From Waste to Energy: Cooking Oil Recycling for Biodiesel in Barranquilla, Colombia
Round 1
Reviewer 1 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsReview attached
Comments for author File: Comments.pdf
Author Response
28-01-2025
Tittle: Response to Reviewers paper From Waste to Energy: Cooking Oil Recycling for Biodiesel in Barranquilla, Colombia
Dear Reviewer
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related as follow:
Comment |
Answer |
Line 56. Please clarify which catalyst was used to achieve the reported optimal oil-to-catalyst ratio of 1:12. Is this in reference to NaOH, KOH, or another type? Including a specific reference would strengthen the statement.
|
The catalyst used is NaOH. It was added on the paper. |
Line 98. Please reconsider whether rojecting data as far as the year 2100 is appropriate and methodologically justified. |
The information was corrected and validated. The Report – “Economía circular e innovación tecnológica en residuos sólidos Oportunidades en América Latina” from Banco de Desarrollo de America Latina supported the information. You can check i ton results section. |
Line 100. Please consider presenting the described data in a table or chart to allow for easier comparison of waste generation trends across regions (e.g., Sub-Saharan Africa, Europe and Central Asia, Latin America). A visual representation would enhance clarity and comprehension. |
The reference does not include all the information about waste generation trends. We also searched about UCO, but it is not completely found by country. However, there is information that you can find in our world in data, but it gets out of paper coverage. For that reason, we preferred not to include it. However, your comment is real representative and this information if is compiled is a great contribution in journal such as data-in-brief. See figure 1 as an example. |
Lines 121 122. Please clarify why the 1% acid value is used as the threshold for equiring pre-esterification. This value should be justified with a reference or supported by experimental reasoning. Without context, the threshold seems arbitrary. |
The information is referenced on the paper. The number is [19] and it support the listed information between 1 – 13. The information is based on:
[19] Tapanwong, M.; Punsuvon, V. Production of Ethyl Ester Biodiesel from Used Cooking Oil with Ethanol and Its Quick Glycerol-Biodiesel Layer Separation Using Pure Glycerol. International Journal of GEOMATE 2019, 17, 109–114, doi:10.21660/2019.61.4808. |
Line 127. You mention NaOH as the recommended catalyst, but it would be helpful to cite a specific reference or study that supports this choice as optimal. This strengthens the methodological basis of your recommendation. |
In a prior comment it was supported the catalyst as the NaOH based on reference listed as number [6]. However, the information is listed on reference [19] remining that listed information between 1 – 13 is supported with this reference. |
Lines 137 139. Please explain why a 1:3 water-to-biodiesel ratio is used and why neutral pH is the target. This step is likely intended to remove soap, excess catalyst, and methanol including a short explanation would enhance clarity and demonstrate process understanding. |
This step is essential to ensure the purification of biodiesel after the transesterification production process. The washing is necessary because, during transesterification (which converts oils such as used cooking oil, UCO, into biodiesel), several impurities remain, including residual catalysts (such as sodium or potassium hydroxide), soaps, free glycerol, unreacted alcohol, and other byproducts. Washing with distilled water removes these impurities, particularly residual catalysts and soaps, which could otherwise compromise the quality of the biodiesel. The procedure involves using distilled water at a ratio of one-third the volume of the biodiesel. The mixture is stirred thoroughly and then allowed to settle by decantation, enabling the water to carry the impurities to the bottom. This process is repeated until the pH of the wash water approaches neutral (around pH 7), indicating that the biodiesel is free of remaining contaminants.
