Concentration pH Absorbance RPM Contact time 2 03 4 0 2046 100 60 229 4 0 2253 100 90 1 79 4 0 184 165 60 2 23 4 0 2204 165 90 198 5 0 1796 100 60 0.91 5 0.0868 100 90 64 5 0 0614 165 60 0.06 5 0.006 165 90 119 6 0 1276 100 60 1.37 6 0.1452 100 90 167 6 0 1733 165 60 1.87 6 0.1908 165 90 0.05 7 0 0045 100 60 0 7 0.0003 100 90 0 11 7 0 0107 165 60 0.19 7 0.0184 165 90

(a): For lead with eggshell.

Concentration pH Absorbance RPM Contact time 2.92 4 0 2299 100 60 2.79 4 0.2197 100 90 3 4 0 2366 165 60 116 4 0 249 165 90 2.03 5 0 2046 100 60 229 5 0.2253 100 90 1.79 5 0.184 165 60 223 5 0.2204 165 90 113 6 0 2469 100 60 305 6 0 2402 100 90 115 6 0 2478 165 60 3.38 6 0.2665 165 90 1.19 7 0 1276 100 60 1.37 7 0.1452 100 90 1.67 7 0 1733 165 60 1.87 7 0.1908 165 90

(b): For lead with banana peel.

Concentration pH Absorbance RPM Contact time 3 35 4 0 2441 100 60 2.63 4 0.1912 100 90 3 24 4 0 2357 165 60 2.58 4 0.1881 165 90 1.96 5 0 1588 100 60 1.39 5 0.113 100 90 2 08 5 0 1686 165 60 112 5 0.0908 165 90 2 21 6 0 1607 100 60 2.23 6 0.1621 100 90 2.76 6 0 2006 165 60 1.97 6 0.1432 165 90 2.36 7 0 1909 100 60 1.74 7 0.141 100 90 248 7 0 2007 165 60 1.85 7 0.1501 165 90

(c): For lead with pumpkin.

Table 2: Table for lead with parameters.