scholarly journals Synthesis and Characterization of Porous Magnetite Nanosphere Iron Oxide as a Novel Adsorbent of Anionic Dyes Removal from Aqueous Solution

2021 ◽  
Vol 11 (5) ◽  
pp. 13377-13401 ◽  
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
High Performance ◽  
Average Particle Size ◽  
Average Particle ◽  
Order Kinetic ◽  
Anionic Dyes ◽  
Solution Ph ◽  
Remazol Red

Porous magnetite Fe3O4 nanospheres (PMNs) are synthesized for removal from an aqueous solution of anionic dyes Acid Red 57 (AR57) and Remazol Red (RR) and are used as a high-performance adsorbent. Characterization of PMNs was carried out using various techniques, such as Fourier-transform infrared spectroscopy, the surface area measured by Brunauer Emmett-Teller (BET), and it was found 143.65m2g-1, and were spherical-shaped as determined by TEM. Surface modification was calculated using electron microscopy (SEM) scanning. The spherical morphology of the PMNs is very uniform, with an average particle size of ~25,84 nm in diameter. Variables such as initial pH, the dosage of adsorbent, contact time, and temperature were analyzed to find the optimal adsorption conditions for extracting Acid Red 57 (AR57) and Remazol Red (RR) from aqueous solutions. For respective AR57 and RR, the optimal pH for the extraction of the anionic dyes examined from water solutions was 3 and 4. The maximum adsorption potential expected for AR57 and RR dyes was 888.68 and 808.43 mgg−1, respectively. The effects of the initial solution pH, temperature, initial concentration, contact time, salinity, and dosing of PMNs were systematically analyzed. These dyes were suitable for acid pH adsorption, as the PMNs Zero-charge point (pHPZC) equals 4.3. Adsorption findings were based on the Langmuir, Freundlich, Dubinin – Radushkevich, and Temkin adsorption isotherms. The adsorption isotherm had been found to follow the Langmuir model for both dyes. The mean adsorption energy (Ea) is 20.24 and 31.3 kJmol−1 for AR57 and RR, respectively, indicating a chemisorption process. The adsorption kinetics had been found to follow the pseudo-second-order kinetic model. The adsorption process was verified to be endothermic and spontaneous by thermodynamic studies. Using ethanol as a solvent, it was also studied the process of desorption of the adsorbed anionic dyes.

scholarly journals Adsorption of methylene blue from aqueous solutions by pyrolusite ore

2018 ◽  
Vol 18 (44) ◽  
pp. 5-11 ◽  
Author(s):  
Nizamettin Demirkıran ◽  
G D Turhan Özdemir ◽  
M Saraç ◽  
M Dardağan
Keyword(s):  
Methylene Blue ◽  
Particle Size ◽  
Contact Time ◽  
Average Particle Size ◽  
Dye Adsorption ◽  
Blue Dye ◽  
Average Particle ◽  
Order Kinetic ◽  
Adsorbent Dosage ◽  
Initial Ph

In this study, the adsorption of methylene blue dye was examined by using pyrolusite ore as a low-cost alternative adsorbent source. Pyrolusite, which contains mainly MnO2, is a manganese ore. The effects of the initial concentration of dye, contact time, initial pH of solution, adsorbent dosage, stirring speed of solution, and average particle size of adsorbent on the adsorption of methylene blue were studied. It was found that the percentage of the adsorbed dye increased with increasing the amount of pyrolusite. While the initial dye concentration, initial pH, contact time, stirring speed, particle size, and adsorbent dosage were 25 ppm, 6, 90 min, 250 rpm, 63 µm, and 12 g/l, respectively, the efficiency of dye adsorption on pyrolusite ore was 99%. The isotherm and kinetic studies relating to this adsorption process were also made. It was found that the equilibrium data followed the Langmuir isotherm model while the kinetic of process could be described by the pseudo-second order kinetic model.

scholarly journals Equilibrium, Kinetics, and Thermodynamics of the Biosorption of Zn(II) from Aqueous Solution Using Powdered Cow Hooves

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Ilesanmi Osasona ◽  
Olubode O. Ajayi ◽  
Albert O. Adebayo
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Kinetic Equations ◽  
Mesh Size ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Solution Ph ◽  
Equilibrium Studies ◽  
Biosorption Process ◽  
Increase With Increase

