The removal of dyes from wastes has been the object of many researches in the past few years because of the potential toxicity of dyes and visibility problems. Conventional tertiary treatment techniques are having technical and/ or economical constrains. In the present investigation the potential use of wheat bran (an agricultural waste) as low cost biosorbent for removal of methyl red from water was studied. For this purpose a three-level three-factor fractional factorial Box-Behnken Design

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... D) of Response Surface Methodology (RSM) which leads to only 15 sets of sorption runs was conducted to study the influence of pH, initial metal ion concentration and temperature and their interactions on dye removal. The pH had negative and temperature and concentration had positive effect on uptake of dye. Very high value of regression coefficient (R-Sq = 99.8%) indicates an excellent evaluation of the experimental data by second-order polynomial regression model. The maximum removal of methyl red (91.5181 mg/g) was predicted using contour and optimization plots and can be achieved at pH 2.0, initial metal ion concentration 300 mg/L and temperature 40 °C.