace conventional EOR, so this topic may be interesting and useful for many readers. The authors used a wide range of methods to characterize obtained materials. However, some interpretations are questionable, and the authors omitted important experimental details, which makes it difficult to evaluate the results of the work.

There are the following comments for the current manuscript:

1) how is related the oscillatory structural pressure to contact angle? how is verified contact angle experimentally by measuring the film-meniscus profile? This is necessary to compare your results with those previously reported.

2) Line 212: «there is a pressure gradient pointing from the bulk to the vertex, which drives the spreading of the nanofluid toward the vertex. ». I think that to confirm the uniqueness of the results it would be useful to add the comparison of the results of this work with the articles that used similar materials. A brief discussion.

3) Authors should add more details in the theoretical part, they also, need to experimental part to validate the work i.e. XPS, SEM, and ....

4) More detail about Oil displacement in 2D glass pore should be given so that other researchers can repeat the results.

5) Submit a relevant graphical abstract or schematic of the research approach; this may enhance the impact of your paper.

6) A few more citations to the most recent papers would help clarify the position of this manuscript. to improve the quality, the following recommendations can be incorporated.

"Improved oil recovery by the efficiency of nano-particle in imbibition mechanism." In 2nd EAGE international conference KazGeo, pp. cp-315. European Association of Geoscientists & Engineers, 2012.

"Nanotechnology in enhanced oil recovery." Processes 8, no. 9 (2020): 1073.

7) I highly recommend checking the references list and decreasing the number of self-citations, especially in the Introduction.

Author Response

Please see the attached responses.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have satisfactorily responded to all the questions and made the necessary changes to the manuscript. I have no further questions and suggest the acceptance of the revised manuscript.

Reviewer 2 Report

The manuscript quality has been improved.