玉米秸秆与甘蔗渣生物炭的制备及其对Cr^(6+)离子的吸附性能研究

Preparation of Biochar from Corn Stalk and Bagasse and its Adsorption of Cr^(6+)

以Cr^(6+)的清除率为评价指标,研究不同时间、温度、配比条件下的生物炭吸附性能,优化玉米秸秆与甘蔗渣生物炭的制备过程。采用单因素试验和正交试验研究生物炭的吸附性能,单因素试验是研究炭化时间、炭化温度、生物炭配比对生物炭吸附性能的影响。正交试验是通过单因素试验选取比较优异的试验条件进行L9(34)的正交试验,通过分析比较得出最佳试验条件。单因素试验发现,混合生物炭对Cr^(6+)的清除率在炭化时间1.5 h,炭化温度500℃,生物炭配比0.50∶0.50时达到最高;正交试验极差分析和方差分析发现,炭化时间对Cr^(6+)的吸附性能影响比较显著,而炭化温度、生物炭配比对Cr^(6+)的吸附性能影响不显著,最佳吸附条件为炭化时间2.0 h,炭化温度450℃,生物炭配比0.50∶0.50,在此条件下制备的混合生物炭对Cr^(6+)的清除率可达88.74%。

The preparation process of bio-carbon from corn stalk and bagasse was optimized by using the scavenging rate ofCr6＋ as an index to study the adsorption of biochar under different conditions including time,muffle temperature and biocharratio. The adsorption properties of biochar were studied by single factor method and orthogonal method. Single factor methodstudied the effect of time,temperature and proportion of biochar. By selecting single factor method,the excellent times,muffletemperature and biochar ratios were selectde,and then the orthogonal experiment of L9（34）was carried out,and the best experimentalconditions were found through analysis and comparison. Single factor experiment found that the highest removal rateof Cr6＋ in aqueous solution was carbonization time 1.5 h,the temperature 500 ℃,and the ratio 0.50∶0.50. The orthogonalexperiment analysis and variance analysis showed that carbonization time had a significant effect on the adsorption performanceof Cr6＋,and the effect of muffle temperature and biochar ratio were not significant. The optimum adsorption condition was carbonizationtime 2.0 h,muffle tem