Ahmed M. Yousif

Synthesis of amine and thio chelating resins and study of their interaction with zinc(II), cadmium(II) and mercury(II) ions in their aqueous solutions

Chelate forming resins containing amino and thio groups have been prepared. The interaction of the obtained resins with Zn(II), Cd(II) and Hg(II) from their aqueous solutions was studied. The metal ion uptake behaviour and selectivity of the resins towards the metal ions were investigated by both batch and column methods. Hg(II) showed higher affinity towards the amino and the thio resins compared to Zn(II) or Cd(II). The mechanism of interaction between the resin and the studied metal ions could be explained on the basis of the formation of resin–metal complex in neutral conditions. In mediums acidified by HCl, the interaction of Hg(II) was interpreted to proceed via ion-exchange mechanism. Hg(II) could be separated from Cd(II) in acidic medium. The studied resins were regenerated using HNO3 or acidified thiourea. It was not recommended to use HCl for elution of Hg(II) from the loaded resins due to its affinity for interaction with resins via ion-exchange.

Studies on uptake behaviour of copper(II) and lead(II) by amine chelating resins with different textural properties

Glycidyl methacrylate resins with different ratios of divinylbenzene as cross-linking agent have been prepared. The textural properties such as density, porosity, pore area and pore diameter of the resins obtained were elucidated. The resins were anchored by chelating amino groups through the treatment with ethylenediamine (en). The amino group concentration on the resins was determined. The uptake behaviour of Cu(II) and Pb(II) from their aqueous solutions by the resins was studied. Both uptake capacity and selectivity of the resins towards the studied metal ions were discussed in terms of amino group concentration as well as the textural properties. The study indicated that metal-resin interaction proceeds via surface and diffusion mechanisms. The pH 5.8 found to be the most suitable for the uptake of the investigated metal ions. Copper was selectively separated from lead (using resin RI-en). The studied resins showed good durability and regeneration using HNO3.

Effect of Chain Length of Aliphatic Amines Immobilized on a Magnetic Glycidyl Methacrylate Resin towards the Uptake Behavior of Hg(II) from Aqueous Solutions

Abstract Magnetic resin particles with magnetite (Fe3O4) core and glycidyl methacrylate/divinylbenzene resin shell were prepared. The core‐shell particles obtained were immobilized with ethylenediamine, diethylenetriamine, or tetraethylenepentamine to give resins with names, R‐1, R‐2 and R‐3, respectively. These resins showed good magnetic properties and could be easily retrieved from their suspensions using an external magnetic field. The uptake values of resins towards Hg(II) were found to be 2.1, 3.2, and 4.8 mmol/g for resins R‐1, R‐2, and R‐3, respectively. The effect of chain length as well as the content of amine sites on the uptake behavior was studied at different temperatures. The values of kinetic and thermodynamic parameters of the uptake process were reported. These values reflected the effective role of amine type and chain length on both the rate of uptake and the maximum capacity of the resins. Moreover, the column studies showed that the longer the amine chain was the shorter was the critical bed height.

ADSORPTION OF MALATHION ON THERMALLY TREATED EGG SHELL MATERIAL

Thermally treated egg shell materials were prepared at different temperatures. The samples were investigated by means of FT-IR and thermogravimetric analysis (TGA). The adsorption behaviour of malathion on egg shell and its thermally treated samples was studied using batch method and gave uptake capacities up to 0.964 mmol/g. Adsorption kinetics as well as the adsorption isotherms were discussed. Regeneration of the loaded adsorbent beads towards the successive cycles was also clarified. The adsorption of malathion is maintained until the third cycle without a significant activity loss.

Preparation and Characterization of Modified Cellulose Adsorbents with High Surface Area and High Adsorption Affinity for Hg(II)

Cellulose was modified via chlorination using phosphorous oxychloride followed by functionalization with amine and thiol moieties. The obtained modified cellulose samples were investigated by means of FTIR, TGA, TEM, and nitrogen-adsorption surface area (BET). The BET measurements showed a remarkable increase in the surface area of Cell-N-S (477.7 m2/g) and Cell-N (706 m2/g). The resins gave an uptake capacities of 38 and 7.2mmol/g for Cell-N-S and Cell-N, respectively toward Hg(II) from its solutions. These values are considered much better compared with other reported resins. Regeneration of the resins was achieved effectively using acidified thiourea.

