Engineered Geomedia Kaolin Clay-Reduced Graphene Oxide-Polymer Composite for the Remediation of Olaquindox from Water.

Globally, there is an upsurge in the use of unregulated veterinary pharmaceuticals with enhanced release into the environment, resulting in water pollution, which is difficult to remediate. To address this issue, we synthesized and characterized highly hydrophobic three-dimensional ordered engineered geomedia with multiple channels. Kaolin clay (K) was functionalized with either graphene oxide (GO) synthesized via Tour's method or reduced GO in situ with covalently linked methoxyether polyethylene glycol (GO-PEG) using a simple and easily scalable amidation reaction.

Covalently linked graphene oxide/reduced graphene oxide-methoxylether polyethylene glycol functionalised silica for scavenging of estrogen: Adsorption performance and mechanism.

Water pollution by pharmaceuticals is a global issue and its remediation is important. To overcome this, we synthesised super hydrophobic nanoporous 3-dimensional ordered nanomaterials with multi-functional binding chemistry for highly efficient adsorption of estrogen (17β-estradiol). Graphene oxide (GO) was synthesised via Tours method and methoxylether polyethylene glycol (mPEG) was covalently introduced onto GO surface via facile amidation mild process to give GO-mPEG.

Clean application of magnetic biomaterial for the removal of As (III) from water.

Magnetite-coated pine cone biomass was successfully synthesized, characterized, and its interaction with As (III) in water evaluated in order to apply it as an efficient adsorbent. Transmission electron microscope, scanning electron microscope, and imaging studies revealed that spherical magnetite particles were evenly distributed over the pine cone surface. Adsorption studies showed that the optimum pH of As (III) adsorption was 8 and that Fe (III) leaching was negligible at this pH.

Facile microwave synthesis of pine cone derived C-doped TiO for the photodegradation of tetracycline hydrochloride under visible-LED light.

Pine cone derived carbon was doped into TiO via a facile microwave procedure at different powers, different from other conventional synthesis methods. The materials were adequately characterized and applied in the photodegradation of 5 mg/L tetracycline hydrochloride (TA) under visible-LED light. The XRD results showed that all materials exist as both anatase and rutile phase.

Degree of time dependency of kinetic coefficient as a function of adsorbate concentration; new insights from adsorption of tetracycline onto monodispersed starch-stabilized magnetic nanocomposite.

The realization that the observed kinetic coefficient (k) varies with time in most real-time adsorption system, as against the constant value conceived in the most widely-applied adsorption kinetic models, have attracted much attention in recent time. Understanding the factors that control the extent/degree of time dependency (otherwise known as fractal-like kinetics), is therefore central in taking manipulative advantage of this phenomenon in critical adsorption applications. This study therefore deployed non-fractal-like and fractal-like kinetic approach to study the adsorption of tetracycline on monodispersed starch-stabilized magnetite nanocomposite (MSM).

Intraparticle diffusion process for lead(II) biosorption onto mansonia wood sawdust.

The overall biosorption rate of lead(II) onto mansonia wood sawdust has been determined. Kinetic modeling revealed that pseudo-second-order kinetics described the experimental data fully while pseudo-first kinetics followed for only 5 min. Ion-exchange constant, S, was similar to the pseudo-first-order rate constant, k(1), indicating that ion-exchange is important only in the first 5 min.

Equilibrium studies of copper ion adsorption onto palm kernel fibre.

The equilibrium sorption of copper ions from aqueous solution using a new adsorbent, palm kernel fibre, has been studied. Palm kernel fibre is obtained in large amounts as a waste product of palm oil production. Batch equilibrium studies were carried out and system variables such as solution pH, sorbent dose, and sorption temperature were varied.

Effect of temperatures and pH on methyl violet biosorption by Mansonia wood sawdust.

In this study, the effect of temperature on the equilibrium biosorption of methyl violet dye from aqueous solution using Mansonia wood sawdust was studied. The equilibrium biosorption data were analyzed using three widely applied isotherm models; Langmuir, Freundlich and Redlich-Peterson isotherm. The fit of three linear Langmuir isotherm forms, the Freundlich isotherm, and the Redlich-Peterson isotherm were determined using linear and the non-linear methods.

Effect of pH on cadmium biosorption by coconut copra meal.

Biosorption of cadmium ion by coconut copra meal, an agricultural waste product was investigated as a function of initial solution pH and initial cadmium concentration. Pseudo-second-order kinetic analyses were performed to determine the rate constant of biosorption, the equilibrium capacity, and initial biosorption rate. Cadmium biosorption by copra meal was found to be dependent on the initial solution pH and initial cadmium concentration.

Kinetic studies of copper ion adsorption on palm kernel fibre.

Palm kernel fibre is a common agricultural waste in West Africa and its use as an adsorbent for the removal of copper ions from aqueous solution has been studied. Batch kinetics studies were carried out based on the assumption of the pseudo-second-order kinetic model, which was developed to predict the rate constant of adsorption, the equilibrium adsorption capacity and initial adsorption rate with the effect of initial copper concentration and reaction temperature. A comparison was made of the linear least-squares method and a trial-and-error non-linear method of the pseudo-second-order kinetic model for the adsorption of copper onto palm kernel fibre.

Pseudo-second-order model for lead ion sorption from aqueous solutions onto palm kernel fiber.

The sorption of lead ion onto palm kernel fiber was studied by performing batch kinetic sorption experiments. The batch sorption model, based on a pseudo-second-order mechanism, was applied to predict the rate constant of sorption, the equilibrium capacity and the initial sorption rate with the effects of the initial solution pH and fiber dose. Equilibrium concentrations were evaluated with the equilibrium capacity obtained from the pseudo-second-order rate equation.

Effects of calcium competition on lead sorption by palm kernel fibre.

The kinetics of sorption of a mono-solute of lead ions and of a bi-solute of lead and calcium ions onto palm kernel fibre was investigated in a batch system. The experimental data were analysed based on an intraparticle diffusion equation and a pseudo-second-order mechanism, in both the mono- and bi-solute sorption systems, in order to predict the rate constant of sorption, the equilibrium capacity, and the initial sorption rate. The results indicate that the sorption mechanism is described by a pseudo-second-order equation.