Study of equilibrium, kinetic and thermodynamic parameters about methylene blue adsorption onto natural zeolite

Anionic and Cationic Dyes Removal from Aqueous Solutions by Adsorption onto Synthetic Mg/Al Hydrotalcite-Like Compound

“…3 results reveal that the adsorption is fast in the initial 30 min; however it gradually becomes slower with passage of time reaching equilibrium in about 100 min. From this result, it can be said that kinetics of removal efficiency three investigated dyes were formed in two phases: first, an initial rapid phase where the adsorption of dye molecules was fast and instantaneous, and the second phase was a slow stage in which the contribution to the total reactive dyes removal efficiency was relatively small, and finally the removal of both reactive dyes reached equilibrium [22]. The faster adsorption, which occurred in the initial stage, may be associated with the existence of large numbers of vacant adsorption sites on the surface.…”

Organic xenobiotics removal in constructed wetlands, with emphasis on the importance of the support matrix

“…The high ion exchange capacity of zeolites, their extensive porosities and specific surface areas, as well as their relatively cheap prices, make natural zeolites attractive adsorbents [208][209][210][211][212][213][214][215][216][217][218][219][220][221][222]. However, synthetic zeolites are also widely tested, especially because through synthesis a useful control can be obtained over the Si/Al ratio in the zeolite composition.…”

Effect of Process Factors on the Adsorption of MB Dye Using Adenia Lobata Fiber

“…7 shows that the linear plot did not pass through the origin which indicated that the intra particle diffusion was not only the rate controlling step and the boundary layer diffusion controlled the adsorption to some extent [18]. This deviation may be due to the difference in mass transfer rate in the initial and final stage of adsorption [17], [19]. Equally, its R 2 value of 0.9876, which is very close to 1.0 further confirm that the data fit well with the model.…”

“…The second portion is the gradual stage of adsorption which is the intra particle diffusion. If the plot of qt versus t 1/2 is linear and passed through the origin, then the intra particle diffusion is the rate-controlling step [17]. The third portion is the final equilibrium stage in which the intra particle diffusion starts to slow down due to the extremely low dye concentration left in the solution [18].…”