The information follows the recommendation of reference 19. And also supported based on ASTM D6751 – 2020. |
Lines 144 148. Table 1 provides an informative overview of reaction efficiencies, but the criteria for selecting the included studies are not explained. Please indicate how the references were chosen and whether any statistical or comparative analysis was performed on these values. |
The sentence was adapted as follows to accomplish your recommendation: “To demonstrate the success of biodiesel production, the review process considered results published between 2019 and 2024. Table 1 presents the stoichiometric reaction yields achieved in biodiesel production from used cooking oil (UCO) using the trans-esterification method, based on data from 32 articles identified through the proposed search strategy. The results show that, in previous studies, the reaction yields were no lower than 80%, with more than half of the papers reporting yields above 93%.” |
Lines 154 158. Please consider adding standard deviations or confidence intervals for the biodiesel quality parameters listed in Table 2. This would provide a better understanding of data variability and support the reliability of the measurements. |
On table 2 is listed the value. After a revised procedure with laboratory, we do not experience standard deviations. They also are not included on Standard listed on table 2. |
Line 228. Please indicate which country's regulations are being referenced here. Since the study is based in Colombia, it would be appropriate to mention the specific legal framework or official guidelines that apply to household UCO disposal. |
The regulation was updated. The reference is the resolution 0316 – 2018. |
Lines 230 231. The statement is too general. Please refer to the specific Colombian legal framework that defines the role and responsibilities of a UCO manager. Including a citation to the relevant regulation would add clarity and strengthen the legal context of the manuscript. |
The information has been added based on Circular economy strategy and Resolution 0316-2018 |
Line 236. Please specify the types of agro-industrial residues considered relevant for second generation biodiesel production. Providing examples such as animal fats, slaughterhouse waste, food processing residues, or wastewater treatment by-products would improve clarity and technical completeness. |
The information was supported as follows: Second-generation biodiesel refers to fuel produced from non-food-based raw materials, particularly agro-industrial residues and high-biomass energy crops. Among the most relevant agro-industrial residues are animal fats derived from meat processing industries (such as tallow, poultry fat, and slaughterhouse by-products), waste from food processing activities (including used cooking oil, spent bleaching earth, and fruit or vegetable pulp), and lipid-rich waste from municipal and industrial wastewater treatment facilities. The use of these residues not only diverts organic waste from landfills and wastewater systems but also mitigates environmental impacts associated with improper disposal. Furthermore, second-generation biodiesel production reduces reliance on edible feedstocks, promoting a more sustainable and circular economic approach for urban and rural waste streams alike |
Line 406. The case study section would benefit from significant expansion. Currently, it only provides basic data on UCO collection quantities and company participation. To enhance the scientific and practical value of this section, please consider including the following: A map or diagram illustrating the geographic distribution of UCO collection points and companies involved in Barranquilla and Atlántico. More detailed information about the logistics: frequency of collection, transport methods, types of containers used, and safety procedures. Insights into operational challenges faced by collectors or recyclers (e.g., infrastructure, regulatory barriers, public participation). Economic or environmental impact estimates, such as cost savings, emissions reductions, or energy recovered. Community engagement strategies, if applicable e.g., how households or businesses were encouraged to participate. Expanding this section would strengthen the manuscript by showing the real-world applicability and scalability of the proposed strategy. |
Unfortunately, addressing this request has delayed our response to your comments, as the participating companies in Colombia have reserved the right not to be explicitly mentioned. They have only authorized the disclosure of general information regarding the quantities collected, without linking it to specific collection routes or identifying individual companies. Nevertheless, the positive outcomes of this project may create an opportunity to collaborate with the regulatory authority in the future, with the aim of developing an officially authorized collection route and encouraging stakeholders to share more detailed logistics data in subsequent studies. |
Information supporting comment: “Line 100. Please consider presenting the described data in a table or chart to allow for easier comparison of waste generation trends across regions (e.g., Sub-Saharan Africa, Europe and Central Asia, Latin America). A visual representation would enhance clarity and comprehension.” It is important to highlight that information exist on data base sush as Our World in Data.
Figure 1. Waste reycling rate between 2010 to 2022
Source: ourworldindata.org
Sincerely,
JORGE IVÁN SILVA ORTEGA Ph.D. |
PRINCE TORRES Ph.D. UNIVERSIDAD SIMON BOLIVAR |
Author Response File: Author Response.pdf
Reviewer 2 Report (New Reviewer)
Comments and Suggestions for AuthorsThis manuscript summarized and analyzed the recent literatures of cooking oil recycling for Biodiesel, and presents a strategy developed for the management of UCO for its energetic use in the production of biodiesel. The paper structure is complete and reasonable. This research is meaningful.
- Introduction: the status of UCO waste amount generated and the managements of UCO in Barranquilla, Colombia should be introduced.
- In section 2.1, line 98, the “data between 2010 and 2100” is confusing, how to get the data in 2100 should be explained. Line100, the UCO data in Barranquilla should be provided.
- In section 2.2, the table 2 is too long, it can be classified and summarized by the biodiesel generation technique.
- In section 4.1, the Fig. 2 showed two layers and 15 indictors which effects the waste management. It would be better to give an index weight value to calculate for strategy evaluation.The Table 3 should be edited, such as: the phrase of “Circular National Strategy” is in two lines.
