Mercury
Mercury
Mercury
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The relationship between molecular<br />
structure and the bio-degradation of<br />
surface active agent<br />
• The biological degradability of surface active agent depends<br />
mainly on the hydrophobic groups. With the linearity ( 线 性 程<br />
度 ) of hydrophobic groups, the degradability of the<br />
quaternary carbon atom at the end of the chain is<br />
significantly reduced with more hydrophobic groups;<br />
• The properties of the hydrophilic groups also have some<br />
influence on the biological degradability. e.g. LPAS( 直 链 伯 烷<br />
基 硫 酸 盐 ) has higher primary bio-degradation speed than<br />
other anions; short-EO-chain polyoxyethylene ( 聚 氧 乙 烯 )<br />
nonionic surfactants are bio-degraded more easily.<br />
• The increase of the distance between between the sulfo ( 磺<br />
基 ) and the end of the hydrophobic groups can raise the<br />
primary bio-degradability of methyl benzene sulfonates<br />
(distance principle).