scholarly journals Behaviour of Silica and Florisil as Solid Supports in the Removal Process of As(V) from Aqueous Solutions

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Andreea Gabor ◽  
Corneliu Mircea Davidescu ◽  
Adina Negrea ◽  
Mihaela Ciopec ◽  
Lavinia Lupa

In this study two solid supports, silica and florisil, were impregnated with crown ether (dibenzo-18-crown-6) and Fe(III) ions and their efficiency was compared in the adsorption process of As(V) from aqueous solutions. The solid supports were impregnated with crown ether due to their ability to build complexes with positives ions. Fe(III) was used because of As(V) affinity for it. The impregnated solid supports were characterized by energy dispersive X-ray analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, and the specific surface area. The influence of the solid : liquid ratio on the adsorption process, kinetic studies for the pseudo-first-order and pseudo-second-order, and activation energy were studied. Thermodynamic studies as well as equilibrium studies were carried out. The obtained results showed that, from the two considered materials, impregnated silica presents a higher efficiency with a good selectivity, able to remove As(V) from aqueous solutions containing trace concentrations.

2018 ◽  
Vol 156 ◽  
pp. 02012 ◽  
Author(s):  
Mardiah ◽  
Rif’an Fathoni ◽  
Pratiwi Pudyaningtyas ◽  
Hamdania Gamu ◽  
Rinaldy

High Consumption of paper, bring the impact of the waste paper itself. And the utilization of the paper is limited to recycled products and crafts, whereas paper such as newspaper still contains cellulose that can be potential to be used as a heavy metal adsorbent. In this study, newspaper was dissolved in sodium bicarbonate to reduce various impurities and then was reacted with citric acid (CA). The modified adsorbent was characterized by FTIR and was tested for adsorb Cu(II) in artificial solution. After adsorption process, the solution was filtered and analysed using Atomic Absorption Spectrophotometer (AAS). The adsorption experimental data was fitted to Langmuir, Freundlich, Tempkin, and Dubinin-Radushkevich for equilibrium model and was fitted to pseudo first order reaction and pseudo second order reaction for kinetic studies. The result showed that CA-modification newspaper able to remove heavy metals Cu(II) in solution.


2017 ◽  
Vol 77 (1) ◽  
pp. 60-69 ◽  
Author(s):  
Asma Aid ◽  
Samira Amokrane ◽  
Djamel Nibou ◽  
Elhadj Mekatel ◽  
Mohamed Trari ◽  
...  

Abstract The marine biomass Ulva compressa L. (ECL) was used as a low-cost biosorbent for the removal of Cr(VI) from contaminated aqueous solutions. The operating variables were optimized: pH ∼ 2, initial concentration of 25 mg/L, solid/liquid ratio of 6 g/L and a temperature of 50 °C, leading to an uptake elimination of 96%. A full factorial experimental design technique enabled us to obtain a mathematical model describing the Cr(VI) biosorption and to study the main effects and interactions among operational parameters. The equilibrium isotherm was analyzed by the Langmuir, Freundlich and Dubinin–Radushkevich (D-R) models; it has been found that the adsorption process follows well the Langmuir model. Kinetic studies showed that the pseudo-second order model describes suitably the experimental data. The thermodynamic parameters indicated an endothermic heat and a spontaneity of the Cr(VI) biosorption onto ECL.


2017 ◽  
Vol 76 (12) ◽  
pp. 3379-3391 ◽  
Author(s):  
Leticia Belén Escudero ◽  
Patricia Nora Smichowski ◽  
Guilherme Luiz Dotto

Abstract In the present work, Iridaea cordata (IC), a red marine macroalgae, was used as an efficient biosorbent for the removal of crystal violet (CV) and methylene blue (MB) dyes from aqueous solutions. The effects of pH (5, 7, and 9) and IC concentration (1, 3, and 5 g L−1) on the biosorption were studied through a 32 full factorial design. Under the optimal conditions (pH: 7, biosorbent concentration: 1 g L−1), biosorption kinetic studies were developed and the obtained experimental data were evaluated by pseudo-first order and pseudo-second order models. The results showed that the pseudo-second order model was in agreement with the experimental kinetic data for both dyes. Equilibrium studies were also carried out, and results exhibited good concordance with the Brunauer–Emmett–Teller isotherm. The biosorption capacities were 36.5 and 45.0 mg g−1 for CV and MB dyes, respectively. The dye removal percentages were around 75% for CV and 90% for MB. Thermodynamically, the biosorption process proved to be exothermic, spontaneous, and favorable. These results showed that IC biomass is a promising biosorbent for removal of CV and MB dyes from aqueous solutions.


