Yazar "Uslu, Hasan" seçeneğine göre listele
Listeleniyor 1 - 20 / 87
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Adsorption equilibria of formic acid by weakly basic adsorbent Amberlite IRA-67: Equilibrium, kinetics, thermodynamic(Elsevier Science Sa, 2009) Uslu, HasanFormic acid is an important chemical and biochemical compound used in various industries. It is important to separate this acid from wastewater streams. In this study, adsorption of formic acid was studied from aqueous solution by using weakly basic adsorbent (Amberlite IRA-67) at three different temperatures (298K, 318 K, and 328 K). Adsorption of formic acid was investigated in terms of equilibrium, kinetics and thermodynamic conditions. Optimal amount of IRA-67 was determined as 1.00 g. The most used isotherms, Freundlich and Langmuir, were applied to experimental data. Langmuir isotherm gave good results with R-2 value over 0.99 at different temperatures. Pseudo-second-order model was fitted for this adsorption system. Thermodynamic parameters, Delta H-ads degrees, Delta S-ads degrees and Delta G(ads)degrees, were calculated. (C) 2009 Elsevier B.V. All rights reserved.Öğe Adsorption Equilibria of L-(+)-Tartaric Acid onto Alumina(Amer Chemical Soc, 2009) Uslu, Hasan; Inci, IsmailThe adsorption equilibria of L-(+)-tartaric acid onto alumina from wastewaters of wineries were studied, and it has been found that the equilibrium adsorption fits the Langmuir and Freundlich isotherms. Adsorption experiments were carried out at three different temperatures (298, 310, and 325) K. The adsorption Of L-(+)tartaric acid is dependent on the acid concentration and the amount of alumina. The maximum percentage removal of L-(+)-tartaric acid was 22 % by alumina at 298 K. The Langmuir and Freundlich constants have been found to be 0.023 g.g(-1) and 0.014 (g.g(-1))/(L.g(-1))(-1/n), respectively, at 298 K. The thermodynamic parameters Delta H-ads(0) and Delta S-ads(0) for the adsorption of tartaric acid on alumina have been calculated to be -5.62 kJ.mol(-1) and 50.65 J.mol(-1).K-1, respectively.Öğe Adsorption Equilibrium Data for Acetic Acid and Glycolic Acid onto Amberlite IRA-67(Amer Chemical Soc, 2010) Uslu, Hasan; Inci, Ismail; Bayazit, Sahika SenaThe removal of acetic acid and glycolic acid from aqueous Solution by the weakly basic adsorbent Amberlite IRA-67 has been Studied at three different temperatures. Amberlite IRA-67 removed both acids very well from aqueous Solution. The maximum adsorption efficiency has been found to be 86.29% and 61.36% for glycolic acid and acetic acid, respectively. Langmuir and Freundlich adsorption isotherms have been applied to the experimental data. The Langmuir isotherm fitted the experimental data better than the Freundlich isotherm for both acids. Thermodynamic parameters Delta G, Delta H, and Delta S were calculated.Öğe Adsorption of Glutaric Acid and Glyoxylic Acid onto Weakly Basic Ion-Exchange Resin: Equilibrium and Kinetics(Amer Chemical Soc, 2010) Bayazit, Sahika Sena; Inci, Ismail; Uslu, HasanAdsorption equilibria Of glutaric acid and glyoxylic acid on a weakly basic ion-exchanger which has a tertiary amine functional group were investigated experimentally and theoretically in this study. Amberlite IRA-67 was used as the ion-exchange resin. The time to reach an equilibrium state, effects of amount of adsorbent, temperature, and initial acid concentrations on adsorption efficiency and distribution coefficient of acid adsorption were investigated, experimentally. The Langmuir, Freundlich, and Temkin adsorption isotherms were calculated. The equilibrium isotherms were significantly dependent on initial acid concentration. The Langmuir isotherm was found to best represent the data for both acids. The adsorption of both acids followed pseudosecond-order kinetics. Diffusion is not the only rate-controlling step.Öğe Adsorption of Lactic Acid from Model Fermentation Broth onto Activated Carbon and Amber lite IRA-67(Amer Chemical Soc, 2011) Bayazit, Sahika Sena; Inci, Ismail; Uslu, HasanThe aim of this study was to compare the adsorption efficiency of lactic acid onto activated carbon and Amberlite IRA-67, and to define the adsorption isotherms. Activated carbon is a well-known industrial adsorbent and was used in this study; Amberlite IRA-67 is a weakly basic polyacrylic resin with a tertiary amine functional group. Adsorption efficiencies of activated carbon and Amberlite IRA-67 were compared with respect to their percentage of removal acid. The result of this comparison is that Amberlite IRA-67 is more efficient than activated carbon. Each of these adsorbents is in compliance with both the Freundlich and Langmuir isotherms.