scholarly journals Adsorption of Aqueous As (III) in Presence of Coexisting Ions by a Green Fe-Modified W Zeolite

Water ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 281 ◽  
Author(s):  
Adriana Medina-Ramirez ◽  
Procoro Gamero-Melo ◽  
Beatriz Ruiz-Camacho ◽  
Jesus Isaac Minchaca-Mojica ◽  
Rafael Romero-Toledo ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Adsorption Process ◽  
Low Cost ◽  
Underground Water ◽  
Ferrous Chloride ◽  
Removal Capacity ◽  
Endothermic Process ◽  
Arsenite Removal ◽  
Ph Range ◽  
Coexisting Ions

The high toxicity of arsenite and the difficulty to remove it is one of the main challenges for water treatment. In the present work the surface of a low cost zeolite was modified by chemical treatment with a ferrous chloride to enhance its arsenite adsorption capacity. The effect of pH, ions coexistence, concentration, temperature and dosage was studied on the adsorption process. Additionally, the Fe-modified W zeolite was aged by an accelerated procedure and the regeneration of the exhausted zeolite was demonstrated. The Fe-modified W zeolite was stable in the pH range of 3 to 8 and no detriment to its arsenite removal capacity was observed in the presence of coexisting ions commonly found in underground water. The studies showed that the adsorption of As (III) on Fe-modified W zeolite is a feasible, spontaneous and endothermic process and it takes place by chemical bonding. The exhausting process proved the adsorption of 0.20 mg g−1 of As (III) by the Fe-modified W zeolite and this withstand at least five aging cycles without significant changes of its arsenite adsorption capacity. Fe-modified W zeolite prepared from fly ash might be a green and low-cost alternative for removal of As (III) from groundwater.

Cr(VI) Removal from Aqueous Solutions by Using Weak Base Epoxy Anion-Exchange Resin as Adsorbent

2012 ◽  
Vol 518-523 ◽  
pp. 2451-2455
Author(s):  
Hong Mei Ma ◽  
Zhi Liang Zhu ◽  
Yong Qian Cheng
Keyword(s):  
Anion Exchange ◽  
Adsorption Process ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Low Cost ◽  
Polluted Water ◽  
Weak Base ◽  
Freundlich Model ◽  
Ph Range ◽  
Coexisting Ions

In this study, 701 weak base epoxy anion-exchange resin was used as a low-cost adsorbent to remove Cr(V) from the light polluted water. To optimize its usage, the influences of pH, contact time, resin dosage and coexisting ions were investigated. Adsorption process was found to be highly pH dependent. The optimum pH range for adsorption of Cr(VI) was found to be between 6 and 8. The necessary time to reach adsorption equilibrium is about 20min. Langmuir and Freundlich adsorption isotherms were applicable to the adsorption process and their constants were evaluated. It was found that the Langmuir model yields a much better fit to the data compared with that of the Freundlich model.

scholarly journals Heavy metal removal from wastewater using various adsorbents: a review

2016 ◽  
Vol 7 (4) ◽  
pp. 387-419 ◽  
Author(s):  
Renu ◽  
Madhu Agarwal ◽  
K. Singh
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Aquatic Ecosystems ◽  
Adsorption Process ◽  
Metal Removal ◽  
Low Cost ◽  
Heavy Metal Removal ◽  
Review Article ◽  
Removal Capacity ◽  
Removal Of Heavy Metals

Heavy metals are discharged into water from various industries. They can be toxic or carcinogenic in nature and can cause severe problems for humans and aquatic ecosystems. Thus, the removal of heavy metals from wastewater is a serious problem. The adsorption process is widely used for the removal of heavy metals from wastewater because of its low cost, availability and eco-friendly nature. Both commercial adsorbents and bioadsorbents are used for the removal of heavy metals from wastewater, with high removal capacity. This review article aims to compile scattered information on the different adsorbents that are used for heavy metal removal and to provide information on the commercially available and natural bioadsorbents used for removal of chromium, cadmium and copper, in particular.

scholarly journals Removal of inorganic arsenic from aqueous solution by Fe-modified ceramsite: batch studies and remediation trials

2021 ◽  
Author(s):  
Yue Yin ◽  
Gaoyang Xu ◽  
Linlin Li ◽  
Chunlei Qiao ◽  
Yihua Xiao ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Adsorption Process ◽  
Low Cost ◽  
Stable State ◽  
Inorganic Arsenic ◽  
Kinetic Studies ◽  
Cost Effective ◽  
Aqueous System ◽  
Sediment Surface ◽  
Batch Studies

