Agricultural waste straw is the renewable resource with the highest annual yield in the world.In value-added applications of agricultural waste,dicarboxyl cellulose nanocrystals(DCCs)are prepared from rice,wheat,and c...Agricultural waste straw is the renewable resource with the highest annual yield in the world.In value-added applications of agricultural waste,dicarboxyl cellulose nanocrystals(DCCs)are prepared from rice,wheat,and corn straw by sequential periodate-chlorite oxidation.In this study,DCCs from rice,wheat,and corn straw were characterized by transmission electron microscopy(TEM),Fourier transform infrared spectrometer,X-ray diffractometer(XRD),and thermal gravimetric analysis(TGA).The carboxyl content of the DCCs was also investigated.XRD results show that the crystallinity index decreased after sequential periodate-chlorite oxidation;however,the cellulose I structure was maintained.TEM results show that rod-shaped DCCs with an average length and width of 287.0 nm and 9.9 nm,respectively,were successfully prepared by sequential periodate-chlorite oxidation.The carboxyl content of the DCCs was around 3.9 mmol/g,and not affected by the type of straw.Experiments to study the removal of copper ions in aqueous medium were performed with the prepared DCCs.The adsorption capacities of copper ions were 131,162,and 144 mg/g for DCCs prepared from rice,wheat,and corn straws,respectively.The results show that DCCs prepared from rice,wheat,and corn straws by sequential periodatechlorite oxidation have potential for the removal of copper ions from aqueous medium.展开更多
The water crisis is an increasingly severe global problem that may be reduced by reusing wastewater after suitable treatment methods. Nowadays, biosorption is one of the main parts of environmental technology which co...The water crisis is an increasingly severe global problem that may be reduced by reusing wastewater after suitable treatment methods. Nowadays, biosorption is one of the main parts of environmental technology which could adsorb heavy metals. This paper describes the adsorption of Copper(II) ions from aqueous solution using a mixture of corn stalk and tomato waste which were oxidized with nitric acid. Kinetic and isotherm studies were carried out by studying the effects of parameters such as concentration dosage, time and pH. It was found that the maximum sorption capacity of the mixture of modified corn stalk and modified tomato waste (q<sub>m</sub> = 25 mg/g) was higher than the modified corn stalk (q<sub>m</sub> = 20.8 mg/g). Analysis indicated that pseudo-second-order kinetics controlled the adsorption rate and it has been proposed to correlate the experimental data well.展开更多
文摘Agricultural waste straw is the renewable resource with the highest annual yield in the world.In value-added applications of agricultural waste,dicarboxyl cellulose nanocrystals(DCCs)are prepared from rice,wheat,and corn straw by sequential periodate-chlorite oxidation.In this study,DCCs from rice,wheat,and corn straw were characterized by transmission electron microscopy(TEM),Fourier transform infrared spectrometer,X-ray diffractometer(XRD),and thermal gravimetric analysis(TGA).The carboxyl content of the DCCs was also investigated.XRD results show that the crystallinity index decreased after sequential periodate-chlorite oxidation;however,the cellulose I structure was maintained.TEM results show that rod-shaped DCCs with an average length and width of 287.0 nm and 9.9 nm,respectively,were successfully prepared by sequential periodate-chlorite oxidation.The carboxyl content of the DCCs was around 3.9 mmol/g,and not affected by the type of straw.Experiments to study the removal of copper ions in aqueous medium were performed with the prepared DCCs.The adsorption capacities of copper ions were 131,162,and 144 mg/g for DCCs prepared from rice,wheat,and corn straws,respectively.The results show that DCCs prepared from rice,wheat,and corn straws by sequential periodatechlorite oxidation have potential for the removal of copper ions from aqueous medium.
文摘The water crisis is an increasingly severe global problem that may be reduced by reusing wastewater after suitable treatment methods. Nowadays, biosorption is one of the main parts of environmental technology which could adsorb heavy metals. This paper describes the adsorption of Copper(II) ions from aqueous solution using a mixture of corn stalk and tomato waste which were oxidized with nitric acid. Kinetic and isotherm studies were carried out by studying the effects of parameters such as concentration dosage, time and pH. It was found that the maximum sorption capacity of the mixture of modified corn stalk and modified tomato waste (q<sub>m</sub> = 25 mg/g) was higher than the modified corn stalk (q<sub>m</sub> = 20.8 mg/g). Analysis indicated that pseudo-second-order kinetics controlled the adsorption rate and it has been proposed to correlate the experimental data well.
