SOLID-PHASE EXTRACTION ON SILICA MODIFIED WITH CYCLIC ORGANOSILICONS

Modification of silica surface with cyclic organosilicon compounds and application of the modified silica to extraction and enrichment of mi croorganic pollution in water was studied. The silica was modified wit h hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane in low- and high-boiling n-alknnes. Modification was applied with catalyst or without. The results of modification were examined using solid phase e xtraction (SPE). The recoveries of tested compounds (i.e., chlorinated pesticides) by modified silica were compared with the recovery values obtained on commercial C-18 and spe-500 sorbents.