Nour T. Abdel-Ghani

Typha domingensis leaf powder for decontamination of aluminium, iron, zinc and lead: Biosorption kinetics and equilibrium modeling

The present study explores the effectiveness of Typha domingensis leaf powder for simultaneous removal of aluminium, iron, zinc and lead ions from aqueous solution. Batch experiments were carried out in laboratory at room temperature and at initial ions concentrations simulating the concentrations of these cations in real wastewater samples. The sorption process was examined applying the first and second order kinetic mechanisms. The results were best described by the second order rate kinetics. The applicability of the three equilibrium isotherm models was investigated. The obtained data follow the three investigated isothermal models in the following order: Langmuir > Freundlich > Temkin, for all the studied metal ions. The infrared spectra of native and exhausted Typha leaf powder confirmed ions-biomass interactions responsible for sorption. The results showed that Typha domingensis leaf powder can easily be envisaged as a new low cost natural biosorbent for metal clean up operations in aquatic systems.

Phytoremediation of industrial wastewater potentiality by Typha domingensis

Phytoremediation is increasingly receiving attention as a cost effective technique that uses plants to remediate contaminants from wastewater, soil and sediments. In this study, the ability of Typha domingensis to uptake heavy metals as well as its potential application for phytoremediation was assessed. Pollutant elements concentrations were measured in samples of wastewater, sediments and Typha domingensis collected from industrial wastewater ponds, El-Sadat city, Egypt. This study specifically focused on the capacity of Typha domingensis to absorb and accumulate aluminum, iron, zinc and lead. Results indicated that Typha domingensis was capable of accumulating the heavy metal ions preferentially from wastewater than from sediments. The accumulation of metals in plant organs attained the highest values in roots, rhizomes and old leaves. Rhizofiltration was found to be the best mechanism to explain Typha domingensis phytoremediation capability.

Flow injection potentiometric determination of pipazethate hydrochloride

New plastic membrane electrodes for pipazethate hydrochloride based on pipazethatium phosphotungstate, pipazethatium phosphomolybdate and a mixture of the two were prepared. The electrodes were fully characterized in terms of composition, life span, pH and temperature and were then applied to the potentiometric determination of the pipazethate ion in its pure state and pharmaceutical preparations under batch and flow injection conditions. The selectivity of the electrodes towards many inorganic cations, sugars and amino acids was also tested.

Flow injection potentiometric determination of amantadine HCl.

New amantadine (Am) ion selective plastic membrane electrodes of both conventional and coated graphite types based on the ion-pair of amantadinium tetraphenylborate (Am-TPB) ion-pair are prepared. The conventional type electrode was fully characterized in terms of membrane composition, life span, pH, ionic strength and temperature. It was applied to potentiometric determination of amantadine in pure state and pharmaceutical preparation under batch and flow injection conditions. The selectivity of the electrode toward a large number of inorganic cations, sugars and amino acids was tested. The solubility product of the ion-pair and the formation constant of the precipitation reaction leading to the ion-pair formation were determined conductimetrically.

Salbutamol plastic membrane electrodes based onindividual and mixed ion-exchangers of salbutamolium phosphotungstate andphosphomolybdate

Salbutamol (Sl), also known as albuterol, selective PVC membranes based on ion associates of salbutamolium phosphotungstate (Sl-PTA), salbutamolium phosphomolybdate (Sl-PMA) or a mixture of both (Sl-PTA/PMA) were prepared. The electrodes displayed a linear response over the concentration range 6.3 × 10−6–1.0 × 10−1 mol dm−3 salbutamol sulfate (Sl2SO4). The working pH ranges of the above electrodes were 2.5–11.0, 3.0–11.0 and 2.5–10.5 and their isothermal temperature coefficients were 0.00095, 0.00105 and 0.00136 V °C−1, respectively. The electrodes showed good selectivity to salbutamolium ion with respect to many inorganic cations, sugars and amino acids. The standard additions method was used to determine Sl2SO4 in pure solutions and pharmaceutical preparations with high accuracy and precision.

Novel Ni(II) and Zn(II) complexes coordinated by 2-arylaminomethyl-1H-benzimidazole: molecular structures, spectral, DFT studies and evaluation of biological activity.

[NiL(1,2)Cl(2)(OH(2))(3)]·zH(2)O and [ZnL(1,2)(CH(3)CO(2))(2)] (L(1)=(1H-benzimidazol-2-ylmethyl)-N-phenyl amine, z=0 and L(2)=2-[(1H-Benzimidazol-2-ylmethyl)-amino]-benzoic acid methyl ester, z=1) complexes have been synthesized and characterized by a variety of physico-chemical techniques. The central Ni(II) ion is coordinated by only the pyridine-type nitrogen (N(py)) of benzimidazole ring, three water molecules and two chlorido ligands forming a distorted octahedral geometry. Five coordinated zinc complexes were obtained, where the coordination sphere of zinc ion is made up of secondary amino group (NH(sec)), N(py) and two acetate groups, one acts as a unidentate and the other as a bidentate. A theoretical DFT/UB3LYP method combined with LANL2DZ basis set shows that all the metal-ligand bonds are of the L→M type. Electronic structures have been calculated using TD-DFT method. The antibacterial activity of NiL(2) complexes decreases by the introduction of COOCH(3) group in the ortho-position of the aniline moiety.