Öğe Adsorption of Picric Acid from Aqueous Solution by the Weakly Basic Adsorbent Amber lite IRA-67(Amer Chemical Soc, 2010) Uslu, Hasan; Demir, GoekselThe presence of nitrophenols in wastewater is of great environmental concern. Therefore, it is important to separate picric acid from wastewater streams. In this study, adsorption of picric acid was studied from aqueous solutions by using a weakly basic adsorbent (Amber lite IRA-67) at three different temperatures (298 K, 308 K, and 318 K). Adsorption of picric acid was investigated in terms of equilibrium, kinetics, and thermodynamic conditions. In the equilibrium studies, 1.00 g of Amber lite IRA-67 was determined as the optimal amount. The most used isotherms, Freundlich and Langmuir, were applied to the experimental data. The Langmuir isotherm gave good results with R squared values over 0.99 at different temperatures. In the kinetic studies, pseudofirst- and pseudosecond-order models and the Elovich equation were applied to the kinetic experiments. The pseudosecond-order model was fitted to this adsorption system with an R squared value of 0.996. In the thermodynamic studies, Delta H-ads(0) = -21.204 kJ.mol(-1), Delta S-ads(0) = -200.043 J.mol(-1).K-1, and Delta G(ads)(0) for different temperatures were calculated.Öğe Adsorptive separation of adipic acid from aqueous solutions by perlite or its composites by manganese or copper(Techno-Press, 2014) Uslu, Hasan; Demir, Goksel; Bayat, Cuma; Wasewar, Kailas L.; Bamufleh, Hisham S.Adipic acid (hexane-1,6-dioic acid) is one of the most used chemical in industrial applications. This must be separated from any environmental contaminant. In this study, adipic acid separation from wastewater by adsorption method onto Perlite or Perlite + Mn or Perlite + Cu composites was investigated. Adsorption of Adipic acid was investigated in terms of equilibrium, and thermodynamic conditions. For thermodynamic investigations the experiments carried out at three different temperatures (298 K, 318 K, 328 K). In the equilibrium studies, 2 g of perlite and its composites were determined as the optimal adsorbent amount. Freundlich and Langmuir isotherms were applied to the experimental data. Freundlich isotherms for all temperatures used in this work gave some deviations with R square values under 0.98 where as Langmuir isotherm gave good results with R square values upper 0.99 at different temperatures. As a result of thermodynamic studies, adsorption enthalpy (Delta H), adsorption entropy (Delta S), and adsorption free energy (Delta G) have been calculated for each adsorbents.Öğe Adsorptive Separation of Cu2+ from an Aqueous Solution Using Trioctylamine Supported Montmorillonite(Amer Chemical Soc, 2015) Datta, Dipaloy; Uslu, Hasan; Kumar, SushilMontmorillonite (Mt) was used to remove copper (Cu2+) ion from wastewater stream generated from industrial effluents. This clay was modified (Mt-TOA) by using an amine-based solvent, trioctylamine (TOA). Equilibrium and kinetic experiments were carried out to determine the effect of adsorbent amount (w, 0.05 g to 0.3 g for Mt, 0.001 to 0.006 g for MtTOA), initial Cu2+ ion concentration (C-0, 8 mg.L-1 to 16 mg.L-1), pH (2 to 10), and contact time (t, 10 to 90 min) on the capacity of both adsorbents. With an increase in the adsorbent amount, the uptake capacity of Mt and Mt-TOA for Cu2+ ion was found to decrease but with an enhancement in the removal efficiency. The optimum amount of Mt and Mt-TOA was found to be 0.1 and 0.001 g, respectively. A better adsorption of Cu2+ ion was observed at low pH value of aqueous solution, and was found to decrease with an increase in the value of pH. In the kinetic experiments, the amount removal of Cu2+ ion reached to a constant value of 75.62 % with Mt (0.1 g) and 80.12 % with Mt-TOA (0.001 g) after 70 min. Equilibrium and kinetic data were analyzed by using eight different isotherm (Langmuir, Freundlich, Elovich, Temkin, Dubinin-Radushkevich, Redlich-Peterson, Toth, and Sips) and two different kinetic (pseudo-first-order and pseudo-second-order) models, respectively.