Citric　acid　modified　mixed　hardwoods　powder　(CMH)　was　prepared　as　a　biosorbent　to　remove　copper　ions　and　methylene　blue　(MB)　from　aqueous　solution　by　batch　techniques.　FT-IR　and　XRD　were　used　to　characterize　the　biosorbent.　The　effects　of　initial　pH　value,　biosorption　temperature,　contact　time,　and　initial　adsorbate　concentration　on　the　biosorption　capacities　and　adsorptivity　of　Cu2+　and　MB　onto　CMH　were　investigated.　The　results　showed　that　CMH　exhibited　excellent　biosorption　characteristics　for　Cu2+　and　MB.　The　maximal　biosorption　capacity　of　Cu2+　and　MB　onto　CMH　was　165.0　and　237.4　mg/g　at　20　C,　respectively.　The　biosorption　kinetics　studies　indicated　that　Cu2+　and　MB　biosorption　followed　the　pseudo-second-order　model.　The　biosorption　may　be　controlled　by　external　intraparticle　diffusion　mass　transfer　during　the　whole　biosorption　process.　Furthermore,　the　biosorption-equilibrium　can　be　well　described　by　Langmuir　and　Freundlich　isotherm　models.　©　2014　American　Chemical　Society.