The　comparative　study　was　carried　out　for　the　decolorization　of　three　kinds　of　dyes:　azo　dye,　Reactive　Brilliant　Red　K-2G　(RBR);　anthraquinone　dye,　Reactive　Brilliant　Blue　KN-R　(RBB);　and　triphenylmethane　dye,　Malachite　Green　(MG)　from　aqueous　solution　by　zero-valent　iron　(ZVI)　as　an　effective　reductant.　ZVI　was　synthesized　with　a　modified　method　of　reduction　in　liquid　phase,　in　which　the　macromolecule　stabilizer　polyvinylpyrrolidone　was　added.　The　effects　of　solution　pH.　ZVI　dosage　and　initial　dye　concentration　on　the　decolorization　were　investigated.　The　results　showed　that　pH　value　had　little　effect　on　dye　decolorization.　With　increasing　dosage　of　ZVI,　decolorization　efficiency　increased,　but　reduction　capacity　and　reaction　time　showed　descending　trends.　High　decolorization　efficiency　(95.74-99.22%)　was　achieved　within　2　min　for　698.24　mg/L　for　RBR,　10　min　for　691.69　mg/L　for　RBB　and　30　min　for　686.10　mg/L　for　MG　at　optimal　pH.　The　first-order　kinetic　model　was　found　to　fit　the　experimental　data　well.　The　UV-vis　spectra　and　FTIR　spectra　analysis　indicated　that　chromophores　of　dyes　were　destroyed　and　some　functional　groups　such　as　amino　and　aromatic　ring　were　transformed　in　the　decolorization　process.　ZVI　was　proved　to　be　a　universal　and　efficient　reductant　for　rapid　decolorization　of　the　three　dyes.　(C)　2011　Elsevier　B.V.　All　rights　reserved.