Synthesis Of New Schiff-base Compounds As Collectors In Flotation Separation Of Copper Oxide Ore

It is important to develop high selective collectors for copper oxide ore. Chelating compounds are widely used as colloctors in flotation of the copper oxide ore in past decades.This thesis is aimed at investigating the flotation performance of malachite and quartz by seven kinds of Schiff-base compounds synthesized in the laboratory. On the base of flotation results,Chemical methods like zeta potential,FI-IR and the B3LYP/6-31 g of DFT are ued to investigate the adsorption mechanism in the respect of Macro and micro between malachite and Schiff base collectors.Seven kinds of Schiff-base collectors, phenylamine shrink salicylaldehyde Schiff-base,o-aminopheno shrink Benzaldehyde Schiff-base,hexamine shrink salicylaldehyde Schiff-base, tetramine shrink salicylaldehyde,cyclohexylamine shrink salicylaldehyde Schiff-base, furfural benzoin oxime, and alpha-Benzoin oxime are synthesized from the materials of Aldehydes, ketones compounds and the Corresponding Amine compounds.Futhermore, all products are Characterized by the ways of FI-IR and HNMR.Single mineral malachite or quartz flotation experiments show that the collectors A1,A2,A3,A4 and A5 have strong collecting abilities, but A6 and A7 have a few of collecting abilities. Futhermore, the collecting abilities of these collectors are listed as follows,A1>A2>A3≈A5>A4>A6>A7. The collecting abilities are greatly improved especially A6 and A7 when Schiff-base collectors mixed with diesel oil. The isomeric and the homolog principles can be applied to design the collector through investigating the structures of molecules. What’s more, the flotation recovery will increase with the growth of carbon chain.Selection A1, A6 and A7 with diesel as mixing collecting agents in flotation of simulation ore mingle by malachite and quartz, the results show that recovery of malachite can reach 80%,and the grade degree can reach 90% or more.The adsorption mechanism between malachite and Schiff-base collectors is chemical adsorption, which is investigated by Zeta potential and FI-IR. The adsoption effects existance due to chemical bonds formed from the group of C=N, –OH and cations on the surface of malachite. However,there are no adsorption effects between quartz and Schiff-base collectors.Optimal structures of these kinds of Schiff-base compounds are got by the calculative way of B3LYP/6-31 g of DFT.The LUMO, HOMO and the energy gap(?E) between LUMO and HOMO are obtained from the optimal structures. The collecting abilities of Schiff-base compounds received from ?E, which is corresponding with the results of flotation experiments.