- It would be better to describe 4.2 of the manuscript in more detail. Such as: quantify the importance of each step of the process in 4.2 and give some examples.
- In section 4.3, line 322, what’s the meaning of silver in “silver strategy”. Since every step of the process is believed to be important, it would be better to be ranked according to the expert rating.
- In section 5, the Fig. 4 showed the UCO reception data, but no biodiesel data. It’s not good for the strategy evaluation, and it’s hard to optimize for the comprehensive strategy.
Author Response
28-04-2025
Tittle: Response to Reviewers paper From Waste to Energy: Cooking Oil Recycling for Biodiesel in Barranquilla, Colombia
Dear Reviewer
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related as follow:
Thank you very much for your positive and encouraging feedback. We sincerely appreciate your recognition of the structure, relevance, and contribution of our manuscript. Your kind words motivate our research group to continue advancing in the research and development of sustainable strategies for used cooking oil management and biodiesel production. We adapted your comments in the paper and the following considerations were taken based on your comments:
Comment 01: The status of UCO waste amount generated and the managements of UCO in Barranquilla, Colombia should be introduced.
Response 01: The national and district regulations were included and the information regarding UCO management, as supported by previous studies, is presented and discussed throughout the introduction and the document.
Comment 02: In section 2.1, line 98, the “data between 2010 and 2100” is confusing, how to get the data in 2100 should be explained. Line100, the UCO data in Barranquilla should be provided.
Response 02: the information was corrected and updated. The information goes between 2001 to 2010. It was a typing error. The UCO data in Barranquilla also was included on introduction.
Comment 03: In section 2.2, the table 2 is too long, it can be classified and summarized by the biodiesel generation technique.
Response 03: we considered the parameters considered in the research and strategy.
Comment 04: In section 4.1, the Fig. 2 showed two layers and 15 indictors which affect waste management. It would be better to give an index weight value to calculate for strategy evaluation.The Table 3 should be edited, such as: the phrase of “Circular National Strategy” is in two lines.
Response 04: at this moment the concept more than a quantitative model is a reference guide to improve on phases to integral waste management. Our research group is working on index with weight value to estimate and evaluate the process developed by UCO collectors. However, this will be worked on a different document. While, table 3 has been updated based on recommendations.
Comment 05: It would be better to describe 4.2 of the manuscript in more detail. Such as: quantify the importance of each step of the process in 4.2 and give some examples.
Response 05: thanks for your comment, but we followed the five steps listed as logistic, quality, disposal, storage and commercialization. All steps are a sequence and their development and verification impact on results.
Comment 06: In section 4.3, line 322, what’s the meaning of silver in “silver strategy”. Since every step of the process is believed to be important, it would be better to be ranked according to the expert rating.
Response 06: The 'Silver Strategy' was the internal name used by the research group. However, it was removed to make the strategy more generic and applicable to various regions, which aligns with the purpose of the paper. Thank you for your comment.
Comment 07: In section 5, the Fig. 4 showed the UCO reception data, but no biodiesel data. It’s not good for the strategy evaluation, and it’s hard to optimize for the comprehensive strategy.
Response 07: Figure 4 and the UCO reception data aim to demonstrate the potential volume and quantity of UCO available for biodiesel production. This information is crucial for highlighting the potential benefits of UCO collection in other cities or regions, based on relevant statutes and regulations, to obtain products such as biodiesel. Our focus is on exploring these potential uses.
Sincerely,
JORGE IVÁN SILVA ORTEGA Ph.D. |
PRINCE TORRES Ph.D. UNIVERSIDAD SIMON BOLIVAR |
Author Response File: Author Response.pdf
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
Review of the Article
Title: Strategy for the management of cooking oil waste for energy use in biodiesel production
Authors: Marylin Santander-Bossio, Jorge Silva-Ortega, Ruben Cantero-Rodelo, Juan Rivera-Alvarado, Christian Moreno-Rocha, Celene Milánes-Batista
Dear Authors,
I revised the manuscript “Strategy for the management of cooking oil waste for energy use in biodiesel production” submitted to the Sustainability Journal. The authors address a highly relevant and timely issue of waste management, particularly focusing on the utilization of used cooking oil (UCO) as a sustainable feedstock for biodiesel production. This study provides valuable insights into the development of circular economy strategies in developing countries, specifically in the context of Colombia. The paper presents an innovative approach to waste valorization and has significant potential to contribute to both environmental protection and energy production. The paper is interesting. However, I have some concerns, which need to be addressed.
