Production of High-Value Green Chemicals via Catalytic Fast Pyrolysis of Eucalyptus urograndis Forest Residues
, Tiago Guimarães, Marcelo M. da Costa, Larissa S. Silva, Verônica O. de P. Barbosa, Stéphani Caroline de L. Arêdes, Krisnna S. Alves and Ana Márcia M. L. Carvalho
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn this work, the catalytic fast pyrolysis of Eucalyptus urograndis canopy was carried out using a pyrolyzer coupled to gas chromatography/mass spectrometry (Py-GC/MS) at different temperatures and in the presence and absence of catalysts. The feasibility of using the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products was evaluated, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI).
Introduction part:
1. Current status of research on the production of high value-added chemical products from biomass through catalytic fast pyrolysis, what are the advantages and the main problems that need to be solved?
2. The key issue for the catalytic fast pyrolysis is to select the right catalysts for the desired type of reaction, what types of catalysts are commonly used? How selective are catalysts for pyrolysis products?
Results and Discussion part:
3. To obtain the results of the chemical composition of the Eucalyptus urograndis canopy, the authors did elemental analysis, so why did not choose Chemical Composition analysis?
4. The authors did not make a proper presentation of Table 1, especially the analysis of metal content.
5. The catalyst would act by influencing the decomposition of the Eucalyptus urograndis canopy, altering the distribution and content of chemical compounds, however, the production of Hydrogen, Furfural, and Levoglucosan were low, what was the level of this rate compared to other similar studies?
6. The authors briefly analyze the distribution and content of pyrolysis products after using catalysts copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI), and how the pyrolysis products can be further separated and purified in order to obtain high-value-added chemical products?
7. L276-278, according to the literature, on an industrial scale, the pyrolysis of lignocellulosic biomass yields a bio-oil with approximately 60% efficiency. In addition, the yield of char is in the range of 30 - 35%. In your research, the Eucalyptus urograndis canopy using CuO as a catalyst, what percentage of each is bio-oil, char and gas?
Comments on the Quality of English LanguageIn this work, the catalytic fast pyrolysis of Eucalyptus urograndis canopy was carried out using a pyrolyzer coupled to gas chromatography/mass spectrometry (Py-GC/MS) at different temperatures and in the presence and absence of catalysts. The feasibility of using the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products was evaluated, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI).
Introduction part:
1. Current status of research on the production of high value-added chemical products from biomass through catalytic fast pyrolysis, what are the advantages and the main problems that need to be solved?
2. The key issue for the catalytic fast pyrolysis is to select the right catalysts for the desired type of reaction, what types of catalysts are commonly used? How selective are catalysts for pyrolysis products?
Results and Discussion part:
3. To obtain the results of the chemical composition of the Eucalyptus urograndis canopy, the authors did elemental analysis, so why did not choose Chemical Composition analysis?
4. The authors did not make a proper presentation of Table 1, especially the analysis of metal content.
5. The catalyst would act by influencing the decomposition of the Eucalyptus urograndis canopy, altering the distribution and content of chemical compounds, however, the production of Hydrogen, Furfural, and Levoglucosan were low, what was the level of this rate compared to other similar studies?
6. The authors briefly analyze the distribution and content of pyrolysis products after using catalysts copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI), and how the pyrolysis products can be further separated and purified in order to obtain high-value-added chemical products?
7. L276-278, according to the literature, on an industrial scale, the pyrolysis of lignocellulosic biomass yields a bio-oil with approximately 60% efficiency. In addition, the yield of char is in the range of 30 - 35%. In your research, the Eucalyptus urograndis canopy using CuO as a catalyst, what percentage of each is bio-oil, char and gas?
Author Response
Reviewer 1
Comments and Suggestions for Authors
In this work, the catalytic fast pyrolysis of Eucalyptus urograndis canopy was carried out using a pyrolyzer coupled to gas chromatography/mass spectrometry (Py-GC/MS) at different temperatures and in the presence and absence of catalysts. The feasibility of using the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products was evaluated, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI).
Introduction part:
- Current status of research on the production of high value-added chemical products from biomass through catalytic fast pyrolysis, what are the advantages and the main problems that need to be solved?
Answer: We acknowledge the reviewer's concerns, and This paragraph was added for better understanding.