Öğe Comparative Equilibrium Studies for Citric Acid by Amberlite LA-2 or Tridodecylamine (TDA)(Amer Chemical Soc, 2009) Bayazit, Sahika Sena; Uslu, Hasan; Inci, IsmailCarboxylic acids like citric acid are produced by fermentation. They have been used in many industrial fields as intermediate and starting materials, and their importance is still growing. It is important to separate them from the fermentation broth. In this sense, comparison of different types of solvents and amines for extraction of carboxylic acids from the fermentation broth and the most effective amine-solvent composition is sought. Studies have been performed on the extraction of citric acid from fermentation broth by tridodecylamine (TDA) (a long chain tertiary amine), and Amberlite LA-2 (a secondary amine mixture). These extractants were dissolved in different solvents having different chemical structures. The extractions were carried out at 298 K. Comparison of the results were made using the distribution coefficient, loading factor, separation factor, and the percentage of extraction yield. The most effective solvent was determined as 1-octanol for both TDA and Amberlite LA-2 with a distribution value of 29.63 and 103.80, respectively. The maximum value of the extraction efficiency was found to be 99.05 % with Amberlite LA-2 in 1-octanol.Öğe A comparative study for adsorption of carbolic acid by synthetic resins(Techno-Press, 2015) Uslu, Hasan; Bamufleh, Hisham S.Carbolic Acid which is called phenol is one of the important starting and/or intermediate materials in various industrial processes. However, its excessive release into environment poses a threat to living organisms, as it is a highly carcinogens and hazardous pollutant even at the very low concentration. Thus removal of phenol from polluted environments is very crucial for sustainable remediation process. We developed a low cost adsorption method for separating phenol from a model aqueous solution. The phenol adsorption was studied using two adsorbents i.e., Amber lite XAD-16 and Amber lite XAD-7 HP with a constant amount of resin 0.1 g at varying aqueous phenol concentrations (50-200 mg L-1) at room temperature. We compared the efficacy of two phenol adsorbents for removing higher phenol concentrations from the media. We investigated equilibrium and kinetics studies of phenol adsorption employing Freundlich, Temkin and Langmuir isotherms. Amberlite XAD-16 performed better than Amberlite XAD-7 HP in terms of phenol removal efficiency that amounted to 95.52%. Pseudo second order model was highly fitted for both of the adsorption systems. The coefficient of determination (R-2) with Langmuir isotherm was found to be 0.98 for Amberlite XAD-7 HP. However, Freundlich isotherm showed R-2 value of 0.95 for Amberlite XAD-16, indicating that both isotherms could be described for the isotherms on XAD-7 HP and Amberlite XAD-16, respectively.Öğe Comparison of Solid-Liquid Equilibrium Data for the Adsorption of Propionic Acid and Tartaric Acid from Aqueous Solution onto Amberlite IRA-67(Amer Chemical Soc, 2009) Uslu, Hasan; Inci, Ismail; Bayazit, Sahika Sena; Demir, GoekselInvestigation of adsorption parameters such as effect of initial acid concentration, effect of amount of adsorbent, effect of temperature,;, effect of contact time, fitting data to isotherms, and kinetic models for propionic acid and tartaric acid by using Amberlite IRA-67 adsorbent was studied. The maximum adsorption efficiencies were found to be 97.18% and 84.46% for tartaric acid and propionic acid, respectively. The best fitted isotherm was determined to be Langmuir for tartaric acid. The Langmuir isotherm was better fitted than the Frundlich isotherm for both acids. Elovich model equation was applied for data of each acids. The kinetics of the adsorption for both acids was determined as pseudo-second-order model.Öğe Comparison of the Efficiencies of Amine Extractants on Lactic Acid with Different Organic Solvents(Amer Chemical Soc, 2011) Bayazit, Sahika Sena; Uslu, Hasan; Inci, IsmailThe aim of this study is to compare different types of solvents and amines for extraction of carboxylic acids from fermentation broth and to find the most effective amine solvent composition for the extraction. Studies have been made of the extraction of L-(+)-lactic acid and citric acids from fermentation broth by tridodecylamine (TDA), a long-chain tertiary amine, and Amber lite LA-2, a secondary amine mixture. These extractants dissolved in different solvents which have different chemical structures. The extraction of acids was carried out at 298 K. Comparison of the results was made using the distribution coefficients (K-d), loading factor (Z), and the percentage of extraction yield. 