2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Naser M. Alandis ◽  
Waffa Mekhamer ◽  
Omar Aldayel ◽  
Jameel A. A. Hefne ◽  
Manawwer Alam

The present work aims to investigate the ability of Saudi clay containing montmorillonite to remove Ag(I) and Cu(II) ions from aqueous solutions for waste water purification. The effect of pH, adsorbent mass, metal concentration, and contact time on the removal process has been investigated. The batch method was applied, using solution metal concentrations ranging from 40 to 2000 mg/L. Adsorption percentage and distribution coefficients (Kd) were determined as a function of metal concentration. pH 6 was found to be optimal for the adsorption. Adsorption reached equilibrium in 5 min for both Ag(I) and Cu(II) ions. The study on adsorption’s kinetic characteristics showed the adsorption process of these metal ions was of pseudo-second-order. Furthermore, the adsorption rate of Ag(I) was higher than that of Cu(II), and their adsorption appeared to follow the Langmuir isotherm. From the equilibrium studies, it was observed that the selectivity of Ag(I) was higher than that of Cu(II). The results showed that Saudi clay has the potential to be a suitable adsorbent for Ag(I) and Cu(II) removal from aqueous solutions compared with other adsorbents.


2010 ◽  
Vol 171-172 ◽  
pp. 15-18
Author(s):  
Zeng Quan Ji ◽  
Tian Hai Wang ◽  
Kai Hong Luo ◽  
Yao Qing Wang

An extracellular biopolymer (PFC02) produced by Pseudomonas alcaligenes was used as an alternative biosorbent to remove toxic Cd(II) metallic ions from aqueous solutions. The effect of experimental parameters such as pH, Cd(II) initial concentration and contact time on the adsorption was studied. It was found that pH played a major role in the adsorption process, the optimum pH for the removal of Cd(II) was 6.0. The FTIR spectra showed carboxyl, hydroxyl and amino groups of the PFC02 were involved in chemical interaction with the Cd(II) ions. Equilibrium studies showed that Cd(II) adsorption data followed Langmuir model. The maximum adsorption capacity (qmax) for Cd(II) ions was estimated to be 93.55 mg/g. The kinetic studies showed that the kinetic rates were best fitted to the pseudo-second-order model. The study suggestted that the novel extracellular biopolymer biosorbent have potential applications for removing Cd(II) from wastewater.


2016 ◽  
Vol 75 (1) ◽  
pp. 106-114 ◽  
Author(s):  
Lucas Meili ◽  
Társila Santos da Silva ◽  
Daniely Carlos Henrique ◽  
João Inácio Soletti ◽  
Sandra Helena Vieira de Carvalho ◽  
...  

In this work, the potential of ouricuri (Syagrus coronata) fiber as a novel biosorbent to remove methylene blue (MB) from aqueous solutions was investigated. The fiber was prepared and characterized according to the fundamental features for adsorption. A 23 experimental design was used to evaluate the effects of adsorbent dosage (M), fiber diameter (D) and agitation (A) on the adsorption capacity. In the more adequate conditions, kinetic and equilibrium studies were performed. The experimental design results showed that M = 10 g L−1), D = 0.595 mm and A = 200 rpm were the more adequate conditions for MB adsorption. Based on the kinetic study, it was found that the adsorption process was fast, being the equilibrium was attained at about 5 min, with 90% of color removal. The isotherm was properly represented by the Sips model, and the maximum adsorption capacity was 31.7 mg g−1. In brief, it was demonstrated that ouricuri fiber is an alternative biosorbent to remove MB from aqueous media, taking into account the process efficiency and economic viewpoint.