“Currently, the production of high-value-added chemical products from forest biomass through catalytic fast pyrolysis is focused on improving the efficiency and selectivity of catalysts [15], as well as their stability under operational conditions [16]. Issues related to scalability for large-scale production and cost reduction are also being addressed, aiming at the commercial viability of the technology [17]. Furthermore, there is an ongoing effort to assess the total environmental impact of the process, considering not only the sustainability of the raw material, but also issues such as the use of natural resources and greenhouse gas emissions throughout the entire process [18].”
- The key issue for the catalytic fast pyrolysis is to select the right catalysts for the desired type of reaction, what types of catalysts are commonly used? How selective are catalysts for pyrolysis products?
Answer: We acknowledge the reviewer's concerns, and several catalysts are used for pyrolysis processes, and the choice of which catalyst to use is related to its application, availability and cost. That is why the use of catalysts based on metals such as copper, iron and titanium are more commonly used.
Results and Discussion part:
- To obtain the results of the chemical composition of the Eucalyptus urograndis canopy, the authors did elemental analysis, so why did not choose Chemical Composition analysis?
Answer: We acknowledge the reviewer's concerns, and the choice between elemental analysis and chemical composition analysis depends on the research objectives and the information desired. In this case, elemental analysis provides information about the elements present in a sample, such as carbon, hydrogen, oxygen, nitrogen, sulfur. In the case of characterizing the crown of Eucalyptus urograndis, we opted for elemental analysis because the main interest was determining the chemical elements present in the sample.
- The authors did not make a proper presentation of Table 1, especially the analysis of metal content.
Answer: We acknowledge the reviewer's concerns, and a more adequate presentation of Table 1 has been added, mainly to discuss the analysis of metal content. As can be seen below:
“The results found for the metals present in the Eucalyptus urograndis canopy are comparable to those described in the literature with more expressive results for K, Na and Mg [29]. Félix et. al. (2017) characterized samples from eucalyptus biomass for use in pyrolysis processes and encounters the presence of metals such as K, Ca, Mn, Mg and Si [30]. The values of inorganic and insoluble in HCl (6M) are also within the expected, according to the literature [27].”
- The catalyst would act by influencing the decomposition of the Eucalyptus urograndis canopy, altering the distribution and content of chemical compounds, however, the production of Hydrogen, Furfural, and Levoglucosan were low, what was the level of this rate compared to other similar studies?
Answer: We acknowledge the reviewer's concerns, and the catalyst application rate was 1% m/m. Due to the low levels production of hydrogen, furfural, and levoglucosan, new studies will be carried out using different proportions of catalysts.
- The authors briefly analyze the distribution and content of pyrolysis products after using catalysts copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI), and how the pyrolysis products can be further separated and purified in order to obtain high-value-added chemical products?
Answer: We acknowledge the reviewer's concerns, and the separation and purification of pyrolysis products, such as hydrogen, furfural, acetic acid and levoglucosan, can be carried out using different techniques. for better understanding, a paragraph was added in the conclusion as a suggestion for future work.
“Studies are still necessary to separate and purify the chemical compounds produced. For hydrogen, methods such as membrane separation, absorption/desorption can be used, taking advantage of its permeability and condensability properties. Furfural can be purified by distillation, liquid-liquid extraction and crystallization, while acetic acid can be separated by distillation, extraction and crystallization. Levoglucosan, in turn, could be purified by chromatography, precipitation and/or liquid-liquid extraction, aiming to achieve high levels of purity and yield of high-value-added chemicals.”
- L276-278, according to the literature, on an industrial scale, the pyrolysis of lignocellulosic biomass yields a bio-oil with approximately 60% efficiency. In addition, the yield of char is in the range of 30 - 35%. In your research, the Eucalyptus urograndis canopy using CuO as a catalyst, what percentage of each is bio-oil, char and gas?
Answer: We acknowledge the reviewer's concerns, but in the Py-GC/MS process it is not possible to accurately determine the percentages of bio-oil, biochar and syngas produced, so the techno-economic analysis was carried out using values found in the literature for similar processes.
