Synthesis, characterization and structure effects on selectivity properties of silica gel covalently bonded diethylenetriamine mono- and bis-salicyaldehyde and naphthaldehyde Schiff,s bases towards some heavy metal ions

Soliman, Ezzat M.; Mahmoud, Mohamed E.; Ahmed, Salwa A.

doi:10.1016/s0039-9140(00)00648-2

Cited by 113 publications

(62 citation statements)

References 23 publications

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“…Sorption capacities of similar types of silica base immobilized metal chelate Schiff bases were also evaluated extensively by some other authors for metal ions like Fe 3+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ and Pb 2+ . 24 The reactivity of metal ion sorption was discussed in the light of bulkiness, orientation of immobilized chelate, and participation of azomethene nitrogen and phenolic hydroxyl group oxygen atoms. In the present case, the preconcentration factor for the elution of Zn 2+ using a column technique was found to be 66.2 with a breakthrough volume of 15 cm 3 .…”

Section: Discussionmentioning

confidence: 99%

Extraction of Metal Ions Using Chemically Modified Silica Gel Covalently Bonded with 4,4’-Diaminodiphenylether and 4,4’-Diaminodiphenylsulfone-salicylaldehyde Schiff Bases

et al. 2006

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Silica gel is an amorphous inorganic polymer containing an internal siloxane group (Si-O-Si) with silanol groups (Si-OH) distributed on the surface.1,2 It is commonly used as a rigid matrix for ligand immobilization. 3 The chemical modification of silica gel surfaces with donor atoms such as N, S, O and P is primarily aimed at improving the adsorption and exchange properties of the silica gel along with incorporation of the particular selective characteristics into the modified silica gel phases towards certain metal ions. 4 The immobilization of chelating materials containing donor atoms on the silica gel surface can occur via chemical bond formation between organic modifiers like amino or chloro modified silica gel phases or through simple physical adsorption processes.5 Such a process often incorporates selectivity in synthesized materials. 6,7 Several new chemically modified silica gels were synthesized, and applied as normal or selective solid phase extractor for many toxic and other metal ions. They were found to be superior to the conventional ion exchange resins in their ability to extract and selectively preconcentrate the heavy metal ions from solutions containing high concentrations of alkali and alkaline earth metal ions. [8][9][10] Advantages of the modified solid phase extractors compared with the classical liquid extractor's were reported in many references. 11,12Schiff bases, having multidentate coordination sites, are known to form complexes with transition metal ions readily. 13,14The Schiff bases derived from salicylaldehyde (Salens) as polydentate ligands are known to form stable complexes with transition metal ions. 15,16 The present work describes the syntheses of two new chemically modified silica gel covalently bonded with 4,4′-diaminodiphenylether and 4,4′-diaminodiphenylsulfonesalicylaldehyde Schiff bases.The synthesized chelating materials were used for the preconcentration and separation of Cr 3+ , Zn 2+ , and Mn 2+ from dilute aqueous solutions. They were compared to determine their metal binding, extraction and selective abilities using batch techniques. The more reactive chelating material, Si-DDE-o-HB, was utilized in a column technique for the preconcentration of Zn 2+ and Cr 3+ . Elution of the sorbed cations in column experimental studies provided an example of using the chelating material in continuous cycle operation and recovery of the metal ions. The analytical precision and accuracy of the result were tested with satisfactory results, and the method was found to be rapid, precise, simple and convenient to use. Experimental ApparatusThe specific surface areas of the dry silica and loaded silica were determined by BET method on NOVA 1000, high speed gas sorption analyzer, Quantachrome Corporation, USA. A Shimadzu atomic absorption spectrophotometer (Model AA-680) equipped with a single element hollow cathode lamp and an air-acetylene burner was used for the estimation of metal ions. The instrument parameters were those recommended by the manufacturer. The wave lengths (nm) s...

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Section: Discussionmentioning

confidence: 99%

Extraction of Metal Ions Using Chemically Modified Silica Gel Covalently Bonded with 4,4’-Diaminodiphenylether and 4,4’-Diaminodiphenylsulfone-salicylaldehyde Schiff Bases

et al. 2006

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“…43 To investigate the temperature effects, 22 three weights of 50 mg each of the phase were kept for 1 h at 50, 60, 70, 75 and 100 C in an electric oven, and then left to cool. To show the extent of decomposition or hydrolysis of the immobilized chelate on a silica surface, 25 mg of each medium and thermally treated phases along with an untreated one taken as the standard, were used to evaluate the Ca(II) ion sorption capacity under the same conditions as previously described for batch experiments and the pH of the highest uptake, and then comparing the Ca(II) uptake values obtained with that of the standard untreated one.…”

