Fawwaz I. Khalili

The influence of using Jordanian natural zeolite on the adsorption, physical, and mechanical properties of geopolymers products

Geopolymers consist of an amorphous, three-dimensional structure resulting from the polymerization of aluminosilicate monomers that result from dissolution of kaolin in an alkaline solution at temperatures around 80 degrees C. One potential use of geopolymers is as Portland cement replacement. It will be of great importance to provide a geopolymer with suitable mechanical properties for the purpose of water storage and high adsorption capacity towards pollutants. The aim of this work is to investigate the effect of using Jordanian zeolitic tuff as filler on the mechanical performance and on the adsorption capacity of the geopolymers products. Jordanian zeolitic tuff is inexpensive and is known to have high adsorption capacity. The results confirmed that this natural zeolitic tuff can be used as a filler of stable geopolymers with high mechanical properties and high adsorption capacity towards methylene blue and Cu(II) ions. The XRD measurements showed that the phillipsite peaks (major mineral constituent of Jordanian zeolite) were disappeared upon geopolymerization. The zeolite-based geopolymers revealed high compressive strength compared to reference geopolymers that employ sand as filler. Adsorption experiments showed that among different geopolymers prepared, the zeolite-based geopolymers have the highest adsorption capacity towards methylene blue and copper(II) ions.

The nature of U(VI) complexation by halates and chloroacetates

Abstract The 1:1 complexation of uranyl cation with halates and haloacetates was studied in 0.10 M (NaClO 4 ) solution. The stability constants were obtained by a solvent extraction technique using 233 UO 2 2+ and the enthalpy data by calorimetric titration. The halate data were interpreted to reflect an outer-sphere nature for UO 2 ClO 3 + , an inner-sphere nature for UO 2 IO 3 + and a mixed nature for UO 2 BrO 3 + . Uranyl monoacetate was assigned an innersphere character, UO 2 ClAc + and UO 2 Cl 2 Ac + a mixed character, and UO 2 Cl 3 Ac + an outer-sphere nature.

Preparation and characterization of selected metal-humate complexes.

Soil humic acid complexes with Ca2+, Co2+, Cu2+, Th4+, and UO22+ ions were prepared using humic acid (HA) and the metal ion in aqueous solution. The solid complexes were isolated and studied by elemental analysis, solubility, infrared spectroscopy, and X-ray powder diffraction. The isolated complexes have the following empirical formulae: Ca3HA(H2O)2, CoHA (H2O), Cu2HA(H2O)3, Th4HA(H2O)2.5, and UO2HA(H2O)7. Infrared spectroscopy showed the participation of OH and COOH groups in binding to the metal ions. Also that Th4+ formed a more ionic bond with humic acid than did UO22+, which was more than Ca≈2+ Co≈s2+ Cu2+. X-ray diffraction suggested that Th4+ disturbed the humic acid structure more than UG22+, which was more than Ca2+. But, for Ca2+, Co2+, and Cu2+, Co2+, caused more disturbance than Cu2+, which was more than Ca2+, indicating that the stronger the bonding the greater the disturbance.

Chelation Properties of Some Phenolic‐Formaldehyde Polymers Toward Some Trivalent Lanthanide Ions

Abstract The chelation behavior of the phenolic‐formaldehyde polymers, poly(2,4‐dihydroxybenzoic acid‐3,5‐diylmethylene) polymer I, poly(2‐hydroxy‐benzoic acid‐3,5‐diylmethylene) polymer II, and poly(3‐hydroxybenzoic acid‐4,6‐diylmethylene) polymer III toward the trivalent lanthanide metal‐ions, La3+, Nd3+, Sm3+, Gd3+, and Tb3+ was studied by a static batch equilibration technique at 25°C as a function of contact time, pH, and counter ion. The highest metal‐ion uptake of these polymers was achieved at pH 7.0 and by using perchlorate as the counter ion. Results of the study revealed that polymer I has the highest metal‐ion uptake capacity, and that the metal‐ion uptake falls in the order: Tb3+ > Gd3+ > Sm3+ > Nd3+ > La3+.

Chelation Properties of Poly(8-Hydroxyquinoline 5,7-diylmethylene) Crosslinked with Bisphenol-A Toward Lanthanum(III), Cerium(III), Neodimium(III), Samarium(III), and Gadolinium(III) Ions

The chelation behavior of poly(8–hydroxyquinoline 5,7–diylmethylene) crosslinked with various amounts of bisphenol–A toward some trivalent lanthanide metal ions, such as La(III), Ce(III), Nd(III), Sm(III), and Gd(III), has been investigated by a static batch equilibration technique. The effects of crosslinking on the chelation characteristics of these resins were studied. The optimal capacity of metal-ion uptake was achieved by incorporating 5–10% of bisphenol–A into the polymer matrix. A scanning electron microscope was used to analyze the surface morphology of the polymers. The measured water-regain values have shown that the hydrophilicity of the crosslinked polymers increases as the degree of crosslinking is increased.