1-Octanol was found to be the most effective solvent with a maximum distribution value of 4.25 and 37.93 for TDA and Amberlite LA-2, respectively.Öğe A comperative study for adsorption of methylene blue from aqueous solutions by two kinds of amberlite resin materials(Desalination Publ, 2012) Kerkez, Ozge; Bayazit, Sahika Sena; Uslu, HasanAn organic dye, methylene blue (MB), was separated from a model aqueous solution by using adsorption method with low cost resin adsorbents. The adsorption of MB was studied with Amberlite XAD-16 and Amberlite XAD-7 HP. The aim of the study is to achieve a high removal value of the dye and comparing these two adsorbents for MB adsorption. Adsorption of MB was investigated in terms of equilibrium and kinetics conditions. Adsorption isotherms were determined and correlated with equations such as Freundlich, Langmuir and Temkin isotherm models. Langmuir isotherm has good agreement with R-2 value over 0.99. Pseudo second order model was fitted for this adsorption system. Here we showed that 99% removal of MB can be achieved with Amberlite XAD-16. SEM studies revealed the morphological observations of the unloaded adsorbent and the changes in the adsorbed polymeric resin. FTIR spectrums of adsorbents before and after the adsorption supported the SEM results.Öğe Correlations For Estimating Diesel Oil Properties from Component Data(Beykent Üniversitesi, 2009) Yorulmaz, Yavuz; Uslu, HasanDiesel oil stocks obtained from light and heavy Saudi Arabian crude oils were analyzed for their physical properties. By blending these component stocks in various ratios, final diesel oil products were obtained and correlations for the prediction of properties of final blends were developed with the help of multiple analysis technique on component data. The results produced from these correlations were compared with the actual laboratory data and good agreements supporting the correlations were observed.Öğe Distribution of Gibberellic Acid from the Aqueous Phase to the Organic Phase(Amer Chemical Soc, 2012) Uslu, HasanThe reactive extraction of gibberellic acid (GA) using tricaprylmethylammonium chloride (Aliquat 336) diluted in three different alcohols, three different esters, and two different ketones were used to explore the effect of diluent on the gibberellic acid extraction. Experimental measurements have been carried out at T/K = 298.15. The loading ratio (Z), extraction efficiency (E), and distribution coefficients (K-D) have been computed. The greatest extraction efficiency has been a value of 79 % for isoamyl alcohol. The linear solvation energy relationship (LSER) model has been fitted for the experimental values of alcohols. The LSER model gives close results to experimental data; R-2 is 0.991.Öğe Distribution of Penicillin G from the Aqueous Phase to the Organic Phase Using Amberlite LA-2 Extractant in Different Diluents(Amer Chemical Soc, 2014) Uslu, Hasan; Gunyeli, Seyhan; Ilbay, Zeynep; Kirbaslar, S. IsmailBenzyl penicillin, known as penicillin G (PG), is a beta-lactam antibiotic and also a weak monocarboxylic acid. The penicillin G extraction from aqueous solution by Amberlite LA-2 in different diluents, that is, octan-1-ol, nonan-1-ol, 3-methyl-1-butanol, ethyl ethanoate, propyl ethanoate, 4-methylpentan-2-one, octan-2-one, octane, and decane has been studied. According to experimental results, some thermodynamic parameters, such as distribution coefficients (K-D), loading factors (Z), and the extraction efficiency or degree (E), were calculated. The best extraction efficiency, distribution coefficient, and loading factor were determined using 3-methyl-1-butanol diluent as values of 92.63, 12.25, and 0.195, respectively. The linear solvation energy relationship (LSER) model was regressed for the experimental results of the distribution coefficient with the regression coefficient (R-2) as 0.96. Besides, the equilibrium model for the extraction degree of alcohols has been applied and compared with experimental data.