Abstract During sediment remediation, adsorbents addition is an effective technology for the removal of contaminants but the cost is often high. In this study, a low-cost adsorbent, ceramsite that made from contaminated riverbed sediment was synthesized. The Fe-modified ceramsite (FMC) was used as adsorbents to remove arsenate from aqueous solutions and reduce the inorganic arsenic release from contaminated sediments. Kinetic studies showed that chemisorption mainly governed the adsorption process while batch studies yielded theoretical adsorption capacity for arsenate of 10.63 mg/g at pH = 7 condition. Co-existing anions and pH have no significant impact on the adsorption process. In the regeneration studies, 91, 86, and 80% of the adsorption capacity were recovered in 3 cycles. In-situ remediation trials revealed that the addition of the adsorbent to sediment surface significantly reduced the release of inorganic arsenic into aqueous system, with a reduction efficiency of 86%. Furthermore, the species of the arsenic in the surface layer was significantly inactivated from an active state to a stable state. These findings highlight the application of the FMC as a facile and cost-effective adsorbent for containment of arsenic in solutions and sediments, demonstrating that they are highly applicable for practical cases.

scholarly journals Highly Effective Covalently Crosslinked Composite Alginate Cryogels for Cationic Dye Removal

Gels ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 178
Author(s):  
Serap Sezen ◽  
Vijay Kumar Thakur ◽  
Mehmet Murat Ozmen
Keyword(s):  
Adsorption Capacity ◽  
Dye Removal ◽  
Low Cost ◽  
Dye Adsorption ◽  
Maximum Adsorption Capacity ◽  
High Porosity ◽  
Order Model ◽  
Removal Capacity ◽  
Pseudo Second Order ◽  
The One

Currently, macroporous hydrogels have been receiving attention in wastewater treatment due to their unique structures. As a natural polymer, alginate is used to remove cationic dyes due to its sustainable features such as abundance, low cost, processability, and being environmentally friendly. Herein, alginate/montmorillonite composite macroporous hydrogels (cryogels) with high porosity, mechanical elasticity, and high adsorption yield for methylene blue (MB) were generated by the one-step cryogelation technique. These cryogels were synthesized by adding montmorillonite into gel precursor, followed by chemical cross-linking employing carbodiimide chemistry in a frozen state. The as-prepared adsorbents were analyzed by FT-IR, SEM, gel fraction, swelling, uniaxial compression, and MB adsorption tests. The results indicated that alginate/montmorillonite cryogels exhibited high gelation yield (up to 80%), colossal water uptake capacity, elasticity, and effective dye adsorption capacity (93.7%). Maximum adsorption capacity against MB was 559.94 mg g−1 by linear regression of Langmuir model onto experimental data. The Pseudo-Second-Order model was fitted better onto kinetic data compared to the Pseudo-First-Order model. Improved porosity and mechanical elasticity yielding enhanced dye removal capacity make them highly potential alternative adsorbents compared to available alginate/montmorillonite materials for MB removal.

scholarly journals Adsorption of U(VI) from Aqueous Solution onto Hydrotalcite-Like Compounds

2012 ◽  
Vol 9 (2) ◽  
pp. 669-679 ◽  
Author(s):  
Nguyen Van Suc
Keyword(s):  
Adsorption Capacity ◽  
Enthalpy Change ◽  
Time Dependent ◽  
Freundlich Isotherms ◽  
Langmuir And Freundlich Isotherms ◽  
Equilibrium Data ◽  
Endothermic Process ◽  
Ph Range ◽  
Initial Adsorption ◽  
Hydroxide Hydrate

Uranium adsorption by the synthesized compound of magnesium aluminum hydroxide hydrate – layered double hydrotalcite (STH)-like compounds was studied. The calcinated STH was proven to be a highly effective in U(VI) adsorption in pH range from 6.5 to 7. The time dependent experimental data were found to be fit to the pseudo-second-oder model. The equilibrium data have been modeled using Langmuir and Freundlich isotherms. The results showed that both model provide the best correlation with equilibrium data. The highest adsorption capacity, approximated 62.5 mg/g, was observed in the calcinated STH at 500 °C. The positive value of enthalpy change indicated that adsorption reaction of U(VI) on STH was endothermic process. The regeneration experiments of STH using 0.1M Na2CO3solution was successfully demonstrated multiple times without any significant effect on the initial adsorption capacity.

scholarly journals Equilibrium, Kinetic, and Thermodynamic Studies of Cationic Dyes Adsorption on Corn Stalks Modified by Citric Acid

2021 ◽  
Vol 5 (4) ◽  
pp. 52
Author(s):  
Liudmyla Soldatkina ◽  
Marianna Yanar
Keyword(s):  
Methylene Blue ◽  
Citric Acid ◽  
Adsorption Capacity ◽  
Malachite Green ◽  
Low Cost ◽  
Cationic Dyes ◽  
Thermodynamic Studies ◽  
Negative Results ◽  
Endothermic Process ◽  
Dyes Adsorption

