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Application of central composite design for the optimization of on-line solid phase extraction of Cu-2 (+) by calix[4]arene bonded silica resin
(ELSEVIER SCIENCE BV, 2015) Memon, Fakhar N.; Ayyilidiz, H. Filiz; Kara, Huseyin; Memon, Shahabuddin; Kenar, Adnan; Leghari, Muhammad Khan; Topkafa, Mustafa
Present study deals with the optimization of on-line solid phase extraction of Cu2+ using calix[4]arene based silica resin by the assessment of central composite design of response surface methodology. The immobilized resin was characterized with FT-IR and SEM techniques. The data obtained from experimental program of central composite design was used to model the parameters that significantly affect on Cu2+ extraction. The variables chosen were metal ion concentration, pH, and temperature. Second-order quadratic model was used to approximate the effect of variables on extraction efficiency. Furthermore, suggested model was also validated with the analysis of variance. The predicted values were in good agreement with experimental results, suggesting proficient application of central composite design as an economical alternative to acquire maximum amount of information for the modeling of on-line solid phase extraction with little number of experiments. Additionally, data obtained for different concentrations was analyzed by Freundlich, Langmuir, D-R isotherms, and Scatchard plot analysis. The results suggested that Langmuir isotherm was best fit model with R-2 0.99, the energy calculated from D-R isotherm was 15.14 KJ/mol suggesting that chemical force is involved in sorption process. The method was also validated for its linearity, accuracy, and precision. (C) 2015 Elsevier B.V. All rights reserved.
Biscalixarenes: Synthesis and Investigation of the Extraction Behavior of Biscalix[4]arene Derivatives in a Two-Phase Extraction System
(MARCEL DEKKER INC, 2001) Memon, Shahabuddin; Yılmaz, Mustafa
A series of different bridged biscalix[4]arenes in which the lower rims are linked via a single site on each calixarene were synthesized and converted to their alcoholic, ketonic, and esteric derivatives. Their complexing abilities were studied by the liquid-liquid extraction of selected alkali (Li+ Na+, K+, Cs+) and transition (Cu2+, Co2+, Cd2+, Ni2+, and Hg2+) metal cations. Through extraction examination it has been deduced from the observations that the alcoholic derivatives are very poor extractants as compared to the ketonic and esteric derivatives. The ketonic derivative is selective for Hg2+, whereas the esteric derivative is not selective but a good extractant and showed higher affinity towards Na+, Cu2+, Co2+, and Hg2+. The results indicate that the ligands containing pi -system functional groups and having a proper conformation of calixarene cavity form novel binding sites for the comlexation of metal cations.
CALIXARENE BASED SORBENTS FOR THE EXTRACTION OF IONS AND NEUTRAL MOLECULES
(NOVA SCIENCE PUBLISHERS, INC, 2009) Yılmaz, Mustafa; Memon, Shahabuddin
Sorption of ions as well as organic molecules from aqueous media by calixarene based materials has been a widely developing area in material science and technology since last few decades. Mostly, it is achieved by the immobilization (physically or chemically) of modified calixarenes onto various supports such as polymers, silica, and resins. The calixarene macrocycles due to their bowl-shaped geometry are indeed used as hosts allowing organic and inorganic guests to coordinate/sorb onto their cavity. The possibility of designing versatile organic, coordination and organometallic architectures at the lower (narrow) and upper (wide) rims of the calixarenes are also very appealing for extending the cavity, or to take advantage of the proximity to promote substituent interactions. Thus, novel calixarene derivatives are continue to being synthesized and appended in polymeric materials in order to obtain regenerable resins for the recovery of various elements (metals/metalloids/non-metals) and neutral molecules. The calixarene based sorbents are generally applied in various fields such as catalyst recovery, power plant, agriculture, metals finishing, microelectronics, biotechnology processes, rare earths speciation, and potable water. Besides this, they find applications in the area of selective ion extractions, receptors, catalysis, optical devices, chemical sensor devices, the stationary phase for capillary chromatography, ion transport membranes, biomimetics, and luminescence probes etc. This survey is focused to have an overview of calixarene based sorbents for the extraction of ions and neutral molecules. The article does not, however, attempt to cover all of the different approaches to extraction processes.
