Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to p...Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to process agricultural waste for heavy metal adsorption purpose.The objective of this study is to propose a new approach to treat banana peel using ZnCl_(2) prior to alkali and acid treatment and explore the potential of dragon fruit peels as the adsorbent for Cu^(2+)adsorption.Seven adsorption isotherm was adopted to identify the adsorption mechanism and four statistical parameters were calculated for model verification purpose.The experiment was conducted by dispersing ZnCl_(2) treated and untreated adsorbents into Cu^(2+) solution.Results showed that ZnCl_(2) treated adsorbents performed better in terms of Cu^(2+) removal compared with untreated adsorbents due to higher surface area for Cu^(2+) adsorption.The treated banana peel(Act.-B)performed approximately 30%better than the treated dragon fruit peel(Act.-D)due to the presence of hydroxyl and carboxyl groups.The equilibrium adsorptive capacity of Act.-B was 1872.8 mg Cu^(2+)/g and the experimental data fitted Freundlich isotherm well with R^(2)=0.9978,0.0161 of residual sum of error(SSE),0.0068 of χ^(2),and 0.0567 of root mean square error(RMSE)values.This suggests non⁃linear adsorption and multilayer adsorption on heterogenous surfaces.Thus,it is recommended to further improve the surface properties of Act.-B by steam pyrolysis and surface modification.展开更多
文摘Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to process agricultural waste for heavy metal adsorption purpose.The objective of this study is to propose a new approach to treat banana peel using ZnCl_(2) prior to alkali and acid treatment and explore the potential of dragon fruit peels as the adsorbent for Cu^(2+)adsorption.Seven adsorption isotherm was adopted to identify the adsorption mechanism and four statistical parameters were calculated for model verification purpose.The experiment was conducted by dispersing ZnCl_(2) treated and untreated adsorbents into Cu^(2+) solution.Results showed that ZnCl_(2) treated adsorbents performed better in terms of Cu^(2+) removal compared with untreated adsorbents due to higher surface area for Cu^(2+) adsorption.The treated banana peel(Act.-B)performed approximately 30%better than the treated dragon fruit peel(Act.-D)due to the presence of hydroxyl and carboxyl groups.The equilibrium adsorptive capacity of Act.-B was 1872.8 mg Cu^(2+)/g and the experimental data fitted Freundlich isotherm well with R^(2)=0.9978,0.0161 of residual sum of error(SSE),0.0068 of χ^(2),and 0.0567 of root mean square error(RMSE)values.This suggests non⁃linear adsorption and multilayer adsorption on heterogenous surfaces.Thus,it is recommended to further improve the surface properties of Act.-B by steam pyrolysis and surface modification.