The modification of agricultural wastes and their use as low-cost and efficient adsorbents is a prospective pathway that helps diminish waste and decrease environmental problems. In the present research, the natural adsorption capacity of corn stalks (CS) was improved by modification of their surface with citric acid. The adsorption capacity of the modified corn stalks (CS-C) was determined with the help of cationic dyes (methylene blue and malachite green). The equilibrium, kinetics, and thermodynamics of the cationic dyes on CS-C were studied. The Langmuir isotherm model best fitted the data both for methylene blue and malachite green adsorption on CS-C. The adsorption kinetics of the cationic dyes was well described by the pseudo-second order model. Thermodynamic studies revealed that adsorption of the cationic dyes on CS-C was an endothermic process. Negative results of ΔGo (between −31.8 and −26.3 kJ mol−1) indicated that the adsorption process was spontaneous in all the tested temperatures. The present study verified that citric acid-modified corn stalks can be used as a low-cost and effective adsorbent for removal of cationic dyes from aqueous solutions.

Kinetics and isotherm studies for the adsorption of phenol using low cost micro porous ZnCl2 activated coir pith carbonA paper submitted to the Journal of Environmental Engineering and Science.

2009 ◽  
Vol 36 (1) ◽  
pp. 148-159 ◽  
Author(s):  
R. Subha ◽  
C. Namasivayam
Keyword(s):  
Adsorption Process ◽  
Physical Adsorption ◽  
Low Cost ◽  
Ph Effect ◽  
Synthetic Wastewater ◽  
Isotherm Models ◽  
Langmuir Adsorption ◽  
Coir Pith ◽  
Endothermic Process ◽  
Efficient Adsorbent

In the present study, the potential of ZnCl2 activated coir pith carbon for adsorption of phenol from aqueous solution was investigated. Batch kinetics and isotherm studies were carried out to evaluate the effects of contact time, initial concentration, adsorbent dose, pH, and temperature. Adsorption kinetics was tested for first order, second order, and Bangham’s model and rate constants of kinetic models were evaluated. Equilibrium isotherms for the adsorption of phenol were analysed by Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherm models. The Langmuir adsorption capacity, Q0, was found to be 92.58 mg g–1 of the adsorbent. pH effect showed that physical adsorption might be involved in the adsorption process. Thermodynamic studies revealed that the adsorption of phenol by activated carbon was an endothermic process. The negative value of ΔG0 indicated the spontaneity of the adsorption process. Removal of phenol from synthetic wastewater was also tested. This study showed that ZnCl2 activated coir pith carbon could be used as an efficient adsorbent material for the removal of phenol from water.

scholarly journals Synthesis of Porous Boron-Doped Carbon Nitride: Adsorption Capacity and Photo-Regeneration Properties

2019 ◽  
Vol 16 (4) ◽  
pp. 581 ◽  
Author(s):  
Xiang Guo ◽  
Lei Rao ◽  
Peifang Wang ◽  
Lixin Zhang ◽  
Yuxiong Wang
Keyword(s):  
Adsorption Capacity ◽  
Carbon Nitride ◽  
Adsorption Process ◽  
Pollutant Removal ◽  
Practical Applications ◽  
Removal Capacity ◽  
Boron Doped ◽  
Powder Suspension ◽  
Photocatalytic Concrete ◽  
Excellent Stability

Carbon nitride (CN) with improved adsorption–degradation capacity was synthesized using B2O3 and CN via calcination. The pollutant removal capacity of this B2O3/CN (B-CN) was studied by a powder suspension experiment and added into concrete to evaluate the adsorption and degradation of methylene blue (MB). The characterizations of all samples indicate that B2O3 significantly affects CN, e.g., by increasing the CN specific surface area to 3.6 times the original value, extending visible light adsorption, and narrowing the band gap from 2.56 eV to 2.42 eV. Furthermore, the results show that B-CN composite materials have a higher MB-removal efficiency, with the adsorption capacity reaching 43.11 mg/g, which is about 3.3 times that of pristine CN. The MB adsorption process on B2-CN is mainly via electrostatic attraction and π–π interactions. In addition, B-CN added into concrete also has good performance. After five adsorption–degradation cycles, B-CN and photocatalytic concrete still exhibit a good regenerate ability and excellent stability, which are very important for practical applications.

scholarly journals PREPARACIÓN DE FILTROS DE ADSORCIÓN A BASE DE ARCILLAS MODIFICADAS