The capability of cow hoof (CH) to remove Zn(II) from aqueous solution under the influence of sorbent size, solution pH, contact time, and sorbent dosage was investigated through batch studies. Equilibrium studies were conducted at three different temperatures (298, 308, and 318 K) by contacting different concentrations of Zn(II) solution with a known weight of cow hoof. The biosorption of Zn onto cow hoof was found to increase with increase in the mass of sorbent used while the biosorption efficiency was found to decrease with increase in sorbent particle size. The optimum conditions of pH 4 and contact time of 60 minutes were required for maximum removal of Zn(II) by cow hoof (mesh size 212 µm). The equilibrium data were modelled using Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models. The data were best fitted by Langmuir model. The kinetic data were analysed using Lagergren kinetic equations and these were well fitted by the pseudo-second-order kinetic model. The thermodynamic parameters showed that the biosorption process was feasible, spontaneous, and endothermic.

scholarly journals Adsorption Equilibrium for Heavy Metal Divalent Ions (Cu2+, Zn2+, and Cd2+) into Zirconium-Based Ferromagnetic Sorbent

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Agnes Yung Weng Lee ◽  
Soh Fong Lim ◽  
S. N. David Chua ◽  
Khairuddin Sanaullah ◽  
Rubiyah Baini ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Average Particle Size ◽  
Isotherm Models ◽  
Average Particle ◽  
Property A ◽  
Divalent Ions ◽  
Solution Ph

Zirconium-based ferromagnetic sorbent was fabricated by coprecipitation of Fe2+/Fe3+ salts in a zirconium solution and explored as a potential sorbent for removing the Cu2+, Zn2+, and Cd2+ from aqueous solution. The sorbent could easily be separated from aqueous solution under the influence of external magnetic field due to the ferromagnetism property. A trimodal distribution was obtained for the sorbent with average particle size of 22.74 μm. The –OH functional groups played an important role for efficient removal of divalent ions. The surface of the sorbent was rough with abundant protuberance while the existence of divalent ions on the sorbent surface after the sorption process was demonstrated. Decontamination of the heavy metal ions was studied as a function of initial metal ions concentration and solution pH. Uptake of the heavy metal ions showed a pH-dependent profile with maximum sorption at around pH 5. The presence of the ferromagnetic sorbent in solution at different initial pH has shown a buffering effect. Equilibrium isotherms were analyzed using Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherm models. Adequacy of fit for the isotherm models based on evaluation of R2 and ARE has revealed that heavy metal ions decontamination was fitted well with the Freundlich model.

scholarly journals Sumac Leaves as a Novel Low-Cost Adsorbent for Removal of Basic Dye from Aqueous Solution

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Öznur Dülger ◽  
Fatma Turak ◽  
Kadir Turhan ◽  
Mahmure Özgür
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Low Cost ◽  
Second Order ◽  
Initial Solution ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Solution Ph ◽  
Intraparticle Diffusion Model ◽  
Pseudo Second Order

Sumac Leaves (SL) (Rhus Coriaria L. ) were investigated as an inexpensive and effective adsorbent for the adsorption of methylene blue (MB) from aqueous solution. The effects of initial dye concentration, initial solution pH, phases contact time, and adsorbent dose on the adsorption of MB on SL were investigated. The amount of dye adsorbed was found to vary with initial solution pH, Sumac Leaves dose, MB concentration, and phases contact time. The Langmuir and Freundlich adsorption models were evaluated using the experimental data and the experimental results showed that the Langmuir model fits better than the Freundlich model. The maximum adsorption capacity was found to be 151.69 mg/g from the Langmuir isotherm model at 25°C. The value of the monolayer saturation capacity of SL was comparable to the adsorption capacities of some other adsorbent materials for MB. The adsorption rate data were analyzed according to the pseudo-first order kinetic and pseudo-second order kinetic models and intraparticle diffusion model. It was found that kinetic followed a pseudo-second order model.

Simultaneous removal of cationic methylene blue and anionic reactive red 198 dyes using magnetic activated carbon nanoparticles: equilibrium, and kinetics analysis

2018 ◽  
Vol 2017 (2) ◽  
pp. 534-545 ◽  
Author(s):  
Samer Abuzerr ◽  
Maher Darwish ◽  
Amir Hossein Mahvi
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
High Performance ◽  
Order Kinetic ◽  
Anionic Dyes ◽  
Solution Ph ◽  
Magnetic Activated Carbon ◽  
Reactive Red 198 ◽  
Equilibrium And Kinetics ◽  
Order Kinetic Model

