Table 4: Kinetic constants and correlation coefficients for sorption of ammonium using natural and modified kaolinite sorbents at different initial concentrations.

Sorbents , (mg·L−1) (mg·g−1) Pseudo-first-orderPseudo-second-order Intraparticle diffusionElovich kinetic model
(mg·g−1) (mg·g−1)

K1002.65 6.330.9145 2.820.99472.092.482.77 0.1710.9811
2007.88 10.220.8632 8.470.99874.5529.3026.490.0710.9598
50018.58 21.220.9335 18.870.997112.7739.2433.250.0280.9824

AHK1004.440.010418.170.9342 4.520.99791.6427.3847.640.1490.9554
20010.230.023920.330.9424 10.700.99971.9480.21100.080.1440.9514
50025.650.021435.560.9219 24.560.99970.67684.44234.290.1380.9538

HK1004.89 24.170.8888 5.040.99991.4935.05196.370.1600.9645
2009.93 25.100.9205 9.520.99970.40796.45172.180.14209656
50022.760.019844.80.9389 22.980.99954.58198.96302.190.0690.9654

HAK1004.750.016115.10.8971 4.870.99971.8030.0265.970.1610.9755
2009.550.010314.00.8935 9.710.99982.3773.6975.010.1350.9887
50023.16 64.80.8773 23.250.99923.04197.28221.180.0610.9745