<p>Copper slag, generated during copper smelting and classified as a potentially harmful waste, is an important secondary resource. Copper slag has 41 wt.% iron content, which can meet the growing demand for iron and solve its handling problem. During iron recovery from copper slag, copper's influence must be considered. Excessive copper in iron can induce brittleness, limiting its applications to niche domains. To utilize the iron of copper slags, an oxidation modification-molten chlorination process was proposed to remove copper from copper slags. The methodology prioritizes copper elimination to prevent metallic impurity exceedance in ferrous products while suppressing iron volatilization, thereby enhancing iron retention in the tailings to facilitate subsequent extraction processes. After oxidative modification, the copper removal rate stabilized at 79.11%, while iron volatilization was significantly suppressed from 15.02% to 9.14%. Through experimental and kinetic analysis of the oxidation stage, results demonstrate that iron olivine undergoes complete oxidation and decomposition into iron oxides under oxygen atmosphere roasting, with an average apparent activation energy of 50.43&#xa0;kJ.mol⁻¹. The mechanism function for the iron oxidation process was the Avrami-Erofeev model (<i>n</i> = 1). Application of dual-mode theory to copper slag chlorination yielded the fundamental reaction rate relationship: <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\( J_{{{\text{CuCl}}}} = 2J_{{{\text{Cl}}_{2} }}^{\prime } = 2{\raise0.7ex\hbox{${D_{{{\text{Cl}}_{2} }} }$} \!\mathord{\left/ {\vphantom {{D_{{{\text{Cl}}_{2} }} } {\delta RT}}}\right.\kern-\nulldelimiterspace} \!\lower0.7ex\hbox{${\delta RT}$}}p_{{{\text{Cl}}_{2} }} \)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>J</mi> <mtext>CuCl</mtext> </msub> <mo>=</mo> <mn>2</mn> <msubsup> <mi>J</mi> <mrow> <msub> <mtext>Cl</mtext> <mn>2</mn> </msub> </mrow> <mo>′</mo> </msubsup> <mo>=</mo> <mn>2</mn> <mrow> <mpadded voffset="+0.7ex"> <msub> <mi>D</mi> <msub> <mtext>Cl</mtext> <mn>2</mn> </msub> </msub> </mpadded> <mspace width="-0.166667em" /> <mrow> <mfenced open="/"> <mphantom> <mpadded width="0pt"> <msub> <mi>D</mi> <msub> <mtext>Cl</mtext> <mn>2</mn> </msub> </msub> <mrow> <mi>δ</mi> <mi>R</mi> <mi>T</mi> </mrow> </mpadded> </mphantom> </mfenced> </mrow> <mspace width="-0.166667em" /> <mpadded voffset="-0.7ex"> <mrow> <mi>δ</mi> <mi>R</mi> <mi>T</mi> </mrow> </mpadded> </mrow> <msub> <mi>p</mi> <msub> <mtext>Cl</mtext> <mn>2</mn> </msub> </msub> </mrow> </math></EquationSource> </InlineEquation></p>