Efficient adsorption of Ag(І) and Au(ІІІ) on modified magnetic chitosan with amine functionalities

AbstractSodium tripolyphosphate (TPP) crosslinked magnetic chitosan adsorbent was prepared and immobilized with pentamine moieties. The adsorption behavior of the prepared adsorbent toward Ag(І) and Au(ІІІ) was studied at different experimental condition using batch and column methods. The maximum adsorption capacity was found to be 1.7 and 2.3 mmol g−1 for Ag(І) and Au(ІІІ), respectively. The mechanism of interaction between metal ion and adsorbent was found to proceed via complex formation and/or ion exchange. Kinetics and thermodynamic studies showed that the adsorption followed pseudo-second order with endothermic nature. The regeneration of the loaded resin was performed using 1.0 M acidified thiourea and was found to be 95–97%. The flow rate of 1.0 mL min−1 in column experiments was found to be the most preferable rate.

Fabrication of New Cellulose-Based Sorbents for Fast and Efficient Removal of Hazardous Al(III) Ions from Their Aqueous Solutions

Cellulose was used as a base polymer in two prepared resins when it was grafted by glycidyl methacrylate (GMA) then immobilized with 8-hydroxyquinoline by two different procedures. The resulting resins were characterized by infrared (IR) spectroscopy, thermogravimetric analysis (TGA), and nitrogen surface area measurements (BET). The two resins were used in the removal of hazardous Al(III) from their aqueous solutions. The present work discussed the preparation and the effect of spacer arms length used in the functionalization steps on the adsorption process. The resin with longer spacer arm showed faster kinetics compared with the other one toward Al(III) ion adsorption. Fast and efficient adsorption of hazardous Al(III) ions from drinking water by these resins indicates their applicability in water treatment applied field. Thermodynamic parameters were calculated for the studied resins and showed that they possess spontaneous exothermic nature. The regeneration efficiencies reached 90 ± 0.5% over three cycles using a mixture of 2 M HCl and 0.5 M HNO3. GRAPHICAL ABSTRACT

Efficient and Fast Adsorption of Phosphates and Sulphates on Prepared Modified Cellulose

Synthesis of modified cellulose (Cell-GTA) containing quaternary amine functionality was performed. The adsorbent was used to adsorb phosphate and sulphate anions at different experimental conditions using batch method. Kinetic and thermodynamic properties as well as the mechanism of interaction between studied anions and adsorbent were discussed. The adsorption behavior of the obtained samples showed high adsorption capacity as well as fast uptake toward studied anions in their solutions. The maximum adsorption capacities of and on Cell-GTA were found to be 1.88 and 3.68 mmol/g, respectively. Regeneration of the loaded adsorbents toward the successive reuse was also investigated. GRAPHICAL ABSTRACT

Rapid and Selective Adsorption of Rh(III) from its Solutions Using Cellulose-Based Biosorbent Containing Iminodiacetate Functionality

A new chelating biosorbent with iminodiacetate functionality was prepared. This biosorbent showed a powerful uptake behavior towards Rh(III) from its dilute solutions. The kinetic and thermodynamic characteristics of the uptake process were evaluated using the batch method. The recovery percentage value obtained is comparable to that of a commercial one with the same functionality (Chelest IRY) but with faster kinetics. Fast and selective adsorption of Rh(III) from Pd (II) and Pt(IV) during column experiments makes the resin promising in the field of Rh(III) recovery from the spent catalytic convertors. The adsorbed rhodium was recovered simply by burning the spent resin.

Fast and Efficient Uptake of Fe(III) from Aqueous Solutions Using Magnetic Functionalized Cellulose

Durable low-cost biosorbents possessing fast kinetics toward Fe(III) adsorption from aqueous solutions were fabricated by immobilizing cellulose with 8-hydroxyquinoline after grafting with glycidylmethacrylate and then treated with ethylene diamine in natural and magnetic forms to obtain R1 and R2, respectively. BET surface area measurements showed that magnetic R2 resin possesses the highest surface area (139.04 m2.g−1) when compared with cellulose (21.7 m2.g−1) or R1 (39.03 m2.g−1). Kinetic studies conducted using batch experiments showed that R2 possesses the highest uptake capacity (2.8 mmol · g−1) at pH = 2.5 with relatively fast kinetics. The adsorption process was found to fit well the pseudo-second-order model. Thermodynamic parameters indicated that the adsorption process has an endothermic spontaneous nature with increase in entropy. R2 resin may be applicable in the field of drinking water purification, especially from Fe(III) ions. GRAPHICAL ABSTRACT