The Synthesis Of Benzamidoxime And Its Application

ABSTRACT:Amidoxime compounds have strong complexing properties, and are used as metal-chelators or flotation reagents. Based on the review of amidoxime compounds, benzamidoxime was synthesized by ultrasonic and traditional methods in this dissertation. The technology conditions of these two methods were optimized. Moreover, the interaction of benzamidoxime with metal ions and its adsorption mechanism on the surfaces of copper oxide minerals were evaluated. Then, its flotation performances to copper oxide minerals were investigated.Using benzonitrile, hydroxylamine hydrochloride and sodium hydroxide as reactants, distilled water and ethanol as reaction solvents, using the ultrasonic cleaning device as reactor, benzamidoxime was synthesized under ultrasonic radiation. And the preferred test conditions were followed as:0.05mol benzonitrile,10ml water, molar ratio of benzonitrile, hydroxylamine hydrochloride to sodiumhydroxide1:1.3:1.73, reaction time8h and reaction temperature55℃, ultrasonic power200W (40kHz) and volume ratio of water to ethanol1:6. Under this condition, the yield of benzamidoxime was93.27%. The optimal test conditions for the traditional method were followed as:0.05mol benzonitrile,10ml water, molar ratio of benzonitrile, hydroxylamine hydrochloride to sodiumhydroxide1:1.3:1.53, reaction time16h, reaction temperature45℃, and volume ratio of water to ethanol1:6. Under this condition, the yield of benzamidoxime was91.42%. The results of synthetic methods indicated that through ultrasonic strengthening, reaction time is greatly shortened and benzonitrile’s yield increased. The target product was characterized by UV and IR spectrum.The results of UV spectra indicated that benzamidoxime might chemically react with Fe3+, Ag+or Cu2+ions in the experimental conditions, but no reaction of the compound with Zn2+, Fe2+, Co2+, Pb2+or Ni+ions was observed. The combined results of UV-visible and zeta potential measurements, XPS analysis, and the adsorption dynamics and thermodynamics revealed that benzamidoxime could chemically adsorbed on the surfaces of copper oxide minerals. The flotation results demonstrated benzamidoxime had feasable response to flotation recovery of copper oxide minerals.