In this chapter, the low-cost, biodegradable absorbents are developed for
wastewater treatment. At first, the modification of the procured nano ZSM-5 is
executed by means of dealumination and ion exchange process to have de-laminated
(D-ZSM-5), Cu-ZSM-5 and Fe-ZSM-5. Furthermore, cellulose nanofibrils (CNFs) are
mixed with modified zeolites with varying concentrations (20 and 80 wt%) used for the
fabrication of innovative composite films ((D-ZSM-5, Cu-ZSM-5 and Fe-ZSM-5).
FTIR, XRD, BETCO2, TGA, and SEM type of characterization techniques are used for
the analysis of composites. The prepared composite films are exploited for cationic
Rhodamine B (Rh6B) and anionic Reactive Blue 4 (RB4) dye elimination by the
activity of adsorption. The effect of contact time, initial dye concentration and pH on
the dyes’ adsorption in aqueous buffer solutions is examined. The equilibrium
adsorption data are estimated using Langmuir, Freundlich, and Temkin isotherm
models. Langmuir isotherm is deemed to be the best-fitting model and the process
(kinetics and mechanism) follows pseudo-second-order kinetics, yielding an uppermost
adsorption capacity of 34 mg/g, and 16.55 mg/g which is comparable to plane CNF
(8.7mg/g) and (0.243mg/g) for cationic Rh6B dye and anionic RB4 dye respectively.
Maximum dye removal is observed for a higher amount of (80% ZSM-5) film. The
study reveals that ZSM-5/ CNFs films can potentially be used for the removal of
cationic and anionic dyes.
Keywords: Adsorption, Adsorption kinetics, BET, Cellulose nanofibrils, Dealumination, Dye modification, Freundlich, FTIR, Ion exchange, Isotherm models, Langmuir, Nanocomposites, Pseudo-first and second order, Reactive blue, Rhodamine B dye, Temkin, TGA, XRD, ZSM-5 zeolite.