Copper sorption efficiency of p-tetranitrocalix[4]arene based high performance liquid chromatographic column
(DESALINATION PUBL, 2016) Durmaz, Fatih; Memon, Fakhar N.; Memon, Shahabuddin; Memon, Ayaz A.; Memon, Naeem A.; Kara, Huseyin
Present study deals with the sorption characteristics of p-tetranitrocalix[4]arene (3) appended silica-based high-performance liquid chromatographic (HPLC) column utilized for preconcentration, determination, and purification of Cu2+ from water. The sorption characteristics of the HPLC column were investigated for Cu2+ in column agreement. The experiments were performed in five steps that were monitored using UV-visible diode-array detector. However, all the HPLC experimental results were reconfirmed by using atomic absorption spectrophotometer. The effect of concentration on the sorption efficiency of the column was evaluated for Cu2+ and data obtained was investigated using Langmuir and Freundlich sorption isotherms. The value of coefficient of determination (R-2), i.e. 0.99, suggested that the Freundlich sorption isotherm was found to be the best fit model for Cu2+. The developed method was validated for system efficiency, accuracy, and precision, while the data obtained revealed that the developed column could be applied for the sorption of Cu2+ with adequate efficiency and repeatability.
Dual Fluorescence Response of Newly Synthesized Naphthalene Appended Calix[4]arene Derivative towards Cu2+ and I-
(SPRINGER/PLENUM PUBLISHERS, 2017) Bhatti, Asif Ali; Oğuz, Mehmet; Memon, Shahabuddin; Yılmaz, Mustafa
In the present work new naphthalene appended calix[4]arene (NAC4) i.e. 5,11,17,23-tetra-tert-butyl-25,27-di((2-amido(1-naphthlene)ethyl)-26,28-dihydroxy calix[4]arene (6) was designed and successfully synthesized. NAC4 was characterized by (HNMR)-H-1 and FTIR. To explore the complexation behavior and fluorescence response of NAC4, UV-visible and fluorescence studies were carried out with series of metal ions and anions that include solvatochromic effect, ion-ligand response and interference on absorption and fluorescence spectra. Results show that the NAC4 is highly Cu2+ and I(-)selective. The ligand ion interaction follow photoinduced electron transfer (PET) mechanism. The stiochiomatric ratio of ion-ligand was calculated as 1:1 by using Job's plot method and binding constant K-a values were calculated by using Benesi-Hildebrand equation as 1x10(3) and 8x10(2) M-1 with detection limit of 1.05x10(-5) and 4.0x10(-5) M for Cu2+ and I- respectively.
An efficient calix[4]arene appended resin for the removal of arsenic
(ELSEVIER, 2011) Qureshi, Imdadullah; Qazi, Mansoor Ahmed; Bhatti, Asif Ali; Memon, Shahabuddin; Sirajuddin; Yılmaz, Mustafa
The present article represents As(III) and As(V) sorption behavior of calix[4]arene appended resins (4 and 5). It has been evaluated that resin 5 possesses greater interaction for As(III) with maximum sorption (97% at pH 1) as compared to As(V) (89% at pH 7). Similarly, it has been noticed that the behavior of resin 415 opposite to the resin 5. Its interaction with As(V) is greater (95% sorption at pH 5) than for As(III) (68% sorption at pH 1). Sorption process was also explored through FT-IR technique, which shows good interaction between sorbent and sorbate. Concerning regeneration ability, resin 4 was found to be more efficient than 5 and could be used repeatedly for the sorption of both As(III) and As(V) effectively. Best regeneration was achieved by using 0.1 M NaOH solution for desorption. The sorption process for both resins needs a very short time interval (15 to 20 min) with maximum sorption capacity (i.e.>95%). (C) 2011 Elsevier B.V. All rights reserved.