Abstract For the simultaneous adsorption of cationic dye (methylene blue, MB) and anionic dye (reactive red 198, RR198) from aqueous solution, magnetic activated carbon (MAC) nanocomposite as a promising adsorbent was prepared and used. The concentration of MB at different time intervals was determined using a UV-Vis spectrophotometer while the concentration of RR198 was determined using a high performance liquid chromatography (HPLC) system. The effect of solution pH, contact time, adsorbent amount, and dye concentration were investigated. Also, both kinetic and isotherm experiments were studied. The optimum pH was 10 and 5.5 for adsorption of MB and RR198, respectively, and the equilibrium status was achieved after 120 min. The adsorption kinetics was controlled by the pseudo-second order kinetic model more than pseudo-first order. The best-fitted isotherms were Freundlich and Langmuir models for MB and RR198, respectively. The higher values of Freundlich adsorption capacity (Kf) for MB in comparison with RR198 refer to MAC affinity to remove cationic dyes more than anionic dyes. Apparently, there was no substantial change in the adsorption efficiency among the 10 adsorption–desorption cycles. Overall, MAC can be considered as an effective and efficient viable adsorbent for cationic and anionic dyes removal from industrial wastewaters.

Azithromycin nanosuspension preparation using evaporative precipitation into aqueous solution (EPAS) method and its comparative dissolution study

2020 ◽  
Vol 17 ◽  
Author(s):  
Mohammad Hossain Shariare ◽  
Tonmoy Kumar Mondal ◽  
Hani Alothaid ◽  
Md. Didaruzzaman Sohel ◽  
MD Wadud ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Dissolution Rate ◽  
Average Particle Size ◽  
Scale Up ◽  
Average Particle ◽  
Total Drug ◽  
Residual Solvent ◽  
Dissolution Study ◽  
Drug Content

Aim: EPAS (evaporative precipitation into aqueous solution) was used in the current studies to prepare azithromycin nanosuspensions and investigate the physicochemical characteristics for the nanosuspension batches with the aim of enhancing the dissolution rate of the nanopreparation to improve bioavailability. Methods: EPAS method used in this study for preparing azithromycin nanosuspension was achieved through developing an in-house instrumentation method. Particle size distribution was measured using Zetasizer Nano S without sample dilution. Dissolved azithromycin nanosuspensions were also compared with raw azithromycin powder and commercially available products. Total drug content of nanosuspension batches were measured using an Ultra-Performance Liquid Chromatography (UPLC) system with Photodiode Array (PDA) detector while residual solvent was measured using gas chromatography (GC). Results: The average particle size of azithromycin nanosuspension was 447.2 nm and total drug content was measured to be 97.81% upon recovery. Dissolution study data showed significant increase in dissolution rate for nanosuspension batch when compared to raw azithromycin and commercial version (microsuspension). The residual solvent found for azithromycin nanosuspension is 0.000098023 mg/ mL or 98.023 ppb. Conclusion: EPAS was successfully used to prepare azithromycin nanoparticles that exhibited significantly enhanced dissolution rate. Further studies are required to scale up the process and determine long term stability of the nanoparticles.

Synthesis and Characterization of Water-Soluble Monolayer-Protected Gold Nanoparticles

2011 ◽  
Vol 415-417 ◽  
pp. 617-620 ◽  
Author(s):  
Yan Su ◽  
Ying Yun Lin ◽  
Yu Li Fu ◽  
Fan Qian ◽  
Xiu Pei Yang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Gold Nanoparticles ◽  
Average Particle Size ◽  
Water Soluble ◽  
Synthesis And Characterization ◽  
Average Particle ◽  
Transmission Electron

Water-soluble gold nanoparticles (AuNPs) were prepared using 2-mercapto-4-methyl-5- thiazoleacetic acid (MMTA) as a stabilizing agent and sodium borohydride (NaBH4) as a reducing agent. The AuNPs product was analyzed by transmission electron microscopy (TEM), UV-vis absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR). The TEM image shows that the particles were well-dispersed and their average particle size is about 5 nm. The UV-vis absorption and FTIR spectra confirm that the MMTA-AuNPs was stabilized by the carboxylate ions present on the surface of the AuNPs.

scholarly journals Simultaneous removal of cationic and anionic dyes from aqueous solution by double functional groups modified bagasse

2020 ◽  
Vol 82 (10) ◽  
pp. 2159-2167
Author(s):  
Ru-yi Zhou ◽  
Jun-xia Yu ◽  
Ru-an Chi
Keyword(s):  
Aqueous Solution ◽  
Functional Groups ◽  
Order Kinetic ◽  
Anionic Dyes ◽  
Adsorption Capacities ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Amine Groups ◽  
Modified Adsorbents ◽  
Zeta Potential Analysis