Characteristics of organosulphur compounds adsorption onto Jordanian zeolitic tuff from diesel fuel.

The removal of organosulphur compounds (ORS) from diesel fuel is an important aspect of Jordanians effort to reduce air pollution. Currently, the total sulphur content in Jordanian diesel fuel is 12,000 ppmw (1.2%, wt/wt), but Jordanian government has recently introduced new restrictions that will reduce this level gradually to internationally acceptable levels. The zeolitic tuff (ZT), from Tlul Al-Shahba region, was characterised using various analytical techniques. It was found that the Freundlich model fitted the adsorption isotherms more accurately than the Langmuir model; indicating that the ZT had a heterogeneous surface. The Langmuir adsorption capacity values for the three particle size ranges (100-200), (300-400), and (500-600) microm were 7.15, 6.32, and 5.52 mg/g and the column capacities were 4.45, 2.57, and 1.92 mg/g, respectively. The spent ZT was regenerated by washing with n-heptane with an efficiency of 81.5%. Two adsorption mechanisms were investigated. One is that the interaction of thiophene with the Brønsted site of the ZT through S atoms; the other is via C-S bond cleavage in thiophene-derived carbocations to form unsaturated fragments on the Brønsted acid sites.

Chelation properties of some mannich-type polymers toward lanthanum(III), neodymium(III), samarium(III), and gadolinium(III)

Abstract The chelation behavior of the Mannich‐type polymers, poly[8‐hydroxyquinoline‐5,7‐(piperazine‐N,N′‐diyl‐bismethylene)], polymer I, and poly[8‐hydroxyquinoline‐5,7‐(N,N′‐dimethylethylenediamine‐N,N′‐diyl‐bismethylene)], polymer II, toward the trivalent lanthanide metal ions, La(III), Nd(III), Sm(III), and Gd(III) was studied by a static batch equilibration technique as a function of contact time, pH, and counter ion. The highest metal‐ion uptake of these polymers was achieved at pH≥7.0 and by using perchlorate as the counter ion.

Extraction and spectrophotometric determination of Nd(III), Th(IV) and U(VI) in synthetic brine using Chlorophosphonazo III

A simple method has been developed to determine micromolar concentrations of Nd(III), Th(IV) and U(VI) in brine. The method involves the extractive separation of these cations from brine matrix species by using Chlorophosphonazo III as extractant with 1-butanol as solvent, and the spectrophotometric determination of the concentration of extracted species in the butanol phase. The lowest concentrations that could be determined are estimated to be 5 × 10−7 M for Nd(III) and 2 × 10−7 M for TH(IV) and U(VI).

Some lanthanide chloride complexes of pyridinaldazine and pyrrolaldazine schiff bases

Abstract Lanthanide chloride complexes with pyridinaldazine (PAA) and pyrrolaldazine (PyAA-H 2 ): [Ln(L)Cl 2 (H 2 O) n ]Cl· m H 2 O, where Ln = Ce, Nd, Sm, Yb; L = PAA, PyAA-H 2 ; n = 2, 4; m = 0, 1, 2, 3.5, have been prepared by the reaction of the corresponding lanthanide chloride with PAA or PyAA-H 2 (YbCl 3 ·6H 2 O with PyAA-H 2 gave the 2: 1 complex, [Yb 2 (PyAA)Cl 4 (H 2 O) 4 ]·2H 2 O) and characterized by spectral data, electrical conductance, magnetic susceptibility, thermal and elemental analysis.

Preparation and Characterization of Some Tetradentate Schiff Bases and their Complexes with Co(II), Ni(II) and Cu(II)

Abstract New tetradentate Schiff base ligands, H2L derived from the condensation of benzoylhydrazide with either dibenzoylmethane H2L1, benzoylacetone H2L2, or thenoyltrifluoroacetone H2L3 where synthesized and characterized by their mass spectra and elemental analyses. Complexes of the type [M(H2L)Cl2].nH2O and of the type [M(L)].nH2O (where M = Ni(II), Cu(II), and Co(II), and n = 0, 0.5, and 1 for Ni(II), Cu(II), and Co(II), respectively) were synthesized from neutral and basic solutions, respectively. These complexes were characterized on the bases of their elemental analyses, infrared, conductivity measurements, magnetic susceptibility, UV-visible and 1H-NMR spectral data. Referee I: K. Hegetschweiler Referee II: W. Klaui