Öğe Effect of binary extractants and modifier-diluents systems on equilbria of propionic acid extraction(Elsevier, 2009) Keshav, Amit; Wasewar, Kailas L.; Chand, Shri; Uslu, HasanPropionic acid is an important carboxylic acid widely used in chemical industries. The recovery from aqueous waste streams and fermentation broth is of research interest. Extraction of carboxylic acids by reactive extraction using extractant-diluent, mixed extractants in diluents and extractants in mixed diluents etc. are emerging areas of study. With this aim reactive extraction of propionic acid was carried out to study: (i) effect of binary extractants (tri-n-octylamine(TOA):tri-n-butylphosphate (TBP), TOA:Aliquat 336 and TBP:Aliquar 336), (ii) effect of modifier (1-decanol) in different diluents (kerosene, n-octane. n-heptane. petroleum ether, butyl acetate, MIBK. 2-octanol. dodecanol, hexane) and (iii) effect of phase volume. Improved extractions using binary extractants and binary diluents were observed. Since liquid-liquid extraction is dependent on effect of modifier concentration, effect of phase volume, presence of single or binary extractants and binary diluents, the Study will be useful in the design of reactive extraction process for propionic acid recovery. (C) 2008 Elsevier B.V. All rights reserved.Öğe Effect of Diluent on the Extraction of Oxoethanoic (Glyoxylic) Acid by N,N-Dioctyloctan-1-amine (TOA)(Amer Chemical Soc, 2011) Pehlivanoglu, Nil; Uslu, Hasan; Kirbaslar, S. IsmailThe extractability of aqueous solutions of oxoethanoic acid by N,N-dioctyloctan-1-amine (TOA) in various diluents, including isoamyl alcohol, octan-1-ol, nonan-1-ol, decan-1-ol, methyl ethyl ketone, diisobuthyl ketone, hexan-2-one, toluene, kerosene, and n-hexane has been investigated. Batch extraction results at 25 degrees C have been calculated and reported as distribution coefficients (K-D), loading factors (Z), and extraction efficiencies (E). With these solvents, using TOA has been found to be very effective (K-D >> 1). Decan-1-ol was found to be the most effective diluent with the highest value of K-D (13.43) at 1.37 mol.kg(-1) concentration of TOA. The results of the liquid-liquid equilibrium measurements were correlated with a linear solvation energy relationship (LSER) model that takes into account physical interactions as well as with modified Freundlich and Langmuir equations. The experimental results for the oxoethanoic acid extraction are compared to the model results.Öğe Effect of Diluents on the Extraction of Fumaric Acid by Tridodecyl Amine (TDA)(Amer Chemical Soc, 2015) Gemici, Aysegul; Uslu, Hasan; Gok, Asli; Kirbaslar, S. IsmailSeparation of fumaric acid from aqueous media with tridodecyl amine (TDA), which is a long chain aliphatic amine, was carried out at 298 K. Different categories of diluents, ketones (methyl iso butyl ketone (MIBK), 2-heptanone, and 2-octanone) and alcohols (isoamyl alcohol, 1-octanol) and 1-decanoL) were used to dissolve TDA. Distribution coefficients (K-D), extraction efficiency (E), and loading factors (Z) were obtained as a function a experimental results. The most operative diluent was determined as heptan-2-one with the highest distribution coefffdent (KD) value of 26.00. In additional to experimental studies, the linear solvation energy relationship (LSER) modeling with included Hidebrand Hansen solubility parameters was applied for alcoholic diluents. Predicted data by LSER gave good agreement with experimental data.Öğe Effect of Solvent and pH on the Extraction of Carbolic Acid from Aqueous Solution by TOMAC(Amer Chemical Soc, 2016) Uslu, Hasan; Bamufleh, Hisham S.Studies on the extraction of carbolic acid (phenol) at different pHs by trioctyl methylammonium chloride (TOMAC) diluted in octane, decan, octan-1-ol, and decan-1-ol are reported. Experimental results of batch extraction experiments are calculated and reported for distribution coefficients (Kip), loading factors (Z), and extraction efficiency (E). All measurements were carried out at 298.15 K. The maximum removal of phenol was observed to be 88.679% at pH = 5 for octan-1-ol. The results of the liquid liquid equilibrium measurements were correlated with a linear solvation energy relationship (LSER) model, which takes into account physical interactions. The remaining parameters were fitted to the experimental results. Experimental results for the liquid liquid equilibrium were compared to the model. The LSER model was applied to correlate experimental values.
