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Importance of recycling of ferrous scrap has been recognized,due to the limitation of sound iron ore/ coal and demand for lowering CO2 gas emission generated from blast furnace ironmaking process and oxygen steelmaking process.One of the serious problems of using the ferrous scrap is introduction of tramp elements such as Cu in the ferrous scrap.Once the scrap melts down to molten steel,removal of Cu from the molten steel is very difficult to achieve by conventional oxidation refining process,because of its low affinity to the oxygen.Therefore,it has long been sought to develop a new technology to remove Cu from the molten steel.A number of suggestions have been proposed for copper removal process;sulfide flux refining,vacuum distillation,low melting point bath,and chlorination.However,some of the suggestions show relatively low degrees of removal as well as some innate disadvantages of the process.In this presentation,those proposed processes are reviewed and their pros and cons are discussed.Further considerations in those processes are suggested.Furthermore,on-going research efforts in the authorsIaboratory are presented.One of the efforts is a proposal of Cu removal via an oxysulfide smelting process.The basic concept of this approach is that the steel scrap containing Cu is melted in an oxysulfide solvent at low temperature where the solvent is in liquid state,and the metallic iron is attempted to be reduced out of the solvent,leaving most of the Cu in the by a proper control of oxygen and sulfur potentials in the system.Some of fundamental result for the proposal is presented.The other effort is a Cu evaporation refining.This proposal is based on the preferential evaporation of Cu from the molten steel.One of advantages of this refining is that no harmful by-products such as slag is not generated.Evaporation removal is applicable not only form Cu but also for other kind of tramp element such as Sn.The present status of those investigations and further points to be improved are discussed.