Agricultural residues are important renewable biomass resources that have not received much research attention. Ginger stalk is a major agricultural waste in China.The extraction of cellulose from ginger stalk would c...Agricultural residues are important renewable biomass resources that have not received much research attention. Ginger stalk is a major agricultural waste in China.The extraction of cellulose from ginger stalk would convert this waste into a high value-added product and, simultaneously, contribute to environmental protection. This research studied the characteristics of cellulose extracted from ginger stalk by two different treatments:(i) potassium hydroxide(KOH) treatment and(ii) nitric acid-ethanol(NAE) treatment. The optimal condition for the KOH treatment was obtained, it was at 1∶30 solidto-liquid ratio(SLR) for 5 h extraction time with 14 wt% KOH. The optimal condition for the NAE treatment was as follows: 1∶40 SLR, 4 h extraction time, and a reaction temperature of 90℃. However, the cellulose obtained by NAE treatment was severely degraded than that by KOH treatment. The Fourier-transform infrared(FT-IR) spectroscopy analyses revealed that both treatments successfully dissolved the lignin and hemicellulose. Two treatments showed a higher cellulose yield, and the extracted cellulose had more crystal structure.展开更多
Activated carbon （AC） obtained from the industrial pyrolytic tire char is treated by concentrated nitric acid （AC-HNO3） and then used as the electrode material for supercapacitors. Surface properties and electroch...Activated carbon （AC） obtained from the industrial pyrolytic tire char is treated by concentrated nitric acid （AC-HNO3） and then used as the electrode material for supercapacitors. Surface properties and electrochemical capacitances of AC and AC- HNO3 are studied. It is found that the morphology and the porous texture for AC and AC- HNO3 have little difference, while the oxygen content increases and functional groups change after the acid treatment. Electrochemical results demonstrate that the AC-HNO3 electrode displays higher specific capacitance, better stability and cycling performance, and lower equivalent series resistance, indicating that AC obtained from the industrial pyrolytic tire char treated by concentrated nitric acid is applicable for supercapacitors.展开更多
采用水热处理和硝酸处理相结合的方法对Y分子筛进行改性,并采用N2吸附-脱附、XRD、NH3-TPD、Py-FTIR、27Al MAS NMR、SEM等方法对改性前后的Y分子筛进行了表征.考察了不同改性方法对Y分子筛的孔结构、晶相结构、酸性以及Y分子筛催化剂...采用水热处理和硝酸处理相结合的方法对Y分子筛进行改性,并采用N2吸附-脱附、XRD、NH3-TPD、Py-FTIR、27Al MAS NMR、SEM等方法对改性前后的Y分子筛进行了表征.考察了不同改性方法对Y分子筛的孔结构、晶相结构、酸性以及Y分子筛催化剂加氢裂化性能的影响.实验结果表明,随水热处理温度的升高,Y分子筛的脱铝量增大,比表面积减小,总酸量降低;随硝酸浓度的增加,Y分子筛中的非骨架铝脱除,相对结晶度、比表面积和硅铝比增大.以改性后的Y分子筛制备的加氢裂化催化剂的活性和选择性得到改善,其中Y分子筛经680℃水热处理和0.6 mol/L硝酸处理后制备的加氢裂化催化剂,在保持较高正十二烷转化率的前提下,具有良好的中油（C4-8烃）选择性,中油收率为51.07％.展开更多
利用硝酸对颗粒活性炭进行改性,处理含铬废水,并考察了吸附时间、溶液pH、吸附剂加入量对改性活性炭吸附Cr(Ⅵ)效果的影响。实验结果表明:经过硝酸氧化改性的活性炭比表面积有所增加,官能团总量增加明显;吸附剂对Cr(Ⅵ)的去除率随振荡...利用硝酸对颗粒活性炭进行改性,处理含铬废水,并考察了吸附时间、溶液pH、吸附剂加入量对改性活性炭吸附Cr(Ⅵ)效果的影响。实验结果表明:经过硝酸氧化改性的活性炭比表面积有所增加,官能团总量增加明显;吸附剂对Cr(Ⅵ)的去除率随振荡时间的增加而增加;对于质量浓度为10 mg/L的100 mL Cr(Ⅵ)溶液,当溶液pH为中性,30%(体积分数)硝酸改性的颗粒活性炭的加入量为0.4 g,其对Cr(Ⅵ)的最大去除率为98%。展开更多