Estimation of chromium(VI) sorption efficiency of novel regenerable p-tert-butylcalix[8]areneoctamide impregnated Amberlite resin
(ELSEVIER, 2009) Qureshi, Imdadullah; Memon, Shahabuddin; Yılmaz, Mustafa
The article describes a convenient synthesis and Cr(VI) extraction efficiency of a novel p-tert-butylcalix[8]areneoctamide impregnated Amberlite (XAD-4) resin. Using p-tert-butyllcalix[8]arene macrocyclic building block, two strategies have been developed; i.e., derivatization of p-tert-butylcalix[8]arene framework with sophisticated ionophoric groups having efficiency to extract oxoanions from aqueous media and, impregnation of p-tert-butylcalix[8]arene derivative onto the polymeric support. Liquid-liquid and solid-liquid extraction experiments have been performed to evaluate the Cr(VI) extraction efficiency of both p-tert-butylcalix[8]arene derivative and the impregnated resin. From the results, it has been deduced that solid-phase extraction method is more convenient and efficient than liquid-liquid extraction process. The impregnated XAD-4 resin has been found regenerable with better extracting efficiency as compared to the simple p-tert-butylcalix[8]areneoctamide ionophore. (c) 2008 Elsevier B.V. All rights reserved.
Estimation of Chromium(VI) Sorption Efficiency of Novel Regenerable P-tert-butylcalix[8]areneoctamide Impregnated Amberlite Resin
(Crc Press-Taylor & Francis Group, 2009) Qureshi, Imdadullah; Memon, Shahabuddin; Yılmaz, Mustafa
The article describes a convenient synthesis and Cr(VI) extraction efficiency of a novel p-tertbutylcalix[8]areneoctamide impregnated Amberlite (XAD-4) resin. Using p-tert-butylcalix[8]arene macrocyclic building block, two strategies have been developed; i.e., derivatization of p-tertbutylcalix[8]arene framework with sophisticated ionophoric groups having efficiency to extract oxoanions from aqueous media and, impregnation of p-tert-butylcalix[8]arene derivative onto the polymeric support. Liquid–liquid and solid–liquid extraction experiments have been performed to evaluate the Cr(VI) extraction efficiency of both p-tert-butylcalix[8]arene derivative and the impregnated resin. From the results, it has been deduced that solid-phase extraction method is more convenient and efficient than liquid–liquid extraction process. The impregnated XAD-4 resin has been found regenerable with better extracting efficiency as compared to the simple p-tert-butylcalix[8]areneoctamide ionophore.
Evaluation of the performance of calix[8]arene derivatives as liquid phase extraction material for the removal of azo dyes
(ELSEVIER SCIENCE BV, 2008) Gungor, Omer; Yilmaz, Aydan; Memon, Shahabuddin; Yimaz, Mustafa
This pit per presents a study on the removal of azo dyes (Reactive Black 5, Trapaeolin 000, Methyl Orange and Direct Violet 51) with calix[n]arene derivatives from aqueous solution into the organic phase in order to explore the potential use of calixarenes as low-cost efficient extractants for wastewater dye removal. The carboxylic acid derivative of calix[8]arene shows highest affinity towards the azo dyes. The influence of NaCl (present in the solution) on extraction process was also Studied. The extent of the dye removal increased with the addition of NaCl. The proposed extraction mechanism involves several kinds of interactions: electrostatic repulsion between carboxylic acid groups of calix[8]arenes and sulfonate groups of azo dyes, hydrogen bonding and formation of an inclusion complex due to three dimensional cavity type calix[n]arene molecules through host-guest interactions. (C) 2008 Elsevier B.V. All rights reserved.
