摘要
将滇池草海底泥在不同烧制温度下制成生物炭,并用元素分析法表征其元素组成,溴化钾压片法表征其红外光谱,CO2和N2法表征其比表面积、孔体积、孔径.以菲作为模型化合物来研究有机污染物在生物炭上的吸附-解吸行为,以此深入了解生物炭施用中对有机污染物环境行为和风险的影响.结果表明,生物炭随烧制温度升高,芳香性升高、亲水性降低、极性降低.生物炭随烧制温度升高,对水中菲的吸附能力不断增强.解吸滞后效应随生物炭烧制温度升高而不断增强,这与分配作用和孔隙填充作用有关.
As a new carbon-based material, biochar has attracted great research attention. In this study, biochars were derived at different temperatures from Dianchi Lake sediment which consists of more than 50% organic matter. These biochars were characterized for their elemental composition, functional groups, surface area, pore volume, pore diameter and sorption/desorption properties with phenanthrene. The C content in the biochars did not vary significantly with pyrolyzing temperatures, probably because the complexation of organic matter and inorganic mineral particles and the loss of other elements （such as O, N, H, and S） was not dramatic. Increased surface areas were observed for biochars with increasing pyrolysis temperature, b-q＇IR characterization showed decreasing --CH2- and --CH3 contents with increasing temperature, but --OH, C ~O, and C--O--C did not show obvious change. Biochar sorption with phenanthrene increased and desorption hysteresis increased with pyrolyzing temperature. The sorption isotherms were fitted well with Freundlich and dual mode models. But the dual mode model showed significant variation for the parameters and thus could not be applied to illustrate sorption mechanisms. The results from Freundlich model were the main discussion focus. The sorption nonlinearity increased with pyrolyzing temperature, which could be well explained by biochar properties. Phenanthrene sorption in biochars was 1--2 orders of magnitude higher than that in natural soils/sediments. The high sorption and strong desorption hysteresis of the biochar could reduce the environmental risks of phenanthrene.
出处
《环境化学》
CAS
CSCD
北大核心
2011年第12期2026-2031,共6页
Environmental Chemistry
基金
昆明理工大学学生课外学术科技创新基金课题(2010BA160)
国家自然科学基金(40973081
40803034)
教育部留学回国人员启动基金
云南省学术带头人后备人才项目资助
关键词
生物炭
多环芳烃
土壤改良
解吸滞后
非线性吸附.
biochar, polyromatic hydrocarbons, soil remediation, hysteresis, nonlinear sorption.
