Radiation induced graft polymerization of glycidyl methacrylate onto sepiolite

Preparation and Performance Study of Boron Adsorbent from Plasma-Grafted Polypropylene Melt-Blown Fibers

In this study, the plasma graft polymerization technique was used to graft glycidyl methacrylate (GMA) onto polypropylene (PP) melt-blown fibers, which were subsequently aminated with N-methyl-D-glucamine (NMDG) by a ring-opening reaction, resulting in the formation of a boron adsorbent denoted as PP-g-GMA-NMDG. The optimal conditions for GMA concentration, grafting time, grafting temperature, and the quantity of NMDG were determined using both single factor testing and orthogonal testing. These experiments determined the optimal process conditions to achieve a high boron adsorption capacity of PP-g-GMA-NMDG. Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersion spectrum analysis (EDS), and water contact angle measurements were performed to characterize the prepared adsorbent. Boron adsorption experiments were carried out to investigate the effects of pH, time, temperature, and boron concentration on the boron adsorption capacity of PP-g-GMA-NMDG. The adsorption isotherms and kinetics of PP-g-GMA-NMDG for boron were also studied. The results demonstrated that the adsorption process followed a pseudo-second-order kinetic model and a Langmuir isothermal model. At a pH of 6, the maximum saturation adsorption capacity of PP-g-GMA-NMDG for boron was 18.03 ± 1 mg/g. In addition, PP-g-GMA-NMDG also showed excellent selectivity for the adsorption of boron in the presence of other cations, such as Na+, Mg2+, and Ca2+, PP-g-GMA-NMDG, and exhibited excellent selectivity towards boron adsorption. These results indicated that the technique of preparing PP-g-GMA-NMDG is both viable and environmentally benign. The PP-g-GMA-NMDG that was made has better qualities than other similar adsorbents. It has a high adsorption capacity, great selectivity, reliable repeatability, and easy recovery. These advantages indicated that the adsorbents have significant potential for widespread application in the separation of boron in water.

Synthesis, Characterization, and Adsorptive Characteristics of Radiation-Grafted Glycidyl Methacrylate Bamboo Fiber Composites

In the present study, a biosorbent was prepared through the radiation-induced graft polymerization (RIGP) technique by using a glycidyl methacrylate (GMA) monomer. Functionalized bamboo materials were used for grafting. The grafting percentage (G %) of GMA on bamboo fibers was assessed based on the optimization of the absorbed dose and concentration of the monomer. The chemical modification of the polymerized product into the sulfonated form of the grafted biopolymer was carried out by using sodium sulfite solution. The modification of the biopolymer at various stages was analyzed by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. By performing scanning electron microscopy (SEM), the morphological changes of the prepared biopolymer were analyzed. The temperature stability of the synthesized material was assessed by the thermogravimetric analysis (TGA) technique. The prepared sulfonated biosorbent was used in the batch adsorption study for the uptake of copper. We examined a variety of variables, including pH, adsorbent dosage, and time. The adsorption kinetics were studied using pseudo-first-order (PFO) and pseudo-second-order (PSO) models. Adsorption isotherms and thermodynamic parameters were also applied to study the adsorption capacity of the biosorbent. The maximum copper adsorption capacity was found to be 198 mg g-1 from the Langmuir isotherm. Copper adsorption followed PSO kinetics (R2 = 0.999). This inexpensive and eco-friendly biosorbent removed 96% of copper ions from the solution.

Radiation-Grafting on Polypropylene Copolymer Membranes for Using in Cadmium Adsorption

Graft copolymerization has been a popular technique in recent years for adding different functional groups to polymers. In our research, polypropylene (PP) films are grafted with acrylonitrile (An) and acrylic acid (AAc) monomers to make them hydrophilic while retaining their mechanical qualities. Gamma radiation is used in this approach to establish active spots on an inert polymer that are appropriate for adding monomers radicals to form grafts, a procedure that is extremely difficult to perform using normal chemical processes. The graft parameters are investigated in order to acquire the highest percentage of graft. FTIR (Fourier transform infrared spectroscopy) spectra are used to analyze the grafting of AAc and An. SEM (scanning electron microscopy) and XRD (X-ray diffraction) micrographs are used to validate them. The specimens' tensile strength and hardness are measured and contrasted with blank PP films. Measurements are made of the effects of grafting on the tensile strength and elongation of the films, and a crucial grafting degree is established in order to preserve these properties. Water uptake is measured to adapt the copolymer to water treatment, and thermal behavior TGA (thermal gravimetric analysis) and DSC (diffraction scanning calorimeter) of the produced copolymer were performed. The elimination of cadmium was verified by an atomic absorption spectrophotometer (AAS) under different conditions of pH, time, and degree of grafting.

A novel utilization of raw sepiolite: preparation of magnetic adsorbent directly based on sol-gel for adsorption of Pb(II)

The constraints of industrial separation technology for low grade sepiolite greatly limit the development and utilization of these potential resources. In this work, a novel sepiolite adsorbent loaded with copper ferrite was prepared by sol-gel method to remove Pb(II) from wastewater. The effects of various factors on Pb(II) removal ratio were investigated. The maximum adsorption capacities at 293, 313, and 333 K were 1285.32, 1325.45, and 1390.54 mg/g, respectively. The adsorption of Pb(II) by magnetic sepiolite was a spontaneous endothermic process. Besides, the adsorption process followed Langmuir isothermal adsorption model and pseudo-second-order kinetic model. The main adsorption mechanism of Pb(II) removal was electrostatic attraction, ion exchange, and surface complexation. The improvement of Pb(II) absorption indicated that the efficient removal of Pb(II) can be realized by phosphate groups introduced in the preparation process and the carbonate groups contained in gangue minerals.

Multivariate optimization of removing of cobalt(II) with an efficient aminated-GMA polypropylene adsorbent by induced-grafted polymerization under simultaneous gamma-ray irradiation

Nowadays, radiation grafting polymer adsorbents have been widely developed due to their advantages, such as low operating cost, high efficiency. In this research, glycidyl methacrylate monomers were grafted on polypropylene polymer fibers by simultaneous irradiation of gamma-ray with a dose of 20 kGy. The grafted polymer was then modified using different amino groups and tested for adsorption of cobalt ions in an aqueous solution. Finally, the modified polymer adsorbent with a high efficiency for cobalt ions adsorption was synthesized and tested. Different modes of cobalt ions adsorption were tested in other adsorption conditions, including adsorption contact time, pH, different amounts of adsorbent mass, and different concentrations of cobalt ions solution. The adsorbent structure was characterized with FT-IR, XRD, TG and SEM techniques and illustrated having an efficient grafting percentage and adsorption capability for cobalt removing by batch experiments. The optimum conditions were obtained by a central composite design: adsorbent mass = 0.07 g, initial concentration = 40 mg/L, time = 182 min, and pH = 4.5 with ethylenediamine as a modified monomer and high amination percentage. Kinetics and equilibrium isotherms observation described that the experimental data followed pseudo-second-order and Langmuir models, respectively. The maximum adsorption capacity from Langmuir isotherm capacity is obtained equal to 68.02 mg/g.