Factors Rice straw Dragon tree leaves X pH BD RF1 Average (%) RF2 Average (%) -1 -1 -1 31.00 48.38 -1 -1 1 61.99 67.63 -1 1 -1 72.78 76.06 -1 1 1 82.30 79.40 1 -1 -1 7.79 13.03 1 -1 1 28.09 35.32 1 1 -1 27.27 45.44 1 1 1 60.91 55.16

Table 2: Experimental factorial design results for Cd(II) biosorption(X: metal ion concentration, pH: hydrogen ion concentration, BD: biomass dose)