Journal of Chemistry / 2016 / Article / Tab 5 / Research Article
Chemical Modifications of Cassava Peel as Adsorbent Material for Metals Ions from Wastewater Table 5 Multiple quadratic mathematical equations obtained from the response surfaces for adsorption of Cd(II), Pb(II), and Cr(III) by adsorbents based on cassava peels, chemically modified and in natura .
Adsorbents Equations Cd M. in natura = 2.31392 − 0.00389216 + 0.00000183 + 0.0994207 − 0.00765268 − 0.000025750.970 M. H2 O2 = 2.22661 − 0.00391300 + 0.00000179 + 0.1135094 − 0.010198 − 0.00000212310.979 M. H2 SO4 = 2.09311 − 0.00367333 + 0.00000169 + 0.117596 − 0.0099065 − 0.000010225670.969 M. NaOH = 2.49556 − 0.00426238 + 0.00000195 + 0.106341 − 0.01022994 − 0.000004130330.969 Pb M. in natura = 2.42402 − 0.00410920 + 0.00000188 + 0.091384 − 0.00873871 − 0.000003921860.973 M. H2 O2 = 2.40349 − 0.00408627 + 0.00000186 + 0.090141 − 0.0092527 + 0.00000223040.975 M. H2 SO4 = 2.20750 − 0.00386993 + 0.00000182 + 0.108006 − 0.008937 − 0.00001720720.969 M. NaOH = 2.44355 − 0.00408057 + 0.00000187 + 0.0706209 − 0.006958 − 0.00000147710.974 Cr M. in natura = 2.60020 − 0.00422655 + 0.00000173 + 0.04990993 − 0.015409 + 0.000084152630.964 M. H2 O2 = 2.49313 − 0.00414079 + 0.00000176 + 0.08114590 − 0.015967 + 0.000056364270.965 M. H2 SO4 = 2.46274 − 0.00418541 + 0.00000178 + 0.10776064 − 0.0177875 + 0.00005228460.977 M. NaOH = 2.92410 − 0.00392245 + 0.00000163 − 0.149982207 + 0.005562 + 0.000067384930.986
= adsorbent mass (mg); = pH of the contaminant solution; = adsorbed quantity (mg g−1 ).