Table 2. Kinetic model parameters for DY27 biosorption onto corncob at different solution pH levels.
| Solution pH | 1.5 | 2.0 | 2.5 | 3.0 | 4.0 | 5.0 | 6.0 |
| qe exp [mg g-1] | 35.1551 ± 0.8815 | 28.4783 ± 0.4683 | 20.5694 ± 0.4657 | 12.6606 ± 0.9735 | 6.900 ± 0.9896 | 4.2121 ± 0.79 | 1.5235 ± 0.08962 |
| Pseudo-first-order | |||||||
| qe1 | 32.52 ± 1.0 | 25.65 ± 0.92 | 18.58 ± 0.66 | 11.51 ± 0.58 | 8.052 ± 0.409 | 4.716 ± 0.215 | 1.437 ± 0.059 |
| k1 | 0.647 ± 0.0689 | 1.279 ± 0.204 | 1.222 ± 1.191 | 1.115 ± 0.8759 | 1.020 ± 0.2164 | 1.075 ± 0.2047 | 1.152 ± 0.1893 |
| r2 | 0.9662 | 0.9238 | 0.9269 | 0.8724 | 0.8726 | 0.8950 | 0.9486 |
| ASS | 197.5 | 254.7 | 129.6 | 95.13 | 45.04 | 12.73 | 0.5502 |
| Sy.x | 2.008 | 2.280 | 1.626 | 1.393 | 0.9587 | 0.5098 | 0.1203 |
| AIC | 75.57 | 88.52 | 54.08 | 38.31 | 0.1721 | -64.26 | -164.8 |
| Pseudo-second-order | |||||||
| qe2 | 35.62 ± 0.87 | 28.02 ± 0.62 | 20.35 ± 0.46 | 12.68 ± 0.61 | 8.883 ± 0.394 | 5.195 ± 0.203 | 1.579 ± 0.061 |
| k2 | 0.0259 ± 0.0031 | 0.06507 ± 0.0084 | 0.08452 ± 0.0109 | 0.1197 ± 0.03242 | 0.1577 ± 0.382 | 0.2840 ± 0.0616 | 0.9573 ± 0.1953 |
| r2 | 0.9831 | 0.9794 | 0.9795 | 0.9162 | 0.9301 | 0.9443 | 0.9664 |
| ASS | 98.66 | 68.92 | 36.40 | 62.51 | 24.70 | 6.759 | 0.3595 |
| Sy.x | 1.419 | 1.186 | 0.8619 | 1.129 | 0.7100 | 0.3714 | 0.09727 |
| AIC | 40.16 | 21.86 | -10.69 | 16.89 | -30.46 | -96.56 | -181.8 |
| Elovich | |||||||
| BE | 0.1921 ± 0.0226 | 0.2794 ± 0.0298 | 0.3802 ± 0.0403 | 0.5944 ± 0.089 | 0.8387 ± 0.1064 | 1.443 ± 1.3508 | 4.581 ± 0.771 |
| AE | 157.1 ± 74.14 | 448.1 ± 249.6 | 290 ± 157.1 | 140.9 ± 102.79 | 87.40 ± 52.73 | 54.80 ± 33.94 | 12.71 ± 9.506 |
| r2 | 0.9181 | 0.9313 | 0.9316 | 0.8710 | 0.9035 | 0.9016 | 0.8806 |
| ASS | 479.0 | 229.8 | 121.2 | 96.22 | 34.12 | 11.94 | 1.279 |
| Sy.x | 3.126 | 2.165 | 1.573 | 1.401 | 0.8344 | 0.4936 | 0.1835 |
| AlC | 120.7 | 83.27 | 50.67 | 38.88 | -13.99 | -67.54 | -131.0 |
| Intraparticle diffusion | |||||||
| kid | 3.545 ± 0.887 | 2.523 ± 0.719 | 1.852 ± 0.52 | 1.18 ± 0.343 | 0.8446 ± 0.2268 | 0.4862 ± 0.1354 | 0.1504 ± 0.505 |
| c | 13.76 ± 2.87 | 13.97 ± 2.32 | 9.961 ± 1.68 | 5.951 ± 1.109 | 4.053 ± 0.733 | 2.415 ± 0.438 | 0.6664 ± 0.1654 |
| r2 | 0.5688 | 0.5038 | 0.5117 | 0.4941 | 0.5340 | 0.5157 | 0.4887 |
| ASS | 2521 | 1659 | 865.7 | 377.3 | 164.7 | 58.76 | 5.478 |
| Sy.x | 7.173 | 5.819 | 4.203 | 2.775 | 1.833 | 1.095 | 0.3797 |
| AIC | 205.4 | 184.1 | 150.9 | 108.6 | 66.30 | 13.73 | -72.86 |
| Fractional power | |||||||
| kfp | 18.41 ± 1.53 | 17.56 ± 1.06 | 12.57 ± 0.77 | 7.588 ± 0.598 | 5.211 ± 0.372 | 3.086 ± 0.222 | 0.9003 ± 0.0932 |
| v | 0.1851 ± 0.0305 | 0.1465 ± 0.0234 | 0.1495 ± 0.0237 | 0.1563 ± 0.0301 | 0.1612 ± 0.0271 | 0.1580 ± 0.0276 | 0.1649 ± 0.0377 |
| r2 | 0.8392 | 0.8669 | 0.8949 | 0.8665 | 0.8438 | 0.8371 | 0.7984 |
| ASS | 939.9 | 445.2 | 221.4 | 236.8 | 55.21 | 19.76 | 2.160 |
| Sy.x | 4.380 | 3.014 | 2.194 | 2.198 | 1.061 | 0.6350 | 0.2384 |
| AIC | 155.1 | 117.0 | 79.93 | 84.81 | 10.56 | -41.85 | -110.1 |