Variable Langmuir  isotherm model  parameter Friendlier isotherm model  parameter
qmax KL RL r2 KF n r2
Temperature
30°C 3.83 9.01 0.0024 0.991 4.92 17.24 0.912
40°C 4.26 7.04 0.0016 0.995 4.87 20.40 0.935
50°C 4.74 6.01 0.0033 0.975 4.85 29.41 0.946
60°C 5.02 5.53 0.0036 0.997 4.79 35.71 0.949
pH
5 3.61 1.091 0.0179 0.986 5.86 5.81 0.93
6 3.89 5.025 0.0039 0.995 4.94 14.92 0.87
7.5 4.56 13.69 0.0014 0.999 4.98 7.93 0.68
8 4.51 17.01 0.0011 0.945 5.10 13.69 0.90
9 3.11 0.245 0.0751 0.966 5.49 6.66 0.91
Adsorbent particle  size (mm)
0.150 4.56 7.191 0.0166 0.988 4.88 7.85 0.90
0.355 3.79 9.225 0.0123 0.985 4.91 10.96 0.89
0.5 3.56 14.69 0.0030 0.999 4.99 12.93 0.75
2.0 2.51 19.41 0.0022 0.965 5.22 13.69 0.80
Adsorbent dose (mg)
0.5 4.61 3.088 0.0109 0.976 5.75 8.83 0.89
1.0 3.39 6.045 0.0059 0.995 5.31 10.94 0.90
1.5 2.46 10.69 0.0034 0.998 4.98 11.95 0.88
2.0 1.9 14.01 0.0023 0.977 5.01 13.69 0.92
Adsorbate concentration (mg/l)
50 3.85 6.650 0.0199 0.986 5.80 12.81 0.91
75 3.78 5.760 0.0133 0.993 4.98 14.95 0.90
100 4.11 10.65 0.0083 0.998 5.22 17.22 0.88
125 3.51 16.09 0.0045 0.985 5.10 20.69 0.85
150 3.03 21.24 0.0013 0.976 5.21 25.65 0.91
Table 1: Langmuir and Freundlich isotherm constants for adsorption of MB onto DPF.