摘要
生物炭作为一种绿色环保的功能材料因其在污水处理和污染土壤修复方面具有显著效果而受到极大关注。采用红外光谱、元素分析仪及微孔分析对不同温度(200、300、400、500和600℃)条件下制备的木屑和麦秆生物炭进行特性表征,并采用制备的生物炭净化石油污染土壤,分别考察了污染物性质、生物质原料和热解温度对其净化效果的影响。结果表明,随着热解温度的增高,生物炭芳香化程度增加,极性降低,微孔结构逐渐发育,表面积增大。加入生物炭33 d后,污染土壤中总石油烃及其组分烷烃的浓度比对照略有降低,而PAHs浓度下降显著。随着热解温度升高,2种生物炭对PAHs的吸附强度均逐渐增大,芳香度增高、表面积增大是强吸附的主要原因。2种生物炭在400℃及以下温度制备时对PAHs的吸附强度为:木屑生物炭>麦秆生物炭;而400℃以上温度制备的生物炭吸附强度则相反,即麦秆生物炭>木屑生物炭,说明生物炭原料对其吸附强度也具有显著影响。
In recent years,there has been growing interest in utilizing biochars to mitigate and clean up soil contamination. In this study,sawdust and wheat straw were pyrolyzed at five temperatures(200,300,400,500 and 600℃),and characterized for elemental compositions,BET surface area( BET SA),total pore volume(TPV) and functional groups. The resultant biochars were utilized to remediate petroleum hydrocarbon contaminated soils as a sorbent,which might be influenced by the contaminants targeted and how the biochar was prepared. Biochars from sawdust and wheat straw behaved similarly. The BET SA and TPV of biochars increased as preparation temperature increased,while the amount of functional groups decreased. Two biochars showed notable sorption capability for polycyclic aromatic hydrocarbons( PAHs) after a 33 day-incubation,but no apparent effects on alkanes. Such experimental results were considered to be significantly influenced by the structural characteristics of contaminants. Moreover,increasing the pyrolysis temperature promoted the affinity of PAHs to sawdust and wheat straw biochars,since biochars with high aromaticity and BET SA could supply more active sorption sites. The sorption of biochars prepared at and below 400℃ to PAHs increased in the following order:sawdust biochar > wheat straw biochar,while it turned to the opposite when the biochars prepared above 400℃.These results indicated that the sorption capacity of biochar might depend on the source of biomass used.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第5期2462-2468,共7页
Chinese Journal of Environmental Engineering
基金
国家"863"高技术研究发展计划项目重大课题(2013AA06A205)
国家自然科学基金重点资助项目(U1133006)
南开大学重大培育项目(65030051)
关键词
生物炭
土壤环境
石油烃污染
热解温度
生物质原料
biochar
soil environment
petroleum hydrocarbon contamination
pyrolysis temperature
bio-mass raw material
