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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Nanoparticles,liquid-liquid extraction,Mass Transfer Coefficient,Hydrophilic,Hydrophobic
- چکیده:
- چکیده انگلیسی: In the present study, the effect of various nanofluids on mass transfer coefficients in an irregular packed liquid-liquid extraction column was investigated. The chemical system of toluene–acetic acid–water was used. 10 nm SiO2, TiO2 and ZrO2 nanoparticles with various concentrations were dispersed in toluene-acid acetic to provide nanofluids. The influence of concentration and hydrophobicity/hydrophilicity of nanoparticle on mass transfer coefficient was discussed. The experimental results show that the mass transfer coefficient enhancement depends on the kind and the concentration of nanoparticles. The maximum enhancement of 35%, 245% and 207% was achieved for 0.05 vol% of SiO2, TiO2 and ZrO2 nanofluids, respectively. A new conceptual model was proposed for prediction of the effective diffusivity as a function of nanoparticle concentration, drop size and drop Reynolds number.
- انتشار مقاله: 08-03-1396
- نویسندگان: Ali Vesal,Ahmad Rahbar-Kelishami,Toraj Mohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Isotherm,Malachite Green,Modified perlite
- چکیده:
- چکیده انگلیسی: Adsorption of malachite green (MG) from an aqueous solution onto unexpanded perlite (UP), expanded perlite (EP) and NaOH-modified unexpanded perlite (NaOH-UP) powders has been investigated. The effects of contact time, pH, initial dye concentration, adsorbent dosage and temperature have been evaluated. The adsorbents were characterized by Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The obtained results proved that the three examined powders can be used successfully for removal of MG from aqueous solutions as low cost mineral adsorbents. The maximum adsorption capacities of UP, EP and NaOH-UP were 23.81 mg/g, 29.41 mg/g and 39.68 mg/g, respectively. Kinetic studies show that the kinetics of the MG adsorption onto the adsorbents followed the second order model. The MG equilibrium adsorption data were best described by the Langmuir isotherm model for all adsorbents.
- انتشار مقاله: 26-01-1396
- نویسندگان: Elahe Rostami,Reza Norouzbeigi,Ahmad Rahbar-Kelishami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Kinetics,Taguchi Method,Crystal violet (CV+),Surfactant-modified dolomite
- چکیده:
- چکیده انگلیسی: This paper presents the adsorption of crystal violet (CV+) from aqueous solution on surfactant-modified dolomite. Liquid phase batch operations were carried out to observe the effect of various experimental parameters such as initial dye concentration, adsorbent dosage, pH and NaCl concentration. The optimum conditions for these parameters were calculated by Taguchi method. Equilibrium isotherm data were analyzed according to Langmuir, Freundlich and Temkin equations. The experimental data fitted well to Freundlich adsorption model. The maximum adsorption capacities by Langmuir analysis were determined to be 49.261mg/g at 22℃ that indicates suitable performance by of this adsorbent. The pPseudo-first-order and, pseudo-second-order kinetics and the intraparticle diffusion models were also evaluated for the adsorption of CV+ onto surfactant-modified dolomite. The positive value of free energy change confirmed the nature of physisorption of dye onto adsorbent.
- انتشار مقاله: 27-10-1395
- نویسندگان: Maryam Arabpour,Ahmad Rahbar-Kelishami,Reza Norouzbeigi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Membrane Science and Research
- نوع مقاله: Journal Article
- کلمات کلیدی: SLM,supported liquid membrane,Carrier,metal ion,Stripping phase,Feed phase
- چکیده:
- چکیده انگلیسی: Using liquid membrane and, in particular, supported liquid membrane (SLM) is a novel method of separation in comparison to other methods such as adsorption, extraction and ion exchange. SLM is a combination of simultaneous extraction and disposal whose high efciency and capability is proven by many studies. So far, many researchers have utilized SLM in various scientifc felds including analytical chemistry, organic and inorganic chemistry, chemical engineering, biotechnology and bio-pharmaceutics. Dynamic transfer, high selectivity, possibility of expensive carrier usage, low energy consumption and low operational costs are part of the advantages attributed to SLM. In the present paper, previous studies and the latest achievements in designing various modules for metal ions separation by SLM are reviewed.
- انتشار مقاله: 23-02-1396
- نویسندگان: Mohammad Amini,Ahmad Rahbar-Kelishami,Mohammad Alipour,Omid Vahidi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Pharmaceutical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Wastewater treatment,Amoxicillin,Solvent extraction,Pharmaceutical pollution,Response surface methodology, Environment
- چکیده:
- چکیده انگلیسی: In this study, extraction of amoxicillin (AMOX) ions from aqueous solution by liquid-liquid extraction (LLE) was investigated. The LLE process by response surface methodology (RSM) was carried out based on central composite design (CCD). The organic phase consisted of extractant and toluene as diluent. In this process, triethylamine (TEA), di-2-ethylhexyl phosphoric acid and mono-2-ethylhexyl phosphoric acid mixture (MDEHPA) were used as extractant. The process parameters such as extractant concentration, feed acidity, extraction time and effect of diluents were optimized. The contours and 3D response surfaces of AMOX extraction efficiency were obtained. The optimum conditions for the AMOX extraction using RSM for TEA were: feed pH 2.7, extractant concentration 12.9 %( V/V) and extraction time 19 min and for MDEHPA: feed pH 11, extractant concentration 12.3 %( V/V) and extraction time 21 min. At these condition the maximum AMOX extraction was found to be 93.5 % and 96 % using TEA and MDEHPA, respectively.
- انتشار مقاله: 10-04-1397
- نویسندگان: Zahra Seifollahi,Ali Abbasi,Ahmad Rahbar-Kelishami
- مشاهده