2019 ◽  
pp. 18-21
Keyword(s):  
Methylene Blue ◽  
Rhodamine B ◽  
Adsorption Process ◽  
Low Cost ◽  
Industrial Effluents ◽  
Low Degree ◽  
Natural Clays ◽  
Ph Range ◽  
Red Dye ◽  
Acid Red G

PREPARACIÓN DE FILTROS DE ADSORCIÓN A BASE DE ARCILLAS MODIFICADAS PREPARATION OF FILTERS ADSORPTION-BASED MODIFIED CLAYS María del Rosario Sun Kou, José Inga, Abel Gutarra DOI: https://doi.org/10.33017/RevECIPeru2007.0005/ RESUMEN La cantidad de contaminantes textiles (colorantes, surfactantes, fenoles entre otros) se ha incrementado en los últimos años en el Perú debido al aumento en los volúmenes de exportación, La adsorción es uno de los métodos más ampliamente usados para minimizar el grado de contaminación en los efluentes industriales, esto a motivado el desarrollo de materiales abundantes y de bajo costo que puedan ser utilizados como adsorbentes. Para este trabajo se ha empleado bentonitas peruanas, sódicas (LI-01 y LI-03) y cálcicas (HU-01 y HU-02), modificadas por termoactivación con HCl y H2SO4. Estos materiales fueron probados en la adsorción de diferentes colorantes: Rojo 80, Rhodamine B, rojo ácido G, azul de metileno. Comparada con la arcilla natural, la muestra termoactivada LI-03 incrementó su poder de adsorción en 13 veces, mientras la muestra HU-01 el incremento fue de 11 veces. El proceso de adsorción se produjo a pH entre 3 y 4 y cuando fue adicionado electrolitos a la solución coloreada.El mejor método encontrado para la preparación de los filtros de adsorción a base de arcillas termoactivadas fue el de la esponja polimérica con tratamientos térmicos entre 500 a 980°C. Los filtros preparados adsorbieron el 100% del colorante Rhodamine B y del azul de metileno. La adsorción se logró en menor grado con los colorantes rojo 80 y rojo ácido G. Palabras claves: adsorción, filtros de adsorción, arcillas termoactivadas, colorantes textiles. ABSTRACT During the last years in Perú the amount of textile contamination (dyes, surfactants, phenols among others) has increased due to the increase in export volumes.Adsorption is one of the methods most often used to minimize the grade of contamination in industrial effluents, and it has encouraged the development of abundant materials wich are low cost and so they could be used as adsorbents. For this work has been used peruvian bentonites, sodium (LI-01 and LI-03) and calcium (HU-01 and HU-02), modified by thermo-activation with HCl and H2SO4. These materials were tested in the adsorption of several dyes: Red 80, Rhodamine B, Acid Red G, methylene blue. A sample of thermo-activated LI-03 increased its power of adsorption thirteen times compared with the natural clays, on the other hand in the case of HU-01 increase was eleven times. The adsorption process is produced in pH range of 3 - 4 when electrolytes were added into dye solution.The best method found for the preparation of filters of adsorption from thermo-activated clays was the polymer sponge with thermic treatment in the range of 500 - 980ºC. Prepared filters adsorbed 100% of dyes: Rhodamine B and Methylene Blue. The adsorption got in low degree with Red dye 80 and Acid Red G. Keywords: Adsorption, filters of adsorption, thermo-activated clays, textile dyes.

scholarly journals Adsorption of lead (II) ions onto diatomite from aqueous solution: Mechanism, isotherm and kinetic studies

2015 ◽  
Vol 18 (1) ◽  
pp. 1-10 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Low Cost ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Freundlich Model ◽  
Ph Range ◽  
Solution Mechanism ◽  
Order Kinetic Equation

<div> <p>This study presents an evaluation of diatomite as a low cost adsorbent for Pb (II) removal from aqueous solutions under various conditions. The results demonstrate that adsorption of Pb (II) is strongly dependent on the pH of the solution. The effect of pH on adsorption of Pb (II) on diatomite was studied by varying pH from 2 to 12 at 20 <sup>o</sup>C. In the pH range of 2.0-4.0, the percentage of Pb (II) adsorbed increases slightly as the pH increases. At pH&gt;4, the percentage of Pb (II) adsorbed decreases with increasing pH because hydrolysis and precipitation begin to play an important role in the sorption of Pb (II). At pH 4, the maximum adsorption capacity of diatomite was found to be 26 mg/g. The adsorption isotherms of Pb (II) on diatomite can be described well by the Freundlich model. The regression equation coefficients were calculated and the data fitted to a second-order kinetic equation for removal of Pb (II) ions. The high adsorption capacity of diatomite makes it a suitable low-cost material for the removal of Pb (II) from aqueous solutions.</p> </div> <p>&nbsp;</p>

Sign in / Sign up

Export Citation Format

Share Document