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In this study, the flotation separation performances of malachite from calcite were investigated using a new chelating collector S-carboxymethyl-O, O’-dibutyl dithiophosphate (CMDTP) by micro-flotation tests, which showed that CMDTP exhibited a stronger collecting power and a better selectivity on malachite than octyl hydroxamic acid (OHA), 8-hydroxyquinoline (HQ) and sodium isobutyl xanthate (SIBX). In the flotation separation of artificially mixed minerals, malachite could be separated successfully from calcite at pH around 9.0 when using Na2S as a regulator. Its adsorption mechanism was also studied by FT-IR, zeta potential and XPS measurements, all of which confirmed that CMDTP showed a better affinity to malachite surface than to calcite surface. Furthermore, XPS provided obvious evidence that CMDTP could easily react with Cu2+ sites on malachite surface, and only a tiny adsorption occurred on calcite surface without Cu2+ ions.

In this paper, glucose oxidase (GOD) was immobilized in the course of sol–gel process of TEOS, and we cast the GOD-doped sol to different supports (silica gel and molecular sieve) to prepare the GOD columns. It was demonstrated that the activity of GOD remained high in sol–gel matrix. With the application of the GOD column prepared with sol–gel method to a flowing injection chemiluminescent system, glucose could be effectively determined with the linear range of the concentration in 3.5–70 μmol/l and the detection limit was at 0.6 μmol/l.