Reviewer 2 Report
Comments and Suggestions for Authors - The manuscript deals with the feasibility of using the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI). - The introduction is sufficient and represents the aim of the study comparing it with previous ones, - Materials and methods section provides a clear and detailed description of the experimental procedures for production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues - The results section efficiently presents the production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues- The discussion section should be expanded to display the results and compare the obtained results with previous ones. - The conclusion briefly summarizes the key findings of the study, emphasizing that the catalytic fast pyrolysis of the Eucalyptus urograndis canopy can be a promising route for the production of bio-oil and high-value-added chemical compounds. - The Tables and Figures are clear
- Page 1 lines 17 and 18: carbon, hydrogen, and oxygen should start with small letters
- Page 1 lines 19 and 20: acetic acid, hydrogen, furfural, and levoglucosan should start with small letters
- Page 3 line 86: Eucalyptus urograndis should be italic
- Page 5 lines 159 and 161: acetic acid, levoglucosan and furfural should start with small letters
- Page 6 line162: hydrogen should start with small letter
- Page 6 line176: hydrogen, furfural, and levoglucosan should start with small letters
- Page 8 line 235: hydrogen and levoglucosan should start with small letters
- Page 9 line243: hydrogen should start with small letter
- Page 9 lines 348: acetic acid, hydrogen, and levoglucosan should start with small letters
- Page 9 line 251: Eucalyptus urograndis should be italic
- Page 10 line257: hydrogen should start with small letter
- Page 10 line262 and 263: acetic acid should start with small letter
- Page 10 lines 271 and 272: furfural and levoglucosan should start with small letters
- Page 10 lines 278: acetic acid should start with small letter
- Page 10 lines 281 and 282: hydrogen, furfural, and levoglucosan should start with small letters
- Page 11 line 302: carbon, hydrogen, and oxygen should start with small letters
- The manuscript could be accepted after minor revision of the above comments
Author Response
Reviewer 2
Comments and Suggestions for Authors
- The manuscript deals with the feasibility of using the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI). - The introduction is sufficient and represents the aim of the study comparing it with previous ones, - Materials and methods section provides a clear and detailed description of the experimental procedures for production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues - The results section efficiently presents the production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues
- The discussion section should be expanded to display the results and compare the obtained results with previous ones. - The conclusion briefly summarizes the key findings of the study, emphasizing that the catalytic fast pyrolysis of the Eucalyptus urograndis canopy can be a promising route for the production of bio-oil and high-value-added chemical compounds. - The Tables and Figures are clear
Page 1 lines 17 and 18: carbon, hydrogen, and oxygen should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 1 lines 19 and 20: acetic acid, hydrogen, furfural, and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 3 line 86: Eucalyptus urograndis should be italic.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 5 lines 159 and 161: acetic acid, levoglucosan and furfural should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 6 line 162: hydrogen should start with small letter.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 6 line 176: hydrogen, furfural, and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 8 line 235: hydrogen and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 9 line 243: hydrogen should start with small letter.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 9 lines 248: acetic acid, hydrogen, and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 9 line 251: Eucalyptus urograndis should be italic.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 10 line 257: hydrogen should start with small letter.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 10 line 262 and 263: acetic acid should start with small letter.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 10 lines 271 and 272: furfural and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 10 lines 278: acetic acid should start with small letter.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 10 lines 281 and 282: hydrogen, furfural, and levoglucosan should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
Page 11 line 302: carbon, hydrogen, and oxygen should start with small letters.
Answer: We acknowledge the reviewer's concerns, and the changes were made.
The manuscript could be accepted after minor revision of the above comments.
Answer: We acknowledge the reviewer's concerns, thank you for your time and corrections and are happy to announce that all requested changes have been made.
Reviewer 3 Report
Comments and Suggestions for AuthorsThis manuscript discuss about the Production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues.
An interesting knowledge has been reported. However the following comments should be addressed.
Comments
Author must highlight the novelty of Research question very clearly in the introduction which is not mentioned.
The introduction part should be further improved. The importance of pyrolysis in economical and biotechnological form should be mentioned
Enhance the quality of graphical abstract
Authors should discuss about how does the concentration of biomass of Eucalyptus urograndis affect the preparation and catalysis process
Authors should compare and discuss about copper oxide (CuO), titanium 71
dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI) on catalysis process
Comments on the Quality of English LanguageMinor editing of English language required. There are few typological errors are present that should be revised carefully
Author Response
Reviewer 3
Comments and Suggestions for Authors
This manuscript discusses about the Production of high-value green chemicals via catalytic fast pyrolysis of Eucalyptus urograndis forest residues. An interesting knowledge has been reported. However, the following comments should be addressed.