An Excellent Approach Towards the Designing of a Schiff-Base Type Oligocalix[4]Arene, Selective for the Toxic Metal Ions
(Taylor & Francis Inc, 2002) Memon, Shahabuddin; Yılmaz, Mustafa
A new Schiff-base type oligocalix[4]arene containing two nitrile ligating sites at narrow rim was synthesized via a simple condensation reaction through a wide rim of the calixarene moiety. The extraction ability of the oligomer with selected alkali and transition metals is compared with its monomeric analogous. It has been observed that the oligomer 6 is not selective as compared to its analogae 2 and 3, but shows a remarkable high affinity towards toxic metal cations such as Cu2+, Hg2+ and Pb2+.
An Excellent Arsenic(V) Sorption Behavior of P-tert-butylcalix[8]areneoctamide Impregnated Resin
(Elsevier France-Editions Scientifiques Medicales Elsevier, 2010) Qureshi, Imdadullah; Memon, Shahabuddin; Yılmaz, Mustafa
The present article describes the arsenic(V) extraction behavior of p-tert-butylcalix[8]-areneoctamide (3) and of a resin (4) impregnated with 3. Liquid-liquid and solid-liquid (column sorption) extraction studies were carried out to optimize various experimental parameters such as pH, extraction effeciency and column stability. Thermodynamic studies based upon Temkin and Flory-Hugins models reveal that the sorption was spontaneous and exothermic. The values of correlation coefficients (R2) show that Langmuir and Freundlich isotherm models are best fit to describe the sorption equilibrium. Application of 4 to real samples indicates a slight decrease (5-7%) in extraction efficiency of 4 because of high concentration of total dissolved salts (TDS). It is deduced that 4 is highly effective for the removal of arsenic(V) at a wide range of pH and attains a maximum value, i.e. 99% at pH 4. The impregnated resin is easy to synthesize from cheap materials. It is more efficient and easily regenerable as compared to already reported resins.
Facilitated supported liquid membrane transport of Hg2+ using calix[4] arene derivatives
(TAYLOR & FRANCIS INC, 2007) Alpoğuz, Hamza Korkmaz; Kaya, Ahmet; Memon, Shahabuddin; Yılmaz, Mustafa
The transport behavior of Hg2+ from aqueous solution through a flat-sheet supported liquid membrane has been investigated by the use of calix[ 4] arene derivatives ( 1 and 2) as carriers and Celgard 2400 and Celgard 2500 as the solid support. The effect of solvent type and anions such as chloride and nitrate ions on the transport of Hg2+ was examined. A Danesi mass transfer model was used to calculate the permeability coefficients for each parameter studied. The highest values of permeability were obtained with 2-nitrophenyloctyl-ether (NPOE) solvent and the influence was found to be in the order of NPOE. chloroform. xylene. The transport efficiency on the liquid membrane transport was dependent on the type of solvent, anion, and carrier.
Hydrogen Lon-Selective Poly(Vinyl Chloride) Membrane Electrode Based on a Calix[4]arene
(Japan Soc Analytical Chemistry, 2003) Kuruoğlu, Demet; Canel, Esin; Memon, Shahabuddin; Yılmaz, Mustafa; Kılıç, Esma
A hydrogen ion-selective poly(vinyl chloride) membrane electrode was constructed using 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetracyanomethoxycalix[4]arene as a neutral carrier. The electrode showed an apparent Nernstian response in the 2-11.5 pH range with a slope of 54.0 +/- 0.2 mV/pH at 20 +/- 1degreesC. This electrode showed a rapid response of the emf to changes in the pH, high ion selectivity with respect to lithium, sodium and potassium, and characteristics similar to those reported for the conventional pH glass membrane electrode. It can be used as a potentiometric indicator electrode in hydrofluoric acid solutions. The effects of iodide, thiocyanate, perchlorate and bromide on the characteristics of the electrode were also considered.
