The Effect of Different Biochar on the Mechanical Properties of Cement-Pastes and Mortars
, Devid Falliano 1, Juan Felipe Carvajal 1, Adriana Carolina Bravo Celi 1, Giuseppe Andrea Ferro 1, Jean Marc Tulliani 2, Luca Lavagna 2,* and Luciana Restuccia 1Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors presented their own experimental research on possibly utilizing biomass by-products in more environmentally friendly cement-based composites. Aiming to increase the interest of the readers and improve the significance and overall quality of presented results, the authors should carry out the following:
- The Introduction part should contain data on the available numbers of biomass waste (woody and agricultural), generated biochar waste quantities, and biomass ashes amounts in the studied region and some other countries/regions.
- The authors underlined the benefits of using biochar (Introduction part); however, some obstacles/disadvantages, as well as the gaps in the available literature should be cited/mentioned in order to demonstrate the significance of this research.
- The chemical composition of biochar should be tested and provided within the characterization of the material.
- Photos illustrating the appearance of biochar and conducted tests should be incorporated into the article.
- The authors should elaborate on why they used biochar in adopted percentages. Related to that, a hypothesis should be highlighted in the article.
- Chapter 3.1.2 - particle size distribution of cement should be inserted in Figure 1. This would help explain the filler effect actions in the following chapters.
- Lines 346-348: Proper references on filler effect should be given. Proposal: https://doi.org/10.3390/ma16062443
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe paper submitted for publication is a simple study on mechanical properties of cement and mortars upon addition of biochar. Authors’ goal is clearly to demonstrate that the addition of a bio-based filler in concrete can reduce carbon footprint of the construction industry without deteriorating the performances, or, even better as shown in this study, to improve them even further.
The paper is well written, easy to follow and to understand. Methodology is correct, description is accurate and results are presented clearly with just few figures.
My comment is about the char characterization, in particular the TGA analysis. What is the purpose of including this information in the paper? It seems irrelevant for the discussion since there is no correlation between TGA results and what observed studying mechanical properties of mortars and cement. Besdies, Can Authors argument why TGA was performed in flowing air atmosphere (L144) and not inert atmosphere? Clearly, heating a carbon-based feedstock up to 1000°C in presence of oxidant (air), will result in its oxidation and mass loss. Usually, TGA are performed in inert atmosphere in similar case. Authors are requested to motivate why TGA performed in this way provide useful information to the work or to remove it.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsNo further issues detected.
