FTIR Analysis of the Functional Group Composition of Coal Tar Residue Extracts and Extractive Residues
Round 1
Reviewer 1 Report
Dear Authors,
You can find some remarks through the text.
Best Regards
Comments for author File: 
Comments.pdf
Author Response
Point 1: insert space.
Response 1: All sections requiring spaces have been added.
Point 2: I can suggest full names of these methods for the first mention.
Response 2: The first occurrence of the abbreviation has been changed to the full name.
Point 3: what is the origin of the samples?
Response 3: Coal tar residue came from the Yulin Lanchar plant.
Point 4: please, explain what these abbreviations are in footnote, or elsewhere .
Response 4: Where Mad is air dry basis moisture, Ad is dry basis ash, Vdaf is dry ash-free basis volatile fraction and FCad air dry basis fixed carbon.
Point 5: The text in the image needs to be in English.
Response 5: All changes have been made.
Point 6: Maybe you can insert here sentence or two of the practical and ecological use of these experiments,mainly concerning the PAHs, for better readersunderstanding.
Response 6: Additions have been made.
Reviewer 2 Report
Dear authors,
In this paper, FTIR analysis of the functional group composition of coal tar residue extracts and extractive residues, Manuscript ID: applsci-228327, single-stage extraction experiments with acetone, CS2, and acetone/CS2 as solvents were carried out on tar residues using ultrasonic-assisted extraction at room temperature. The extracts and extractive residues were analyzed by FT-IR detection and segmented peak fitting analysis in order to obtain the structural characteristics of the soluble organic components in the tar residues. The results showed that acetone and CS2 solvents could dissolve more aromatic structures containing fatty side chains, while the mixed solvents could extract more phenolic substances.
The results of peak splitting fit for extracts into the different intervals in great detail were presented by the authors. Also, an analysis of the structural parameters of the three extracts and of tar residues and extractives was done. The manuscript is very detailed in terms of IR analysis. The analysis of the composition of the extraction results provides a reference basis for the separation and purification technology of coal tar residue.
I have a remark about the introduction, which is rather short and does not give a particular overview of the state of the art of this research in the world. In this sense, the list of references is also insufficient. It needs to be expanded.
Sincerely
Author Response
Point 1:Dear authors,
In this paper, FTIR analysis of the functional group composition of coal tar residue extracts and extractive residues, Manuscript ID: applsci-228327, single-stage extraction experiments with acetone, CS2. and acetone/CS2 as solvents were carried out on tar residues using uiltrasonic-assisted extraction at room temperature. The extracts and extractive residues were analyzed by FT-IR detection and segmented peak ftting analysis in order to obtain the structural Characteristics of the soluble organic components in the tar residues. The results showed that acetone and CS2 solvents could dissolve more aromatic structures containing fatty side chains,while the mixed solvents could extract more phenolic substances.
The results of peak splitting fit for extracts into the different intervals in great detail were presented by the authors. Also, an analysis of the structural parameters of the three extracts and of tar residues and extractives was done. The manuscript is very detailed in terms of IR analysis.The analysis of the composition of the extraction results provides a reference basis for the separation and purfication technology of coal tar residue.
I have a remark about the introduction, which is rather short and does not give a particular overview of the state of the art of this research in the world. In this sense, the list of references is also insuficient. It needs to be expanded.
Response 1:Additions have been made to the introductory section.
