A. M. Siliman
Bio: A. M. Siliman is an academic researcher. The author has contributed to research in topic(s): Fission products & Nitrate. The author has an hindex of 2, co-authored 2 publication(s) receiving 8 citation(s).
Abstract: Separation of palladium by strongly basic anion exchangers IRA-110 and IRA-900 from intermediate radioactive liquid waste in chloroacetic acid/nitrate medium containing thirteen elements have been achieved. Different conditions have been studied, the effect of NaNO3 as salt content, chloroacetic acid and hydrogen ion concentration have been investigated. Selective recovery of palladium from the [ILLW] solution was achieved using the column technique. The selectivity increased by using chloroacetic acid/nitrate than in nitrate medium. The elution of palladium was carried out via reduction with formic acid where the rate of the reduction process was increased by decreasing the formic acid concentration till 50% followed by dissolving the separated palladium by nitric acid.
Abstract: Zirconium phosphate hase been prepared by solid-solid reaction. The characterization of this inorganic ion exchanger was done with respect to capacity, pH titration, dissolution, etc. The preconcentration and separation of fission products, Sr(II), Co(II), Eu(III), Gd(III), Hg(II) and Am(III) has been achieved from different acidic media, HCl, HNO3, H2SO4, HClO4. The speciation of these cations in different media has been investigated. From the results obtained, it is obvious that these cations can be preconcentrated in low acidic medium, whilst at high acidity in the range 1-2 M, they be can separated from each other.
Abstract: A nano material was obtained by dopping ZP in mesoporous nanocarbon which prepared by physical activation carbon via thermal effect .A series of ZP materials dopped in activated carbon obtained from DP by physical activation. The dopped ZP-C materials were heat-treated at various temperatures, 100–800 0 C. TGA & DTG thermal analysis showed that incorporation of the doping agent within the carbon DP layered materials which enhanced the heat-resistivity of the nanohybrid materials in the thermal decomposition pathway. Porous carbon materials can be obtained from the heat-treatment of the nanohybrids at 700 and 900 0 C. Calcination of the dopped material was achieved at 900 0 C under nitrogen atmosphere which produces mesoporous and high pore volume carbon materials. According to the kinetics of Freeman–Carroll and Coats–Redfern the calculated order of reaction of ZP in DP is 2. The calculated activation energy of both matrices are 402 and 350 kJ mol –1 . Key Words: Activated carbon; solid waste DP; physical activation; ZP; and nanotechnology
01 Jan 2013
Abstract: A novel ion selective IRA-410 membrane disc sensor for Pd (II) ions has been prepared and studied. This electrode has a wide linear dynamic range from 10-1 to 2.5×10-6 mol-1 with a Nernstian slope of 16.5 ± 0.2 mV decade-1 and low detection limit of 1.6×10-6 mol l-1. It has a fast response time (<1 s) and good selectivity with respect to different metal ions. IRA-410 based electrode was suitable for aqueous solutions of pH range from (1.0- 9.0). It can be used for about 10 months with complex with Pd (II) was calculated by using segmented sandwich membrane method. The formation constant of ionophore of IRA-410 and its Pd (II)-Complex is examined using Fourier-transform infrared analysis and elemental analysis techniques. The proposed electrode has been used successfully as an indicator electrode in potentiometric determination in aqueous nitrate and /or chloride media.
Abstract: Calcium phosphate with hydroxyapatite structure was synthesized and its ability to adsorb Cr(VI) from aqueous solution is presented. XRD, BET, IR, TGA, SEM and EDS techniques were used to characterize the obtained material. A pure phase was obtained through a simple synthesis process. The specific surface area of the synthesized powder was found to be 64.5 m 2 g -1 . The X-ray diffraction pattern shows that the calcium phosphate formed was nanocrystalline with an average grain size of approximately 75 nm. A fast adsorption was observed and in less than 24 h it was found that 2.41 x 10 -4 meq g -1 of Cr(VI) ions were adsorbed on calcium phosphate. Desorption experiments showed that Cr(VI) adsorption decreased to 2.23 x 10 -4 meq g -1 of calcium phosphate. This behavior is a consequence of partial dehydration of the synthesized material. Calcium phosphate can be effectively used for removing Cr(VI) from aqueous solutions in treatment processes of metal wastes.
TL;DR: This review describes the basic types of available sorbents, preconcentration procedures and preparations of the sorbent to the subsequent determination of noble metals and specific features of instrumental techniques and examples of ETAAS, FAAS, I CP-AES, ICP-MS determinations after the sorption preconcentrations are considered.
Abstract: Nowadays much attention is being paid to the determination of trace amounts of noble metals in geological, industrial, biological and environmental samples. The most promising techniques, such as inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ETAAS) are characterized by high sensitivity. However, the accurate determination of trace noble metals has been limited by numerous interferences generated from the presence of matrix elements. To decrease, or eliminate, these interferences, the sorption preconcentration of noble metals is often used prior to their instrumental detection. A great number of hyphenated methods of noble metal determination using sorption preconcentration have been developed. This review describes the basic types of available sorbents, preconcentration procedures and preparations of the sorbent to the subsequent determination of noble metals. The specific features of instrumental techniques and examples of ETAAS, FAAS, ICP-AES, ICP-MS determinations after the sorption preconcentration of noble metals are considered. The references cited here were selected mostly from the period 1996 - 2006.
Abstract: Electrochemical behavior of palladium (II) chloride in 1-butyl-3-methylimidazolium chloride has been investigated by various electrochemical transient techniques using glassy carbon working electrode at different temperatures (343–373 K). Cyclic voltammogram consisted of a prominent reduction wave at −0.61 V (vs. Pd) due to the reduction of Pd(II) to Pd, and two oxidation waves at −0.26 and 0.31 V. A nucleation loop is observed at −0.53 V. The diffusion coefficient of palladium (II) in bmimCl (∼10 −7 cm 2 /s) was determined and the energy of activation (63 kJ/mol) was deduced from the cyclic voltammograms at various temperatures. Nucleation and growth of palladium on glassy carbon working electrode has been investigated by chronoamperometry and chronopotentiometry. The growth and decay of chronocurrents measured for palladium deposition has been found to follow the instantaneous nucleation model with three-dimensional growth of nuclei. The surface morphology of the deposit obtained at various applied potentials revealed the formation of dendrites immediately after nucleation and spread in all the directions with time.
Author's H-index: 2