%0 Journal Article
%T Adsorption of Methylene Blue from Water by the Biochars Generated from Crop Residues<br>农作物残体制备的生物质炭对水中亚甲基蓝的吸附作用
%A XU Ren-kou
%A ZHAO An-zhen
%A XIAO Shuang-cheng
%A YUAN Jin-hua
%A <br>徐仁扣
%A 赵安珍
%A 肖双成
%A 袁金华
%J 环境科学
%D 2012
%I 
%X Biochars were prepared from straws of rice, peanut and soybean and rice hull using a low temperature pyrolysis method and adsorption of methylene blue by these biochars were investigated with batch and leaching experiments. Results indicated that biochars have high adsorption capacity for methylene blue and followed the order: rice straw char>soybean straw char>peanut straw char>rice hull char. This order is generally consistent with the amount of negative charge and specific surface area of these biochars. While methylene blue was mainly adsorbed specifically by the biochars, because the adsorption of methylene blue increased with the increase of ionic strength and the adsorption led to the shift of zeta potential of biochar particles to positive value direction. Langmuir equation fitted the adsorption isotherms well and can be used to describe the adsorption behaviors of methylene blue by the biochars. The maximum adsorption capacity of methylene blue predicted by langmuir equation was 196.1, 169.5, 129.9 and 89.3 mmol·kg-1 for rice straw char, soybean straw char, peanut straw char and rice hull char, respectively. Leaching experiments show that rice hull char of 156 g can remove methylene blue from 30 L water containing 0.3 mmol·L-1 of methylene blue completely and the cumulative amount of methylene blue absorbed by the biochar reaches 57.7 mmol·kg-1. The biochars can be used as efficient adsorbents to remove methylene blue from waste water of dye.
%K agricultural byproduct
%K biochar
%K methylene blue
%K adsorption
%K waste water of dye
%K Zeta potential<br>农业废弃物
%K 生物质炭
%K 亚甲基蓝
%K 吸附
%K 染料废水
%K Zeta电位
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3FF3ABA7486768130C3FF830376F43B398E0C97F0FF2DD53&cid=A7CA601309F5FED03C078BCE383971DC&jid=64CD0AA99DD39F69401C615B85F123EF&aid=4189763B19B8AD45E2CC88BE83BC95FD&yid=99E9153A83D4CB11&vid=27746BCEEE58E9DC&iid=CA4FD0336C81A37A&sid=E22B6B8FE86DD8F9&eid=A020552C37306588&journal_id=0250-3301&journal_name=环境科学&referenced_num=1&reference_num=20