轻烃在海洋沉积物中的吸附与解吸行为研究

Experimental Research on the Behavior of the Absorption and Desorption of Light Hydrocarbons in Marine Sediments

模拟海洋微环境,向脱气的海洋沉积物中注入已知浓度的轻烃混合标准气体,探究轻烃在海洋沉积物中的吸附与解吸行为。吸附试验结果表明,溶解和吸附作用使各轻烃组分发生显著的变化,且引起低碳原子数轻烃的变化以溶解作用为主导,引起高碳原子数轻烃的变化以吸附作用为主导。同时,同碳数的烯烃较烷烃更容易被溶解,正构烷烃较异构烷烃更容易被吸附。解吸附实验表明,热解吸可以起到解吸附的作用,且溶解态轻烃相对于吸附态轻烃更容易被解吸。

The behaviors of absorption and desorption of light hydrocarbons in marine sediments were stud-ied in laboratory by injecting light hydrocarbon mixed standard gas into the degassing marine sediments. The results of absorption show that the changes of light hydrocarbons are caused by solution and absorp-tion primarily. The smaller the carbon numbers of light hydrocarbon molecules, the easier the solution. The bigger the carbon numbers of light hydrocarbon molecules, the easier the absorption. Meanwhile, the olefins are more prone to solution than the alkanes of the same number of carbon atoms,and the n-alkane are more prone to absorption than the i-alkane of the same number of carbon atoms. The results of desorption tests show that thermal desorption can play the role of desorption, and dissolved light hydrocarbons are more prone to desorption than absorbed ones.