1. Scientific Evaluation of the Article
1.1. Originality and Importance of the Study
- The article addresses a significant and timely issue of managing used cooking oil (UCO) waste and its utilization for biodiesel production. The study aligns with contemporary trends in circular economy and sustainable development.
- Its originality lies in proposing a strategy tailored to a specific region (Colombia), which could serve as inspiration for other developing countries.
1.2. Consistency of Purpose and Scope
- The purpose of the study is clearly defined: to develop a strategy for UCO waste management aimed at biodiesel production.
- The scope is well-delineated, encompassing technological, economic, and environmental aspects.
2. Methodology Assessment
2.1. Description of Research Methods
- The article provides a detailed description of the biodiesel production process from UCO, including transesterification and quality analysis. The processes are clearly explained, enabling reproducibility.
- The use of literature to evaluate biodiesel quality parameters is appropriate, but more detailed information on sampling and data analysis methods is needed.
Suggestion: Expand the methodology section by including precise criteria for sample selection and data analysis techniques.
2.2. Selection of Technological Parameters
- Parameters such as alcohol-to-oil ratio and reaction temperature are aligned with industrial standards.
- Diagrams illustrating processes (e.g., UCO collection, purification, and transesterification) are helpful but could be enriched with numerical data.
Suggestion: Provide a detailed justification for the selected process parameters, based on literature and experimental data.
3. Results and Analysis
3.1. Presentation of Results
- Quantitative results on UCO collection efficiency and biodiesel yield are well presented.
- The analysis of transesterification efficiency (93.67%) is consistent with the literature and highlights the potential of the technology.
Suggestion: Include statistical analysis of the results to strengthen their reliability.
3.2. Discussion of Results
- The discussion relates findings to the literature, but there is a lack of deeper comparisons with previous studies.
- The article identifies barriers to strategy implementation, which is a strong point.
Suggestion: Consider a more detailed discussion of the barriers (e.g., financial and social) and possible solutions.
4. Language and Style
- The language used in the article is technical yet accessible for specialists in the field. However, some sentences are overly complex, which may hinder understanding.
- The style complies with MDPI requirements, including the use of proper citation norms.
5. Conclusions and Recommendations
5.1. Summary of Conclusions
- The conclusions align with the results and emphasize the potential of UCO for large-scale biodiesel production.
- The study integrates the circular economy principles, which is a notable strength.
Suggestion: Expand the conclusions section with specific recommendations for implementing the strategy in other regions.
5.2. Future Research Directions
- The article suggests the need for further comparative studies between first-generation and second-generation biodiesel.
Suggestion: Add more details on future research directions, such as cost analysis of implementation.
6. Overall Evaluation
The article presents valuable research with substantial practical and scientific potential. However, improving the methodology detail, expanding the discussion section, and enhancing result interpretation through statistical analysis would significantly strengthen the manuscript.
Recommendation: Minor Revisions – the article requires minor corrections to fully comply with MDPI standards and enhance its scientific quality.
Author Response
14-01-2025
Tittle: Response to Reviewers
Dear Reviewer
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related to:
- The authors address a highly relevant and timely issue of waste management, particularly focusing on the utilization of used cooking oil (UCO) as a sustainable feedstock for biodiesel production.
- This study provides valuable insights into the development of circular economy strategies in developing countries, specifically in Colombia.
- The paper presents an innovative approach to waste valorization and has significant potential to contribute to both environmental.
These comments motives us to answers and continue with the process. The paper considers the following recommendations:
- We expanded the methodology section, including precise criteria for sample selection and data analysis techniques.
- We proposed a detailed justification for the selected process parameters, based on literature and experimental data.
- We supported the statistical analysis of the results to strengthen their reliability based on the total sample considered. We highlighted that the focus was on the total strategy and the set of elements and phases that must be managing UCO.
- The paper considered a more detailed discussion of the barriers.
- Researchers expanded the conclusions with specific recommendations for implementing the strategy in other regions.
- The conclusions included the paper’s future trends.
