Hydrogel Based on Tricarboxi-Cellulose and Poly(Vinyl Alcohol) Used as Biosorbent for Cobalt Ions Retention

Abstract

A biomaterial based on poly(vinyl alcohol) reticulated with tricarboxi-cellulose obtained by TEMPO oxidation (OxC25) was used as a new biosorbent for Co(II) ions retention from aqueous solutions. The biosorption process of Co(II) ions was studied while mainly considering the operational factors that can influence it (i.e., biosorbent concentration, pH of the aqueous media, temperature and contact time of the phases). The maximum adsorption capacity was 181.82 mg/g, with the biosorption well fitted by the Langmuir model. The kinetic modeling of the biosorption process was based on certain models: Lagergreen (pseudo first order model), Ho (pseudo second order model), Elovich (heterogeneous biosorbent model), Webber–Morris (intraparticle diffusion model) and McKay (film diffusion model). The corresponding kinetic model suggests that this biosorption process followed a pseudo-second order kinetic model and was developed in two controlled steps beginning with film diffusion and followed by intraparticles diffusion.

Biosorbent Based on Poly(vinyl alcohol)–Tricarboxi-Cellulose Designed to Retain Organic Dyes from Aqueous Media

“…They were calculated based on Equation (3), as well as the relationships between the three parameters (4). Additionally, using the graphic representation lnK L = f(1/T) with R 2 = 0.993 ( Figure 9 ), the value of ΔH 0 and ΔS 0 were determined [ 63 , 78 ].…”

“…The specialized literature indicates various protocols for obtaining hydrogels based on 2,3,6 tricarboxy-cellulose ( Figure 2 a) and poly(vinyl alcohol) (PVA) ( Figure 2 b) [ 62 , 64 ]. The OxC25 hydrogel utilized as biosorbent in this investigation was made using the procedure and guidelines provided in our prior work [ 63 ].…”

“…Among the many models that describe the adsorption processes presented in the specialized literature, we selected three, considered more representative for the purpose pursued in our study [ 62 , 63 , 65 ]. Their general equations and the linearized forms are presented below: Freundlich (F) …”

“…Although it has poor mechanical strength, several elements that could increase it have been explored. Research has focused on specific natural polymers (cellulose and pullulan) in various concentrations, in the form of oxidized C6 derivatives, as important multifunctional components that could serve as crosslinking agents as well as agents for enhancing the hardening and stiffness properties of hybrid PVA hydrogels [ 52 , 53 , 60 , 61 , 62 , 63 ]. These biosorbents derived from natural resources can also be employed to successfully retain some heavy metal species from various aqueous systems.…”

Mn(II) Sorption on Stream Sediments Sampled in Manganese Mining Area: Dynamics and Mechanisms

“…where Q e (mg•g −1 )is the equilibrium value of adsorbed Mn(II), t (min) is the sorption time (min), k 1 (min −1 ) and k 2 (g•mg −1 ) are the pseudo primary and pseudo secondary rate constants, respectively. In the Elovich equation, a (mg•(g•min) −1 ) is the constant on the initial sorption rate, b constant is the surface coverage and chemical Intraparticle diffusion equation, k d (mg•(g•min 1/2 ) −1 ) is the rate constant for intraparticle diffusion, c is the intercept of the y-axis [28].…”