Section: Stability Of the Phasesmentioning

confidence: 99%

“…On the other hand, the surface concentration of both 8-aminoquinoline and 2-aminopyridine bound to the CMSG surface were found to be 0.390 and 0.553 mmol g -1 , respectively based on a probe method. 43 The values of the surface coverage are in harmony with the number of aromatic rings. Thus, the concentrations of 2-aminopyridine (one aromatic ring) on silica surfaces were higher than that of 8-aminoquinoline, regardless of the stability of the metal complex formed, as discussed later.…”

Section: Infrared Spectra and Surface Coverage Of The New Solid-phasementioning

confidence: 99%

“…The selectivity of solid-phase extractors mainly depends on the structure of the immobilized organic compound, the nature of the incorporated donor atoms, the positioning of the functional groups along the surface of the solid support and the steric requirements of the complex formed after uptake of the desired metal ion. 43 Consequently, a large number of silica gel-supported organic moieties have been synthesized and applied regarding in different research aspects. However, a survey of the literature reveals that little work has so far been reported regarding the simultaneous determination of calcium and magnesium using silica-gel phases.…”

Section: Introductionmentioning

confidence: 99%

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Solid-Phase Extractors Based on 8-Aminoquinoline and 2-Aminopyridine Covalently Bonded to Silica Gel for the Selective Separation and Determination of Calcium in Natural Water and Pharmaceutical Samples

Soliman¹,

Ahmed

2010

ANAL. SCI.

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“…2-Amino-1-cyclopentene-1-dithiocarboxylic acid, salicylaldehyde and naphthaldehyde Schiff bases based on silica gel, 28 1-(2-thiazolylazo)-2-naphthol, 29 quinalizarine 30 and 8-hydroxyquinoline immobilized on fluorinated metal alkoxide glass 20 are selected examples. Among various supports, silica has an advantage over organic polymers owing to its good mechanical and thermal stability, and it is less susceptible to swelling and shrinking as well as microbial and radiation decay.…”

Section: Introductionmentioning

confidence: 99%

Controlled-pore Silica Glass Modified with N-Propylsalicylaldimine for the Separation and Preconcentration of Trace Al(III), Ag(I) and Hg(II) in Water Samples

Mostafa

Hassanien²,

Abou‐El‐Sherbini

et al. 2003

ANAL. SCI.

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Controlled-pore silica glass modified with N-propylsalicylaldimine (SCPSG) has been investigated as a surface-active matrix for the separation of some metal ions. The porous silica glass base was confirmed to have better stability towards hydrolysis in aqueous solution buffered at pH = 9 in comparison to silica gel, which showed twice the surface area of controlled-pore silica glass. The different analytical parameters affecting the batch mode separation and preconcentration of trace Al(III), Ag(I) and Hg(II) in environmental samples using SCPSG, prior to their determination using inductively coupled plasma mass spectrometry (ICP-MS), were studied. The optimum conditions are pH 9.0 ± 0.1, time of stirring 30 min and the eluent concentration 0.5 mol dm -3 HNO3. The ion-exchange capacity of SCPSG with respect to Al(III), Ag(I) and Hg(II) was 0.27, 0.18 and 0.23 mmol g -1 , respectively. The recovery values for the metal ions were 96.8 ± 0.86, 98.1 ± 0.60 and 96.2 ± 1.06%, and the analytical detection limits were 26.1, 1.49 and 0.44 pg cm -3 , respectively, for a preconcentration factor of 100. The method has been applied to the determination of the investigated metal ions in natural water samples as well as certified and reported samples and the results were found to be accurate.

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Synthesis, characterization and structure effects on selectivity properties of silica gel covalently bonded diethylenetriamine mono- and bis-salicyaldehyde and naphthaldehyde Schiff,s bases towards some heavy metal ions

Cited by 113 publications

References 23 publications

Extraction of Metal Ions Using Chemically Modified Silica Gel Covalently Bonded with 4,4’-Diaminodiphenylether and 4,4’-Diaminodiphenylsulfone-salicylaldehyde Schiff Bases

Extraction of Metal Ions Using Chemically Modified Silica Gel Covalently Bonded with 4,4’-Diaminodiphenylether and 4,4’-Diaminodiphenylsulfone-salicylaldehyde Schiff Bases

Solid-Phase Extractors Based on 8-Aminoquinoline and 2-Aminopyridine Covalently Bonded to Silica Gel for the Selective Separation and Determination of Calcium in Natural Water and Pharmaceutical Samples

Controlled-pore Silica Glass Modified with N-Propylsalicylaldimine for the Separation and Preconcentration of Trace Al(III), Ag(I) and Hg(II) in Water Samples

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