Best,
Jorge Silva Ortega
UNIVERSIDAD DE LA COSTA
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe article is devoted to the development of a strategy for the management of waste cooking oils (UCO) for their use in the production of second-generation biodiesel. The main focus is on the development of a comprehensive strategy that includes the collection, analysis, storage and recycling of UCO, as well as the management of this process taking into account social and environmental responsibility. The authors consider the work in the context of the circular economy. Overall, the work is positive, but I do not understand the scientific contribution to the work. The authors showed a strategy in the work, but the strategy is a practical aspect of the work. I would like to see a contribution to science. Also, the article has the status of "Article", but in this form the article is more like a "review" section. In my opinion, the work has two main conclusions: the use of the most efficient process for converting fats into biodiesel with an efficiency of up to 98% and the creation of an infrastructure for the collection and recycling of UCO helps to reduce environmental risks, such as eutrophication of water bodies and soil degradation. But this is not a scientific contribution.
Critical comments. 1. The paper does not sufficiently cover economic aspects related to the long-term sustainability of the strategy, such as financial costs of infrastructure and expected profitability.
2. The literature review covers a broad range of data, but could have provided more detail on examples of successful implementation of similar strategies in other regions.
3. It is recommended to conduct a sensitivity analysis of key variables (e.g. UCO collection and processing costs) to improve the applicability of the strategy.
Questions
1. What is the contribution to science? State this very clearly in your paper.
2. Line 36. The text “environmental and social problems [1].” It is recommended to add a reference to the work doi.org/10.1038/s41598-023-41962-0
3. Line 51. "based on trials, is 1:12" — more correctly "based on trials is 1:12".
4. Line 117. A comma is missing before "and an oil-alcohol ratio of 12:1".
Author Response
14-01-2025
Tittle: Response to Reviewers
Dear Reviewers
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related to the relevance of the manuscript. Your comments were valuable during our review process and identify your contribution.
Critical comments:
- The paper does not sufficiently cover economic aspects related to the long-term sustainability of the strategy, such as financial costs of infrastructure and expected profitability.
- The literature review covers a broad range of data but could have provided more detail on examples of successful implementation of similar strategies in other regions.
- It is recommended to conduct a sensitivity analysis of key variables (e.g. UCO collection and processing costs) to improve the applicability of the strategy.
Response to critical comments: This paper emerged from three years of research aimed at verifying the implemented methodology. Economic aspects related to the study remain under investigation and are an integral part of ongoing research efforts. The literature review focuses on reaction performance, demonstrating the viability of UCO as a feedstock for biodiesel production. Your comments and suggestions will be considered to improve future iterations of this work. A forthcoming paper will incorporate economic analyses, sensitivity studies of key variables, and insights from successful experiences with similar strategies.
The response to your questions, they have been totally answered in the paper and highlighted in red color.
- The contribution has been stated clearly in the paper.
- The reference suggested has been added in Line 36 (doi.org/10.1038/s41598-023-41962-0).
- An error in Line 51was corrected.
- An error in Line 117 was corrected.
Best,
Jorge Silva Ortega
UNIVERSIDAD DE LA COSTA
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe manuscript idea is relevant. However, the manuscript is written in a somewhat dismissive manner. It needs to be reviewed and corrected. Then it could be resubmitted.
The title of the article is "A Strategy for the Management of Waste Cooking Oil for Energy Use in Biodiesel Production", however I do not see that a strategy has been created, except for its guidelines.
I suggest specifying the title, as the Study case only covers Barranquilla and the Atlántico Department.
It would be useful to give specified information of the amount of waste vegetable oil in the introduction, not just “Approximately 15% of clean vegetable oil becomes waste after use”.
Section 2.2 describes “The stages of the biodiesel production process from UCO are as follows”. However, no literature sources are specified.
Table 2 specifies reaction performance, what is “Reaction performance”?
In manuscript there are 2 Tables 2, however Table 1 and Table 2 are mentioned in the text.
If figures and tables are provided, they must be mentioned and described in the text.
There is no discussion after Table 2 (Efficiency of the reactions reached in previous work) and Figure 2.
In Chapter 5, the text mentions Figure 3, but provides figure 4. In my opinion, figure 5 is unnecessary.
Line 394 says "each company", the companies should be listed.
Author Response
14-01-2025
Tittle: Response to Reviewers
Dear Reviewers
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related to the relevance of the manuscript. Your comments were really valuable during our review process and identify your contribution.
Comment 1: The title of the article is "A Strategy for the Management of Waste Cooking Oil for Energy Use in Biodiesel Production", however I do not see that a strategy has been created, except for its guidelines.
Response 1: we understand your point of view but the strategy are those guidelines integrated by a process and experiences learned in order to be implemented in other regions with similar situations.