Kinetic study of Hg2+ transport through a liquid membrane containing calix[4]arene dinitrile oligomer as carrier
(TAYLOR & FRANCIS INC, 2005) Alpoğuz, Hamza Korkmaz; Kaya, Ahmet; Memon, Shahabuddin; Yılmaz, Mustafa
In this article, calix[4]arene dinitrile-oligomer (1) carrier was used as a carrier to transport Hg2+ ions from an aqueous solution into an aqueous receiving solution. The kinetic parameters (k(1), k(2), M-m(max), t(max) J(d)(max), J(a)(max)) were investigated with a temperature influence, solvent, and stirring rate, and analyzed in the formation of two consecutive, irreversible first order reactions. The membrane entrance rate, k(1), and the membrane exit rate, k2, constants were increased with the temperature and stirring rate, and found to be dependent on the solvent type in order to CH2Cl2 > CHCl3 > CCl4. For the maximum membrane exit flux, J(a)(max) the activation energy was found from the slope of the linear Arrhenius relationship to be 4.78 kcal/mol, which indicates that the process is controlled by species diffusion.
Kinetics of Mercury(II) Transport Through a Bulk Liquid Membrane Containing Calix[4]arene Derivatives as Carrier
(Marcel Dekker Inc, 2003) Alpoğuz, Hamza Korkmaz; Memon, Shahabuddin; Ersöz, Mustafa; Yılmaz, Mustafa
The kinetics of transport of mercury (II) ions through a bulk liquid membrane (chloroform) containing calix[4]arene nitrile derivatives as a carrier was examined at different temperatures and different stir-ring rates. The kinetics of mercury (II) transport could be analyzed in the formalism of two, consecutive, irreversible first-order reactions. The influence of temperature and stirring-rate on kinetic parameters also have been investigated. The membrane entrance rate, k(1), and the membrane exit rate, k(2), increased with increasing temperature and increasing stirring rate. For maximum membrane exit fluxes, J(a)(max), the activation energies were found as 1.923 +/- 0.15 and 2.112 +/- 0.2 kj/mol, for ligand carrier 1 and 2, respectively. The values for the found activation energy indicate that the process is controlled by species diffusion.
Novel Calix[4]arene-based Amberlite XAD-4 Modified Resin for As(III) Removal from Water
(WILEY, 2013) Qureshi, Imdadullah; Memon, Shahabuddin; Yılmaz, Mustafa
The present article describes As(III) sorption behavior of novel calix[4]arene appended TS-4 resin. The sorption ability of TS-4 resin has been evaluated at wide range of pH, i.e., pH 214. The maximum As(III) sorption efficiency (95%) was achieved at pH 2, which shows that the TS-4 resin possesses greater affinity for As(III) at this pH. Column sorption mechanism was evaluated through various operating parameters, i.e., change in concentration, flow rate, bed heights, and pH. The experimental data were also tested against bed depth service time model and from the results; it has been observed that the data is in close agreement with the theoretically calculated values. Thus, from the data it has been revealed that TS-4 resin has maximum column efficiency of 0.13mmolg1. Application of TS-4 to real samples indicates a slight decrease (23%) in extraction efficiency of TS-4 because of high concentration of total dissolved salts. Thermal behavior was tested by differential scanning calorimetry and it has been observed that TS-4 resin is stable up to 160 degrees C. TS-4 resin was found to be regenerable and best regeneration was achieved by using 4% solution of NaOH. It can be deduced from the study that the resin will find its applicability in small as well as industrial scale water purification plants.
Polymer Supported Calix[4] Arene Derivatives for the Extraction of Metals and Dichromate Anions
(Kluwer Academic/Plenum Publ, 2003) Memon, Shahabuddin ; Akceylan, Ezgi; Sap, Begüm; Tabakçı, Mustafa; Roundhill, D. Max; Yılmaz, Mustafa
Three newly synthesized polymer supported calix[ 4] arene ionophores (7-9) were synthesized, and their ion binding properties toward selected alkali (Li+, Na+, K+, Cs+) and transition metal (Hg2+, Ni2+, Cu2+, Co2+, Cd2+, and Pb2+) cations were investigated. It has been observed that these ionophores are not selective toward a particular metal cation but show better ion binding property as compared to monomeric calixarene derivatives (2 and 6). Ionophore 6 and its supported polymer were also employed in dichromate anion extraction experiments. The polymeric ionophore (9) was found an effective extractant for dichromate anion even at pH 7.
