The　removal　of　copper　ions　by　magnetic　Fe3O4/carbon　nanotube　(CNT)　composite　adsorbents,　prepared　by　co-precipitation　method,　in　aqueous　solution　has　been　investigated.　The　influence　of　magnetite　loading　(35.5-64.1　wt.%)　onto　oxidized　CNT　support　on　the　adsorption　capacity　and　regeneration　efficiency　is　investigated.　The　adsorption　isotherms　of　Cu2+　ions　are　well　characterized　by　Langmuir,　Freundlich,　and　Dubinin-Radushkevich　models　within　the　temperature　range　of　303-323　K.　The　decoration　of　magnetic　Fe3O4　significantly　enhances　the　removal　efficiency,　equilibrium　rate　constant,　and　adsorption　capacity,　as　analyzed　by　these　models.　The　appropriate　loading　of　magnetite　nanoparticles　on　the　CNT　supports　not　only　increases　adsorption　capacity　but　also　facilitates　regeneration　efficiency.　Accordingly,　the　Fe3O4/CNT　composite　can　be　used　as　an　effective　adsorbent　for　rapid　removal　of　Cu2+　ions　from　aqueous　solution.　(C)　2017　Taiwan　Institute　of　Chemical　Engineers.　Published　by　Elsevier　B.V.　All　rights　reserved.