Comment 2: I suggest specifying the title, as the Study case only covers Barranquilla and the Atlántico Department.
Response 2: we do not want to limit the paper contribution only to a case study. The real relevance is related with the strategy (figure 2) and framework which is supported with a solid literature review.
Comment 3: It would be useful to give specified information of the amount of waste vegetable oil in the introduction, not just “Approximately 15% of clean vegetable oil becomes waste after use”.
Response 3: We used references to support information. The UCO as waste change rappidly and information is not always reported.
Commet 4: Section 2.2 describes “The stages of the biodiesel production process from UCO are as follows”. However, no literature sources are specified.
Response 4: The reference has been added after colon.
Commet 5: Table 2 specifies reaction performance, what is “Reaction performance”?
Response 5: The table 2 name has been updated.
Commet 6: In manuscript there are 2 Tables 2, however Table 1 and Table 2 are mentioned in the text.
Response 6: information has been updated.
Commet 7: If figures and tables are provided, they must be mentioned and described in the text.
Response 7: All figure has been listed and mentioned in the text.
Comment 8: There is no discussion after Table 2 (Efficiency of the reactions reached in previous work) and Figure 2.
Response 8: Related to table 2 and figure 2 the information has been updated.
Comment 9: In Chapter 5, the text mentions Figure 3, but provides figure 4. In my opinion, figure 5 is unnecessary.
Response 9: information has been updated.
Comment 10: Line 394 says "each company", the companies should be listed.
Response 10: To maintain confidentiality, the paper withholds company names.
Best,
Jorge Silva Ortega
UNIVERSIDAD DE LA COSTA
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for Authorsno comments
Author Response
30-01-2025
Tittle: Response to Reviewers
Dear Reviewer
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related to the relevance of the manuscript. Your comments were valuable during our review process and identify with your contribution. We appreciate your time and comments.
Best,
Jorge Silva Ortega
UNIVERSIDAD DE LA COSTA
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe quality of the manuscript has improved, however further improvements are needed.
The abbreviation UCO needs to be explained in the Abstract.
Table 2 needs to be improved, as not all standard indicators are included.
In English, it should be written, for example: 0.8, not 0,8. Correct everywhere in a manuscript.
The previous note was “I suggest specifying the title, as the Study case only covers Barranquilla and the Atlántico Department. Response 2: we do not want to limit the paper contribution only to a case study. The real relevance is related with the strategy (figure 2) and framework which is supported with a solid literature review. However, I disagree with the answer, as in developing the strategy guidelines a narrow region was analyzed. In addition, in concluding that “ a pilot project showed that in the department produces 963,070.95 kg/year of waste cooking oil and this could produce 902,108.56 kg/year of biodiesel.” it is necessary to mention the year, because the authors themselves, in response to my previous notes, mentioned that “ UCO as waste change rapidly…”
Author Response
06-02-2025
Tittle: Response to Reviewers
Dear Reviewers
We have revised your comments and recommendations to enhance the paper contribution. Thanks for your comments related to the relevance of the manuscript. Your comments were valuable during our review process and identify your contribution.
Comment No. 1. The quality of the manuscript has improved, however further improvements are needed.
Response No. 1. Thanks for your recommendation. We have already checked the comments and updated quality on the document.
Comment No. 2. The abbreviation UCO needs to be explained in the Abstract.
Response No. 2. The comment has been updated.
Comment No. 3. Table 2 needs to be improved, as not all standard indicators are included.
Response No. 3. The table 2 has been improved.
Comment No. 4. In English, it should be written, for example: 0.8, not 0,8. Correct everywhere in a manuscript.
Response No. 4. Corrected
Comment No. 5. The previous note was “I suggest specifying the title, as the Study case only covers Barranquilla and the Atlántico Department. Response 2: we do not want to limit the paper contribution only to a case study. The real relevance is related with the strategy (figure 2) and framework which is supported with a solid literature review. However, I disagree with the answer, as in developing the strategy guidelines a narrow region was analyzed. In addition, in concluding that “ a pilot project showed that in the department produces 963,070.95 kg/year of waste cooking oil and this could produce 902,108.56 kg/year of biodiesel.” it is necessary to mention the year, because the authors themselves, in response to my previous notes, mentioned that “ UCO as waste change rapidly…”
Response No. 5. The tittle has been updated according with your recomendation.
Best,
Jorge Silva Ortega
UNIVERSIDAD DE LA COSTA
Author Response File: Author Response.pdf