2017 ◽  
Vol 2 (1) ◽  
pp. 13-26
Author(s):  
Tengku Khamanur Azma Tg. Mohd Zamri ◽  
Mimi Sakinah Abd Munaim ◽  
Zularisam Ab Wahid

Natural dye extracted from the rhizome of Curcuma longa L. were applied to bamboo yarns using exhaustion dyeing process. This study investigates the dyeing behaviour of Curcumin; the major color component isolated from rhizomes of Curcuma longa L.on bamboo yarn. Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich isotherm models were used to test the adsorption process of curcumin on bamboo yarn. Comparison of regression coefficient value indicated that the Freundlich isotherm most fitted to the adsorption of curcumin onto bamboo yarn. Furthermore, the kinetics study on this research fitted the pseudo-second order model which indicates that the basis of interaction was chemical adsorption.


2020 ◽  
Vol 1 (2) ◽  
pp. 54-62
Author(s):  
Naser Al Amery ◽  
Hussein Rasool Abid ◽  
Shaobin Wang ◽  
Shaomin Liu

In this study, two improved versions of UiO-66 were successfully synthesised. Modified UiO-66 and UiO-66-Ce were characterised to confirm the integrity of the structure, the stability of functional groups on the surface and the thermal stability. Activated samples were used for removal harmful anionic dye (methyl orange) (MO) from wastewater. Batch adsorption process was relied to investigate the competition between those MOFs for removing MO from aqueous solution. Based on the results, at a higher initial concentration, the maximum MO uptake was achieved by UiO-66-Ce which was better than modified-UiO-66. They adsorbed 71.5 and 62.5 mg g-1 respectively. Langmuir and Freundlich isotherms were employed to simulate the experimental data. In addition, Pseudo first order and Pseudo second order equations were used to describe the dynamic behaviour of MO through the adsorption process. The high adsorption capacities on these adsorbents can make them promised adsorbents in industrial areas.


Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2218 ◽  
Author(s):  
Carlos Grande-Tovar ◽  
William Vallejo ◽  
Fabio Zuluaga

In this work, we synthesized chitosan grafted-polyacrylic acid (CS-g-PA) through surface-initiated atom transfer radical polymerization (SI-ATRP). We also studied the adsorption process of copper and lead ions onto the CS-g-PA surface. Adsorption equilibrium studies indicated that pH 4.0 was the best pH for the adsorption process and the maximum adsorption capacity over CS-g-PA for Pb2+ ions was 98 mg·g−1 and for Cu2+ it was 164 mg·g−1, while for chitosan alone (CS), the Pb2+ adsorption capacity was only 14.8 mg·g−1 and for Cu2+ it was 140 mg·g−1. Furthermore, the adsorption studies indicated that Langmuir model describes all the experimental data and besides, pseudo-second-order model was suitable to describe kinetic results for the adsorption process, demonstrating a larger kinetic constant of the process was larger for Pb2+ than Cu2+. Compared to other adsorbents reported, CS-g-PA had comparable or even superior adsorbent capacity and besides, all these results suggest that the new CS-g-PA polymers had potential as an adsorbent for hazardous and toxic metal ions produced by different industries.


2020 ◽  
Vol 168 ◽  
pp. 00026
Author(s):  
Liliia Frolova ◽  
Mykola Kharytonov ◽  
Iryna Klimkina ◽  
Oleksandr Kovrov ◽  
Andrii Koveria

Plasma method is used to synthesize manganese ferrite. The basic properties of ferrite are determined by IR spectroscopy, UV spectroscopy, X-ray phase analysis, vibration magnetometry. The paper shows that the use of magnetically controlled sorbent allows to purify waste waters from chromium (III). The process of adsorption of chromium cations (III) is investigated. The kinetics of the process is studied. To describe the equilibrium isotherms, the experimental data are analysed by the models of Langmuir, Freundlich isotherms. Pseudo-first order, pseudo-second-order, and Weber-Morris are used to elucidate the kinetic parameters and mechanism of the adsorption process. It has been established that the removal of Cr (III) cations is described by the pseudo-second order of the Langmuir reaction and mechanism.


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