Author must highlight the novelty of Research question very clearly in the introduction which is not mentioned.
Answer: We acknowledge the reviewer's concerns, and the text has been added for better understanding:
“Currently, several studies have been conducted to produce high-quality bio-oil via rapid catalytic pyrolysis of biomass, where the key issue for the process is to select the right catalysts for the desired type of reaction [19].
In this study, the novelty will be the use the residue from the Eucalyptus urograndis canopy for the production of hydrogen and high-value-added chemical products was evaluated, through catalytic fast pyrolysis, using catalysts such as: copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI).”
The introduction part should be further improved. The importance of pyrolysis in economical and biotechnological form should be mentioned
Answer: We acknowledge the reviewer's concerns, and the text has been added for better understanding:
“Pyrolysis plays a crucial role both in the economic and biotechnological spheres, standing out as a versatile and promising technique [10]. Economically, pyrolysis enables the efficient conversion of biomass, agricultural residues, and plastics into a variety of valuable products such as biofuels, chemicals, and carbonaceous materials [11]. This approach not only reduces the dependence on fossil resources but also contributes to mitigating greenhouse gas emissions [12].
Additionally, in the biotechnological realm, pyrolysis offers significant opportunities for the production of biofertilizers, biochar, and other value-added products, promoting agricultural sustainability and efficient organic waste management [13]. Thus, the application of pyrolysis plays a fundamental role in transitioning towards a more circular and sustainable economy, driving both technological innovation and environmental conservation [14].”
Enhance the quality of graphical abstract
Answer: We acknowledge the reviewer's concerns, and the graphical abstract quality was provided. The image represents the process of converting Eucalyptus urograndis biomass into bio-oil, biochar and syngas using the Py-GC/MS technique. The main points observed:
- Eucalyptus urograndis biomass - The photo of Eucalyptus urograndis trees represents the source of biomass.
- The map of Brazil highlights the geographic location.
- Conversion Process: The py-GC-MS equipment is central to the process. with a temperature of 300°C and a time of 6 seconds being indicated.
- The Resulting products with their respective market prices:
- Biochar: Price of 0.40 USD/kg.
- Bio-oil (components):
- Furfural: 13.00 USD/kg
- Levoglucosan: 1.33 USD/kg
- Acetic acid: 3.40 USD/kg
- Syngas (hydrogen): 6.00 USD/kg
- Total Balance: 466.10 USD/ton.
Authors should discuss about how does the concentration of biomass of Eucalyptus urograndis affect the preparation and catalysis process
Answer: We acknowledge the reviewer's concerns, and the text has been added for better understanding:
“As the concentration of biomass and catalysts affect the results in the reaction, the mass used was standardized to 0.100 ± 0.005 mg with 1% (m/m) of catalyst, in catalytic Py-GC/MS experiments.”
Authors should compare and discuss about copper oxide (CuO), titanium dioxide (TiO₂), cobalt ferrite (CoFe₂O₄), and iron nanoparticles (nZVI) on catalysis process.
Answer: We acknowledge the reviewer's concerns, and the text has been added for better understanding:
“The results of this study indicate that the catalytic fast pyrolysis of canopy Eucalyptus urograndis has significant potential for the production of chemical products with high added value. As observed in Figure 6, the hydrogen production varies according to the catalyst used and the temperature of the pyrolysis process, and the CuO was identified as the most effective catalyst for the process, demonstrating the best results under operating conditions when compared to other catalysts, such as titanium diox-ide (TiO₂), cobalt ferrite (CoFe₂O₄) and iron nanoparticles (nZVI ).”
Comments on the Quality of English Language
Minor editing of English language required. There are few typological errors are present that should be revised carefully.
Answer: We acknowledge the reviewer's concerns, and the manuscript was carefully reviewed.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe paper is acceptable.
Comments on the Quality of English LanguageThe paper can be acceptable.
Reviewer 3 Report
Comments and Suggestions for AuthorsAccept
