摘要
为探究棉秆生物炭(棉秆炭)对重金属Zn(Ⅱ)的去除作用,利用水平管式炉分别在400℃、500℃、600℃热解温度下制备棉秆炭,进行Zn(Ⅱ)的吸附试验。对比棉秆炭、木质和煤质活性炭对不同浓度溶液中Zn(Ⅱ)的去除效果。分析棉秆炭的元素含量和官能团变化等性质,以揭示吸附机理。结果表明,棉秆的DTG曲线在327℃出现最大值,温度高于600℃时,DTG曲线趋于稳定,棉秆的热解基本完成。随热解温度的升高,炭产率、H/C和O/C元素比均下降,说明棉秆炭芳香化程度和碱性增强,含氧极性官能团数量减少,红外分析印证了以上结论。去除率上,棉秆炭与Zn(Ⅱ)初始浓度和热解温度负相关,木质活性炭与Zn(Ⅱ)初始浓度正相关;吸附量上,棉秆炭、木质和煤质活性炭与Zn(Ⅱ)初始浓度正相关,棉秆炭与热解温度负相关。当Zn(Ⅱ)溶液浓度为2 mg/L时,棉秆炭的吸附性能优于木质和煤质活性炭,当Zn(Ⅱ)溶液浓度为10 mg/L、50 mg/L时,木质活性炭的吸附性能优于棉秆炭和煤质活性炭。棉秆炭吸附Zn(Ⅱ)的机理包含配位反应和离子交换。
In order to explore the effect of removing Zn(Ⅱ)from aqueous solution by biochars derived from cotton stalk(cotton stalk biochar),three kinds of cotton stalk biochar were prepared at different pyrolysis temperature(400℃,500℃,600℃)in the horizontal tube furnace and the adsorption test of removing Zn(Ⅱ)from aqueous solution was carried out.The performance of removing Zn(Ⅱ)from different concentration solution by cotton stalk biochar,wood activated carbon and coal activated carbon were compared.It was analyzed the elemental content and functional groups of cotton stalk biochar to reveal the adsorption mechanism.The results indicated that the DTG curve of cotton stalk reached its maximum value at 327℃,and tended to be stable when the temperature was above 600℃,which indicating that the pyrolysis of cotton stalk has been completed.With the increase of pyrolysis temperature,the degree of aromatization and alkalinity of cotton stalk biochar were enhanced,and the number of oxygen-containing polar functional groups was decreased which was demonstrated by the decrease in carbon yield,H/C and O/C element ratios and the FTIR analysis.On the removal rate,cotton stalk biochar was negatively related to the Zn(Ⅱ)initial concentration and pyrolysis temperature,however the wood activated carbon was positively related to the Zn(Ⅱ)initial concentration.On the adsorption quantity,cotton stalk biochar,wood activated carbon and coal activated carbon were positively related to the Zn(Ⅱ)initial concentration and the cotton stalk biochar was negatively related to the pyrolysis temperature.The performance of removing Zn(Ⅱ)from aqueous solution by cotton stalk biochar was better than that of activated carbon derived from wood and coal when the initial concentration of Zn(Ⅱ)in solution was 2 mg/L.And the performance of removing Zn(Ⅱ)from aqueous solution by wood activated carbon was better than that of cotton stalk biochar and coal activated carbon when the initial concentration of Zn(Ⅱ)in solution was 10 mg/L a
作者
高亮
李志合
李玉峰
王绍庆
李宁
易维明
Gao Liang;Li Zhihe;Li Yufeng;Wang Shaoqing;Li Ning;Yi Weiming(School of Agricultural Engineering and Food Science,Shandong University of Technology,Shandong Research Center of Engineering and Technology for Clean Energy,Zibo,255000,China;Shandong Academy of Agricultural Machinery Sciences,Ji nan,250100,China)
出处
《中国农机化学报》
北大核心
2021年第2期197-202,共6页
Journal of Chinese Agricultural Mechanization
基金
国家重点研发计划项目(2019YFD1100600、2019YFD1100602)。
关键词
棉秆生物炭
官能团
活性炭
吸附法
重金属Zn(Ⅱ)
cotton stalk biochar
function groups
activated carbon
adsorption method
heavy metal Zn(Ⅱ)
