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What does O/C, H/C, C/N ratios indicate in a biochar?
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+ Sorption
+ Heavy metals
+ Adsorption
+ Pyrolysis
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Mojo Jojo
What does O/C, H/C, C/N ratios indicate in a biochar?
Hi Please refer to the following paper: Effect of thiourea-modified biochar on adsorption and fractionation of cadmium and lead in contaminated acidic soil. International Journal of Phytoremediation. DOI: 10.1080/15226514.2019.1678108
Hi Please refer to the following paper: Effect of thiourea-modified biochar on adsorption and fractionation of cadmium and lead in contaminated acidic soil. International Journal of Phytoremediation. DOI: 10.1080/15226514.2019.1678108
Dear@ Uddipta Nath O/C ratio indicates the polarity, and abundance of polar oxygen containing surface functional groups in biochar, higher the ratio more is the polar functional groups. Also, these groups actively takes part in adsorption of heavy metals. H/C ratio indicates the aromatically and stability of the biochar. Yes, all these ratios have a rage. You must visit the site of International Biochar Initiatives where you can find out more relevent information. Ample literature is also available for biochar characterization. You can refer the articles from J of analytical and applied pyrolysis, waste management and Bioresource technology,
Dear@ Uddipta Nath O/C ratio indicates the polarity, and abundance of polar oxygen containing surface functional groups in biochar, higher the ratio more is the polar functional groups. Also, these groups actively takes part in adsorption of heavy metals. H/C ratio indicates the aromatically and stability of the biochar. Yes, all these ratios have a rage. You must visit the site of International Biochar Initiatives where you can find out more relevent information. Ample literature is also available for biochar characterization. You can refer the articles from J of analytical and applied pyrolysis, waste management and Bioresource technology,
As biomass undergoes thermolysis, its original polymeric molecules are broken up and transformed giving rise to three products: syngas (CO, H2, CH4), bio-oil (acetic acid, phenolic-like compounds, alcohols, H2O etc) and biochar+minerals. As temperature increases the biochar is more dominated by polyaromatic compounds. We can illustrate this transformation from original biomass comprising of hemicellulose, cellulose and lignin to biochar using the H/C and O/C ratio in a van Krevelen diagram (http://www.publish.csiro.au/?paper=SR10010;ArticleInfluence of Pyrolysis Temperature on Physico-Chemical Prope... ). H/C and O/C ratios are used in the biochar community to estimate the stability of biochar in soil, which is important for calculating the carbon sequestration potential. In your case it may be of importance in determining the number of regeneration cycles. Not sure whether anyone looked at this. In addition, and as mentioned by Amita Shakya already, the O/C ratio can inform us about the general polarity of the material. To know the type and quantity of functional groups present you could try Boehm titration (ArticleImmobilization of heavy metal ions (CuII, CdII, NiII, and Pb... ; https://linkinghub.elsevier.com/retrieve/pii/S0008622313008981;http://linkinghub.elsevier.com/retrieve/pii/S0016706111001091). Be sure that your biochar has been washed to avoid interference. As O/C decreases with increasing temperature, the adsorption mechanism shifts from mainly ion exchange based to physisorption (van der Waals, London dipole). The sorption capacity should drop due to the weaker nature of physisorption, but typically the BET surface area increases exponentially (with increasing temperature) thus compensating for it. Something else you may wish to consider in certain adsorption systems is the presence of natural organic matter which competes with the heavy metals for the surface. An example can be found here (ArticleAdsorption of NPK fertilizer and humic acid on palm kernel s... ). As for the yield, since both H/C and biochar yield are correlated to temperature, these two (H/C vs biochar yield) should be too.
You could carry out a meta-analysis and develop a correlation between O/C ratio and heavy metal adsorption capacity. Since type of functional group, pH and BET surface area plays and important role too it may not be that straightforward. It may be advisable to contact an expert in statistics (e.g. Abbas F. M. Alkarkhi). Hope this helps?