基金financial support from the National Basic Research Program of China ( Grant No.2014CB460610 )National Science Foundation of China (Grant Nos.2157061214 and 21406126)Department of Education of Shandong Province (Grant No.J14LC11)
文摘Agricultural residues are important renewable biomass resources that have not received much research attention. Ginger stalk is a major agricultural waste in China.The extraction of cellulose from ginger stalk would convert this waste into a high value-added product and, simultaneously, contribute to environmental protection. This research studied the characteristics of cellulose extracted from ginger stalk by two different treatments:(i) potassium hydroxide(KOH) treatment and(ii) nitric acid-ethanol(NAE) treatment. The optimal condition for the KOH treatment was obtained, it was at 1∶30 solidto-liquid ratio(SLR) for 5 h extraction time with 14 wt% KOH. The optimal condition for the NAE treatment was as follows: 1∶40 SLR, 4 h extraction time, and a reaction temperature of 90℃. However, the cellulose obtained by NAE treatment was severely degraded than that by KOH treatment. The Fourier-transform infrared(FT-IR) spectroscopy analyses revealed that both treatments successfully dissolved the lignin and hemicellulose. Two treatments showed a higher cellulose yield, and the extracted cellulose had more crystal structure.
基金This work was financially supported by the National Key Technologies R ＆ D Program of China （Grant No. 2006BAC02A12）, the National Natural Science Foundation of China （Grant No. 21003077）, the Natural Science Foundation of Tianjin （Grant No. 08JCZDJC21400） and MOE （IRT 13R30）.
文摘Activated carbon （AC） obtained from the industrial pyrolytic tire char is treated by concentrated nitric acid （AC-HNO3） and then used as the electrode material for supercapacitors. Surface properties and electrochemical capacitances of AC and AC- HNO3 are studied. It is found that the morphology and the porous texture for AC and AC- HNO3 have little difference, while the oxygen content increases and functional groups change after the acid treatment. Electrochemical results demonstrate that the AC-HNO3 electrode displays higher specific capacitance, better stability and cycling performance, and lower equivalent series resistance, indicating that AC obtained from the industrial pyrolytic tire char treated by concentrated nitric acid is applicable for supercapacitors.
文摘采用水热处理和硝酸处理相结合的方法对Y分子筛进行改性,并采用N2吸附-脱附、XRD、NH3-TPD、Py-FTIR、27Al MAS NMR、SEM等方法对改性前后的Y分子筛进行了表征.考察了不同改性方法对Y分子筛的孔结构、晶相结构、酸性以及Y分子筛催化剂加氢裂化性能的影响.实验结果表明,随水热处理温度的升高,Y分子筛的脱铝量增大,比表面积减小,总酸量降低;随硝酸浓度的增加,Y分子筛中的非骨架铝脱除,相对结晶度、比表面积和硅铝比增大.以改性后的Y分子筛制备的加氢裂化催化剂的活性和选择性得到改善,其中Y分子筛经680℃水热处理和0.6 mol/L硝酸处理后制备的加氢裂化催化剂,在保持较高正十二烷转化率的前提下,具有良好的中油（C4-8烃）选择性,中油收率为51.07％.
文摘利用硝酸对颗粒活性炭进行改性,处理含铬废水,并考察了吸附时间、溶液pH、吸附剂加入量对改性活性炭吸附Cr(Ⅵ)效果的影响。实验结果表明:经过硝酸氧化改性的活性炭比表面积有所增加,官能团总量增加明显;吸附剂对Cr(Ⅵ)的去除率随振荡时间的增加而增加;对于质量浓度为10 mg/L的100 mL Cr(Ⅵ)溶液,当溶液pH为中性,30%(体积分数)硝酸改性的颗粒活性炭的加入量为0.4 g,其对Cr(Ⅵ)的最大去除率为98%。
