Investigation On The Behavior Of Ammonium Salt Roasted With Copper Sulfate And Copper Oxide

With the increasing demand of copper in modern society,it is significant to make use of copper resources in an efficient as well as environmentally friendly way.Ammonium salt roasting method is one of the effective ways to treat the copper ores,and which has been successfully applied to the production of copper resources.Although many researches are studied of ammonium salt roasting method,they aren't focused on the transition behavior of ammonium salt roasting with both copper sulfate and copper oxide.In order to extract copper more efficiently,it is necessary doing some further research about the transition behavior of ammonium salt roasting with both copper sulfate and copper oxide.This paper mainly focused on the study of the transformation behavior and mechanism of copper oxide and copper sulfide treated by ammonium salt roasting method with ammonium chloride and ammonium sulfate,thus providing theoretical base for treating copper ores by ammonium salt roasting.The main conclusions were as follows:?1?Copper oxide and copper sulfide were separately roasted by ammonium sulfate.The clinker was detected by TG-DTA analysis and identified by XRD method,it showed that,?NH4?2Cu?SO4?2 was generated at 200 ?.With the temperature raising or the roasting time extending,?NH4?2Cu?SO4?2 formed into?NH4?2Cu3?SO4?4,which eventually decomposed into CuSO4.The roasting clinker was also analysis by infra spectroscopy.It is seen that the peaks at 610cm^-1 1100cm^-1 is characteristic picks of sulfate radical.The peak at 1100cm^-1 was split.It means that the sulfate radical transform from free state to bidentate bonding.Because of the change,the peaks of degenerate oscillation split into several peaks.It proves that coordination reaction has happened between sulfate radical and copper.?2?Copper oxide and copper sulfide were separately roasted by ammonium chloride.In TG-DTA experiments,we can obviously find the formation of cuprous chloride.Combined with XRD analysis,copper oxide was transformed into NH4CUCl3 at 200?.When the temperature raised to 240 ?,NH4CUCl3 would decompose into cuprous chloride.By thermodynamics analysis,we know that:in copper oxide experiments,copper oxide reacted with ammonium chloride to form copper chloride,which would react with ammonium chloride furtherly to form cuprous chloride;while copper sulfide first reacted with ammonium chloride to form cuprous sulfide,which turned out to be cuprous chloride by reacting with ammonium chloride.?3?In leaching process,the leaching rate of copper was better when roasting with ammonium sulfate than ammonium chloride.For one thing,copper sulfate formed in ammonium chloride experiment solubility in water,which lead the leaching rate reach above 90%.For another hand,cuprous chloride formed in ammonium chloride experiment would transform into copper chloride and cuprous oxide in water.Cuprous oxide is insoluble in water,which decreased the leaching rate and lead leaching rate below 40%.