Abstract Double functional groups modified bagasse (DFMBs), a series of new zwitterionic groups of carboxyl and amine modified adsorbents, were prepared through grafting tetraethylenepentamine (TEPA) onto the pyromellitic dianhydride (PMDA) modified bagasse using the DCC/DMAP method. DFMBs' ability to simultaneously remove basic magenta (BM, cationic dye) and Congo red (CR, anionic dye) from aqueous solution in single and binary dye systems was investigated. FTIR spectra and Zeta potential analysis results showed that PMDA and TEPA were successfully grafted onto the surface of bagasse, and the ratio of the amount of carboxyl groups and amine groups was controlled by the addition of a dosage of TEPA. Adsorption results showed that adsorption capacities of DFMBs for BM decreased while that for CR increased with the increase of the amount of TEPA in both single and binary dye systems, and BM or CR was absorbed on the modified biosorbents was mainly through electrostatic attraction and hydrogen bond. The adsorption for BM and CR could reach equilibrium within 300 min, both processes were fitted well by the pseudo-second-order kinetic model. The cationic and anionic dyes removal experiment in the binary system showed that DMFBs could be chosen as adsorbents to treat wastewater containing different ratios of cationic and anionic dyes.

scholarly journals Organic Dyes Adsorption on the Almond Shell (Prunus dulcis) as Agricultural Solid Waste from Aqueous Solution in Single and Binary Mixture Systems

2021 ◽  
Vol 12 (2) ◽  
pp. 2022-2040
Keyword(s):  
Aqueous Solution ◽  
Binary Mixture ◽  
Contact Time ◽  
Binary Systems ◽  
Organic Dyes ◽  
Low Cost ◽  
Kinetic Studies ◽  
Prunus Dulcis ◽  
Order Kinetic ◽  
Almond Shell

Almond shell (AS) is a low-cost adsorbent used in this study for the removal of methylene blue (MB), crystal violet (CV), and Congo red (CR) from an aqueous solution in single and mixture binary systems. The low-cost adsorbent was characterized by FTIR and SEM analysis. The effects of AS dose, contact time, initial dye concentration, pH, and temperature on MB, CV, and CR adsorption were studied in a single system. In a binary system, the MB, CV, and CR were removed from the mixture of MB+CR, CV+MB, and CV+CR with a percentage in volume ranging from 0 to 100 % in MB and CV, and CR. Kinetic studies showed rapid sorption following a second-order kinetic model with of contact time of 10 min. The modulation of adsorption isotherms showed that retention follows the Langmuir model. The thermodynamic parameters proved that the MB, CV, and CR adsorption process was feasible, spontaneous, and exothermic. The synergy adsorption between dyes in a binary mixture of MB+CR and CV+CR, while the competition adsorption between dyes in a binary mixture of MB+ CV.

scholarly journals Preparation and characterization of domperidone nanoparticles for dissolution improvement

2018 ◽  
Vol 27 (1) ◽  
pp. 39-52
Author(s):  
Mohammed Sabar Al-lami ◽  
Malath H. Oudah ◽  
Firas A. Rahi
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
In Vitro Release ◽  
Methyl Cellulose ◽  
Precipitation Method ◽  
Average Particle ◽  
Antisolvent Precipitation ◽  
Stirring Time

This study was carried out to prepare and characterize domperidone nanoparticles to enhance solubility and the release rate. Domperidone is practically insoluble in water and has low and an erratic bioavailability range from 13%-17%. The domperidone nanoparticles were prepared by solvent/antisolvent precipitation method at different polymer:drug ratios of 1:1 and 2:1 using different polymers and grades of poly vinyl pyrolidone, hydroxy propyl methyl cellulose and sodium carboxymethyl cellulose as stabilizers. The effect of polymer type, ratio of polymer:drug, solvent:antisolvent ratio, stirring rate and stirring time on the particle size, were investigated and found to have a significant (p? 0.05) effect on particle size. The best formula was obtained with lowest average particle size of 84.05. This formula was studied for compatibility by FTIR and DSC, surface morphology by FESEM and crystalline state by XRPD. Then domperidone nanoparticles were formulated into a simple capsule dosage form in order to study of the in vitro release of drug from nanoparticles in comparison raw drug and mixture of polymer:drug ratios of 2:1. The release of domperidone from best formula was highly improved with a significant (p? 0.05) increase.

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