材料期刊网

生物炭一旦施用到环境中以后,其物理化学性质可能会发生改变.然而,由于生物炭难以从土壤颗粒中分离出来,从而制约了对其施用后性质和功能的动态描述.苯多酸(BPCAs)是稠环芳烃的氧化产物,其作为生物标记物质能对炭黑的含量和特性进行描述.本研究尝试将苯多酸生物标记物技术用于生物炭性质研究中,以不同生物质(玉米秸秆和松木屑)在不同温度(200-500℃)下制备的生物炭为研究对象,通过元素分析及BPCAs生物标记物测定,对生物炭含量及特性进行描述.研究结果表明,BPCAs与元素分析对生物炭性质和特性的描述结果一致,BPCAs的含量随制备温度增加而增加,玉米秸秆生物炭中BPCAs含量从109 mg·g-1 C增加到426 mg·g-1 C,松木屑生物炭中BPCAs含量从21 mg·g-1 C增加到456 mg·g-1 C.B6CA所占百分比也随制备温度增加而增大,表明生物炭芳香缩合度随制备温度增加而增加.这一结果显示,BPCAs生物标记物方法有可能对生物炭的含量和特性进行一定的描述,生物标记物技术的引入,将为动态理解生物炭性质提供有力的工具.

Chemical and physical properties biochars may be altered after their application in the environment.However,it is not applicable to separate biochar particles from soil particles,which hinders the evaluation of biochar properties and their functions after their application.Benzene polycarboxylic acids (BPCAs) have been used as biomarkers and provided useful information to describe the quantity and property of black carbon,and have been successfully applied in soils and sediments.It will be useful to obtain biochar properties through BPCAs biomarkers.In this study,we compared the characterization of biochars using elemental analysis and BPCAs biomarkers.Biochars were made from corn straw and pine sawdust.These biomasses were pyrolyzed at 4 different temperatures (200-500 ℃).Their elemental compositions and molecular biomarkers were determined.The content showed consistent results for elemental composition and biomarker analysis.The content of BPCAs increased with pyrolysis temperature.For example,BPCAs contents increased from 109 mg·g-t C to 426 mg·g-1 C for corn straw biochars,and BPCAs contents for pine sawdust biochars increased from 21 mg·g-1 C to 456 rag·g-1 C.The contents of B6CA in BPCAs were also increased with pyrolysis temperature.These results suggest that BPCAs content and distribution will provide useful information to understand biochar properties.Introducing BPCAs biomarkers in biochar technique will enhance our ability for biochar application and management.