As biomass undergoes thermolysis, its original polymeric molecules are broken up and transformed giving rise to three products: syngas (CO, H2, CH4), bio-oil (acetic acid, phenolic-like compounds, alcohols, H2O etc) and biochar+minerals. As temperature increases the biochar is more dominated by polyaromatic compounds. We can illustrate this transformation from original biomass comprising of hemicellulose, cellulose and lignin to biochar using the H/C and O/C ratio in a van Krevelen diagram (http://www.publish.csiro.au/?paper=SR10010;ArticleInfluence of Pyrolysis Temperature on Physico-Chemical Prope... ). H/C and O/C ratios are used in the biochar community to estimate the stability of biochar in soil, which is important for calculating the carbon sequestration potential. In your case it may be of importance in determining the number of regeneration cycles. Not sure whether anyone looked at this. In addition, and as mentioned by Amita Shakya already, the O/C ratio can inform us about the general polarity of the material. To know the type and quantity of functional groups present you could try Boehm titration (ArticleImmobilization of heavy metal ions (CuII, CdII, NiII, and Pb... ; https://linkinghub.elsevier.com/retrieve/pii/S0008622313008981;http://linkinghub.elsevier.com/retrieve/pii/S0016706111001091). Be sure that your biochar has been washed to avoid interference. As O/C decreases with increasing temperature, the adsorption mechanism shifts from mainly ion exchange based to physisorption (van der Waals, London dipole). The sorption capacity should drop due to the weaker nature of physisorption, but typically the BET surface area increases exponentially (with increasing temperature) thus compensating for it. Something else you may wish to consider in certain adsorption systems is the presence of natural organic matter which competes with the heavy metals for the surface. An example can be found here (ArticleAdsorption of NPK fertilizer and humic acid on palm kernel s... ). As for the yield, since both H/C and biochar yield are correlated to temperature, these two (H/C vs biochar yield) should be too.
You could carry out a meta-analysis and develop a correlation between O/C ratio and heavy metal adsorption capacity. Since type of functional group, pH and BET surface area plays and important role too it may not be that straightforward. It may be advisable to contact an expert in statistics (e.g. Abbas F. M. Alkarkhi). Hope this helps?
Hi
Please refer to the following paper:
Effect of thiourea-modified biochar on adsorption and fractionation of cadmium and lead in contaminated acidic soil. International Journal of Phytoremediation. DOI: 10.1080/15226514.2019.1678108
Hi
Please refer to the following paper:
Effect of thiourea-modified biochar on adsorption and fractionation of cadmium and lead in contaminated acidic soil. International Journal of Phytoremediation. DOI: 10.1080/15226514.2019.1678108
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THANKS
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Dear@ Uddipta Nath
O/C ratio indicates the polarity, and abundance of polar oxygen containing surface functional groups in biochar, higher the ratio more is the polar functional groups. Also, these groups actively takes part in adsorption of heavy metals. H/C ratio indicates the aromatically and stability of the biochar. Yes, all these ratios have a rage. You must visit the site of International Biochar Initiatives where you can find out more relevent information. Ample literature is also available for biochar characterization. You can refer the articles from J of analytical and applied pyrolysis, waste management and Bioresource technology,
Dear@ Uddipta Nath
O/C ratio indicates the polarity, and abundance of polar oxygen containing surface functional groups in biochar, higher the ratio more is the polar functional groups. Also, these groups actively takes part in adsorption of heavy metals. H/C ratio indicates the aromatically and stability of the biochar. Yes, all these ratios have a rage. You must visit the site of International Biochar Initiatives where you can find out more relevent information. Ample literature is also available for biochar characterization. You can refer the articles from J of analytical and applied pyrolysis, waste management and Bioresource technology,
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Thank you ..
Thank you ..
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Thank you for the useful information
Thank you for the useful information
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Very good! Nice
Very good! Nice
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thank you for valuable information brother@Robert Thomas
thank you for valuable information brother@Robert Thomas
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As biomass undergoes thermolysis, its original polymeric molecules are broken up and transformed giving rise to three products: syngas (CO, H2, CH4), bio-oil (acetic acid, phenolic-like compounds, alcohols, H2O etc) and biochar+minerals. As temperature increases the biochar is more dominated by polyaromatic compounds. We can illustrate this transformation from original biomass comprising of hemicellulose, cellulose and lignin to biochar using the H/C and O/C ratio in a van Krevelen diagram (http://www.publish.csiro.au/?paper=SR10010; Article Influence of Pyrolysis Temperature on Physico-Chemical Prope...
