Arsenic, Iron, and Manganese Adsorption in Single and Trinary Heavy Metal Solution Systems by Bamboo-Derived Biochars

Round 1

Reviewer 1 Report

In this paper authors examined removal of As, Fe and Mn using bamboo biochar. The theme is very good, but certain shortcomings must be corrected.

1. In Introduction part it is necessary to point out the advantages of using biochar in relation to raw biomass as potential adsorbent material. Besides, summarize the findings of previous studies that use bamboo biochar as an adsorbent. In addition, highlight the scientific contribution of this study.

2. Provide more details about biochar preparation.

3. Please provide standard deviations for results.

4. Why a kinetic study wasn't done?

5. Complete part 3.2 in detail, with conclusions supporeted by literature.

6. General comment, compare your results with the literature.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

In this work, biochars prepared from bamboo and those separately modified by chitosan and iron were employed to treat heavy metal-containing wastewater in single and trinary systems. Though a lot of work has been carried out, I think some necessary work still needs to be done to make the manuscript meet the requirement of the journal. Accordingly, a major revision is needed. Some key comments are as follows:

1. The Abstract did not well present the results of the manuscript, specially for the merit of the work, which needs to be reorganized and rewritten.

2. It seems that the temperature for the preparation of bamboo biochar can be properly controlled according to the description in lines 122-124, how do the authors ensure the difference in quality of the biochars from different batches?

3. According to the description in lines 125-138, the binding forces of chitosan-bamboo biochar and iron-bamboo biochar are worrisome. The stability of the bamboo-based biochar needs to be investigated.

4. The metal composition contents of BC are generally higher than those of B except for K, how do the authors interpret this result?

5. According to Table 4, B possesses excellent adsorption capability to heavy metals in comparison with AC. However, the modifications using chitosan and iron only makes the capability improve slightly. What is the significance of the modifications?

6. BC shows the best adsorption capability among the adsorbents employed in single system. Why did the author not investigate its adsorption capability in trinary system?  

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

I found this paper very original and very interesting. Only a few misprints have to be corrected.

- line 157: was done

- line 349: may not be achieved [38].

- line 357: reference [41] cannot be found among references.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors corrected the Manuscript, so now it can be considered for publication.

Reviewer 2 Report

The authors has addressed the comments properly, I think the revised manuscript has reached the requirement of the Journal.