Samples of ground nut hull were converted to biosorbents using microwave assisted method [groundnut hull treated with hydrogen peroxide (HP-GH), groundnut hull treated with distilled water (W-GH) and raw groundnut hul...Samples of ground nut hull were converted to biosorbents using microwave assisted method [groundnut hull treated with hydrogen peroxide (HP-GH), groundnut hull treated with distilled water (W-GH) and raw groundnut hull (R-GH)]. The biosorbents were further characterized using physicochemical procedures (pH dependence, bulk density, surface area, ash content, and volatile matter, moisture content). The results show that HP-GH has pH = 8.9, W-GH pH = 8.4 and R-GH pH = 8.5 which is an indication that all the biosorbents have the appropriate pH values for the uptake of cationic species within aqueous systems. Surface area analysis revealed that HP-GH has the largest surface area (74.20 m<sup>2</sup>·g<sup>-1</sup>) while W-GH and R-GH have surface area values of 29.40 m<sup>2</sup>·g<sup>-1</sup> and 21.40 m<sup>2</sup>·g<sup>-1</sup> respectively. This suggests that modification of raw groundnut hull biomass with hydrogen peroxide possibly instigated delignification of the biomass which resulted in increased surface area for HP-GH. Results from Bulk density analysis also confirm the data obtained from surface area analysis. Accordingly, R-GH displayed the highest bulk density followed by W-GH with HP-GH showing the least bulk density. The variation in pH values among the biomass used in this study may be explained by the variation in their ash content as well because pH and ash content are positively correlated. Hence, HP-GH with a pH = 8.9 has high ash content (117.31%), W-GH with pH = 8.4 has 97.93% ash content and R-GH with pH = 8.5 has 94.26% ash content. Results from moisture content analysis show that HP-GH (99.95%), W-GH (99.97%) and R-GH (99.89%) may necessitate exposure of the biosorbents to moderate heat before use. The results obtained from this study suggest that modification of ground nut hull with either distilled water or Hydrogen peroxide by means of microwave irradiation improves physicochemical properties which may perhaps increase the adsorption capacity of the biomass.展开更多
Biomass is a renewable energy source because sun energy is stored in the form of biomass which regrows over a relatively short period as compared to fossil fuel. The biomass on burning released energy with emission of...Biomass is a renewable energy source because sun energy is stored in the form of biomass which regrows over a relatively short period as compared to fossil fuel. The biomass on burning released energy with emission of carbon dioxide, volatile organic compounds, particulate matters and ash residue. The combustion characteristics of biomass depends on several factors of plants i.e. bulk density, moisture, organic matter and metal content. In this work, the combustion characteristics i.e. heat value, moisture, volatile matter and ash content as well as emission fluxes of particulate matters (PM<sub>10</sub>) of trees grown in central India are described. The calorific value (CV) of 53 trees was ranged from 5190 - 8130 kcal/kg with mean value (p = 0.05) of 6380 ± 170 kcal/kg. Bahera tree showed the highest CV, 8130 kcal/kg, and hence, it was chosen for the detailed studies.展开更多
文摘Samples of ground nut hull were converted to biosorbents using microwave assisted method [groundnut hull treated with hydrogen peroxide (HP-GH), groundnut hull treated with distilled water (W-GH) and raw groundnut hull (R-GH)]. The biosorbents were further characterized using physicochemical procedures (pH dependence, bulk density, surface area, ash content, and volatile matter, moisture content). The results show that HP-GH has pH = 8.9, W-GH pH = 8.4 and R-GH pH = 8.5 which is an indication that all the biosorbents have the appropriate pH values for the uptake of cationic species within aqueous systems. Surface area analysis revealed that HP-GH has the largest surface area (74.20 m<sup>2</sup>·g<sup>-1</sup>) while W-GH and R-GH have surface area values of 29.40 m<sup>2</sup>·g<sup>-1</sup> and 21.40 m<sup>2</sup>·g<sup>-1</sup> respectively. This suggests that modification of raw groundnut hull biomass with hydrogen peroxide possibly instigated delignification of the biomass which resulted in increased surface area for HP-GH. Results from Bulk density analysis also confirm the data obtained from surface area analysis. Accordingly, R-GH displayed the highest bulk density followed by W-GH with HP-GH showing the least bulk density. The variation in pH values among the biomass used in this study may be explained by the variation in their ash content as well because pH and ash content are positively correlated. Hence, HP-GH with a pH = 8.9 has high ash content (117.31%), W-GH with pH = 8.4 has 97.93% ash content and R-GH with pH = 8.5 has 94.26% ash content. Results from moisture content analysis show that HP-GH (99.95%), W-GH (99.97%) and R-GH (99.89%) may necessitate exposure of the biosorbents to moderate heat before use. The results obtained from this study suggest that modification of ground nut hull with either distilled water or Hydrogen peroxide by means of microwave irradiation improves physicochemical properties which may perhaps increase the adsorption capacity of the biomass.
文摘Biomass is a renewable energy source because sun energy is stored in the form of biomass which regrows over a relatively short period as compared to fossil fuel. The biomass on burning released energy with emission of carbon dioxide, volatile organic compounds, particulate matters and ash residue. The combustion characteristics of biomass depends on several factors of plants i.e. bulk density, moisture, organic matter and metal content. In this work, the combustion characteristics i.e. heat value, moisture, volatile matter and ash content as well as emission fluxes of particulate matters (PM<sub>10</sub>) of trees grown in central India are described. The calorific value (CV) of 53 trees was ranged from 5190 - 8130 kcal/kg with mean value (p = 0.05) of 6380 ± 170 kcal/kg. Bahera tree showed the highest CV, 8130 kcal/kg, and hence, it was chosen for the detailed studies.