). H/C and O/C ratios are used in the biochar community to estimate the stability of biochar in soil, which is important for calculating the carbon sequestration potential. In your case it may be of importance in determining the number of regeneration cycles. Not sure whether anyone looked at this. In addition, and as mentioned by Amita Shakya already, the O/C ratio can inform us about the general polarity of the material. To know the type and quantity of functional groups present you could try Boehm titration (Article Immobilization of heavy metal ions (CuII, CdII, NiII, and Pb...
; https://linkinghub.elsevier.com/retrieve/pii/S0008622313008981; http://linkinghub.elsevier.com/retrieve/pii/S0016706111001091). Be sure that your biochar has been washed to avoid interference.
As O/C decreases with increasing temperature, the adsorption mechanism shifts from mainly ion exchange based to physisorption (van der Waals, London dipole). The sorption capacity should drop due to the weaker nature of physisorption, but typically the BET surface area increases exponentially (with increasing temperature) thus compensating for it. Something else you may wish to consider in certain adsorption systems is the presence of natural organic matter which competes with the heavy metals for the surface. An example can be found here (Article Adsorption of NPK fertilizer and humic acid on palm kernel s...
).
As for the yield, since both H/C and biochar yield are correlated to temperature, these two (H/C vs biochar yield) should be too.
You could carry out a meta-analysis and develop a correlation between O/C ratio and heavy metal adsorption capacity. Since type of functional group, pH and BET surface area plays and important role too it may not be that straightforward. It may be advisable to contact an expert in statistics (e.g. Abbas F. M. Alkarkhi).
Hope this helps?
As biomass undergoes thermolysis, its original polymeric molecules are broken up and transformed giving rise to three products: syngas (CO, H2, CH4), bio-oil (acetic acid, phenolic-like compounds, alcohols, H2O etc) and biochar+minerals. As temperature increases the biochar is more dominated by polyaromatic compounds. We can illustrate this transformation from original biomass comprising of hemicellulose, cellulose and lignin to biochar using the H/C and O/C ratio in a van Krevelen diagram (http://www.publish.csiro.au/?paper=SR10010; Article Influence of Pyrolysis Temperature on Physico-Chemical Prope...
). H/C and O/C ratios are used in the biochar community to estimate the stability of biochar in soil, which is important for calculating the carbon sequestration potential. In your case it may be of importance in determining the number of regeneration cycles. Not sure whether anyone looked at this. In addition, and as mentioned by Amita Shakya already, the O/C ratio can inform us about the general polarity of the material. To know the type and quantity of functional groups present you could try Boehm titration (Article Immobilization of heavy metal ions (CuII, CdII, NiII, and Pb...
; https://linkinghub.elsevier.com/retrieve/pii/S0008622313008981; http://linkinghub.elsevier.com/retrieve/pii/S0016706111001091). Be sure that your biochar has been washed to avoid interference.
As O/C decreases with increasing temperature, the adsorption mechanism shifts from mainly ion exchange based to physisorption (van der Waals, London dipole). The sorption capacity should drop due to the weaker nature of physisorption, but typically the BET surface area increases exponentially (with increasing temperature) thus compensating for it. Something else you may wish to consider in certain adsorption systems is the presence of natural organic matter which competes with the heavy metals for the surface. An example can be found here (Article Adsorption of NPK fertilizer and humic acid on palm kernel s...
).
As for the yield, since both H/C and biochar yield are correlated to temperature, these two (H/C vs biochar yield) should be too.
You could carry out a meta-analysis and develop a correlation between O/C ratio and heavy metal adsorption capacity. Since type of functional group, pH and BET surface area plays and important role too it may not be that straightforward. It may be advisable to contact an expert in statistics (e.g. Abbas F. M. Alkarkhi).
Hope this helps?
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Very interesting points discussed.. good to know
Very interesting points discussed.. good to know
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Interesting discussion. Follow.
Interesting discussion. Follow.
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Nice discussion. I have really gain a lot of useful insight
Nice discussion. I have really gain a lot of useful insight
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