Preconcentration and Determination of Toxic Metals by A New Calix[4]arene Bonded HPLC Column
(SPRINGER HEIDELBERG, 2013) Durmaz, Fatih; Memon, Fakhar N.; Memon, Naeem A.; Memon, Sibghatullah; Memon, Shahabuddin; Kara, Huseyin
The present study deals with the preconcentration and determination of toxic metal ions using p-tetranitrocalix[4]arene (3) appended silica-based new HPLC column. The synthesized material was characterized using Fourier transform infrared and scanning electron microscopy techniques. The sorption characteristics of the HPLC column were investigated for three toxic metals (Cd2+, Hg2+ and Pb2+) in column agreement. The experiments were performed in five steps that were monitored using a UV-visible diode-array detector. However, all the HPLC experimental results were reconfirmed by using atomic absorption spectrophotometer. The effect of concentration on the sorption efficiency of the column was evaluated for all the three metals and the data obtained were investigated using Langmuir, Freundlich and Dubinin-Redushkevich (D-R) sorption isotherms. The value of coefficient of determination (R (2)), i.e. 0.99, suggested that the Freundlich sorption isotherm was found to be the best-fit model for all the three toxic metal ions, whereas, mean free energy was calculated from the D-R isotherm as 5.3, 5.7, and 5.8 kJ/mol for Pb2+, Cd2+, and Hg2+, respectively; suggesting that physical electrostatic force is involved in the sorption process. The developed method was validated for system efficiency, accuracy, and precision.
Removal of Direct Azo Dyes and Aromatic Amines From Aqueous Solutions Using Two Beta-Cyclodextrin-Based Polymers
(Elsevier, 2010) Yılmaz, Elif; Memon, Shahabuddin; Yılmaz, Mustafa
Two beta-cyclodextrin (beta-CD)-based polymers were synthesized using 4,4'-methylene-bis-phenyldiisocyanate (MDI) or hexamethylenediisocyanate (HMDI) as a cross linking agent in dimethylformamide and used as sorbents for the removal of azo dyes (Evans Blue and Chicago Sky Blue), as well as aromatic amines (benzidine. p-chloroaniline and alpha-naphthalamine) from aqueous solutions. The sorption experiments were carried out by using batch-wise procedure involving the determination of pH effect, sorbate concentration and contact time. Moreover, from the equation isotherms such as Langmuir and Freundlich were successfully applied to model the experimental data. From the results polymer 2 was found to be a better sorbent for both azo dyes and the aromatic amines as compared to polymer I as proved by Langmuir isotherm model. The proposed sorption mechanism involved several kinds of interactions: physical adsorption, hydrogen bonding and formation of an inclusion complex due to the beta-CD molecules through host-guest interactions.
Removal of toxic metals from canola oil by newly synthesized calixarene-based resin
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2018) Kamboh, Muhammad Afzal; Memon, Shahabuddin; Zardari, Liaquat Ali; Nodeh, Hamid Rashidi; Sherazi, Syed Tufail Hussain; Yılmaz, Mustafa
This study describes the synthesis, characterization, and application of a new p- sulfonatocalix[4]arene-based silica resin (calix-resin 5) for the extraction of selected metals, namely Pb, Cd, Co, Ni, Cu and Fe, from canola oil. Synthesis, morphology, purity, and elemental composition of calix-resin 5 were analyzed by FT-IR spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy. The metal extraction efficiency of calix-resin 5 was evaluated through the batch-wise method with a flame and graphite furnace atomic absorption spectrometer following the wet acid digestion procedure. The results obtained showed that the newly fabricated adsorbent material calix-resin 5 is an efficient adsorbent and exhibits great potential as an alternative adsorbent for the extraction of selected Pb, Cd, Co, Ni, Cu, and Fe in canola oil metal extraction as compared to conventional clay or pure silica.

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