Individual and competitive adsorption of phenol and nickel onto multiwalled carbon nanotubes.

Individual and competitive adsorption studies were carried out to investigate the removal of phenol and nickel ions by adsorption onto multiwalled carbon nanotubes (MWCNTs). The carbon nanotubes were characterized by different techniques such as X-ray diffraction, scanning electron microscopy, thermal analysis and Fourier transformation infrared spectroscopy. The different experimental conditions affecting the adsorption process were investigated. Kinetics and equilibrium models were tested for fitting the adsorption experimental data. The characterization experimental results proved that the studied adsorbent possess different surface functional groups as well as typical morphological features. The batch experiments revealed that 300 min of contact time was enough to achieve equilibrium for the adsorption of both phenol and nickel at an initial adsorbate concentration of 25 mg/l, an adsorbent dosage of 5 g/l, and a solution pH of 7. The adsorption of phenol and nickel by MWCNTs followed the pseudo-second order kinetic model and the intraparticle diffusion model was quite good in describing the adsorption mechanism. The Langmuir equilibrium model fitted well the experimental data indicating the homogeneity of the adsorbent surface sites. The maximum Langmuir adsorption capacities were found to be 32.23 and 6.09 mg/g, for phenol and Ni ions, respectively. The removal efficiency of MWCNTs for nickel ions or phenol in real wastewater samples at the optimum conditions reached up to 60% and 70%, respectively.

Spectrophotometric determination of meclozine HCl and papaverine HCl in their pharmaceutical formulations.

A simple, accurate and highly sensitive spectrophotometric method is proposed for the rapid determination of meclozine and papaverine hydrochlorides using chromotrope 2B (C2B) and chromotrope 2R (C2R). The method consists of extracting the formed ion-associates into chloroform in the case of meclozine HCl and into methylene chloride in case of papaverine HCl. The ion-associates exhibit absorption maxima at 536 and 524 nm for C2B and C2R with meclozine HCl and at 540 and 528 nm with papaverine HCl, respectively. Meclozine can be determined up to 4.0 and 2.6 mg ml(-1), using C2B and C2R, respectively, while papaverine can be determined up to 1.68 and 1.37 mg ml(-1), respectively. The effect of acidity, reagent concentration, time, solvent and stoichiometric ratio of the ion-associates were studied. The molar absorptivity and Sandell sensitivity of the reaction products were calculated. The method was applied to the determination of the drugs in their pure state or pharmaceutical preparations with mean recovery values of 99.63-100.80 and 99.75-100.08% and coefficient of variation 0.945-2.210 and 1.020-1.268 for meclozine HCl and papaverine HCl, respectively.

Construction and performance characteristics of terbutaline plastic membrane electrode in batch and FIA conditions

Abstract New plastic membrane electrode for terbutaline sulfate (Tr 2 SO 4 ) based on terbutalinium phosphotungstate (Tr-PTA) was prepared and fully characterized in terms of composition, life span, pH and temperature and then applied to the potentiometric determination of the terbutalinium ion in its pure state and pharmaceutical preparations in batch and flow injection conditions. The selectivity of the electrode towards many inorganic cations, sugars and amino acids was also tested. The results of the potentiometric determination of the drug in its pure state and pharmaceutical preparations were then compared to those obtained from the conductimetric determination of the drug. The solubility product of (Tr-PTA) was also calculated conductimetrically.

REMOVAL OF METAL IONS FROM SYNTHETIC WASTEWATER BY ADSORPTION ONTO EUCALYPTUS CAMALDULENIS TREE LEAVES

ABSTRACT Eucalyptus Camaldulenis tree leaves were used to study adsorption of several cations (Cu 2+ , Zn 2+ , Cd and Pb ) from wastewater within various experimental conditions. The dried leaves of Eucalyptus Camaldulenis were used at different adsorbent/metal ion ratios. The influence of pH, contact time, metal concentration, and adsorbent loading weight on the removal process was investigated. Batch adsorption studies were carried out at room temperature. The adsorption efficiencies were found to be pH dependent, increasing by increasing the pH in the range from2.5 to 8.5. The equilibrium time was attained after 90-120 minutes and the maximum removal percentage was achieved at an adsorbent loading weight of 1.5 g/50ml mixed ions solution. The removal order was found to be Pb (II)> Cu (II) >Cd (II)> Zn (II).This study is one of the first reports of removal of the highly toxic Cu 2+ , Zn , Cd 2+ and Pb in mixed systems based on the adsorption by natural materials. The potential of application for the treatment of solutions containing these heavy metals in multimetal solutions is indicated.Keyword: Eucalyptus camaldulenis; Lead; Copper; zinc; cadmium; Adsorption; Wastewater; Isotherms. e-mail: ghadiraly@yahoo.com