Synthesis of Magnetic Adsorbents Based Carbon Highly Efficient and Stable for Use in the Removal of Pb(II) and Cd(II) in Aqueous Solution

In this study, two alternative synthesis routes for magnetic adsorbents were evaluated to remove Pb(II) and Cd(II) in an aqueous solution. First, activated carbon was prepared from argan shells (C). One portion was doped with magnetite (Fe3O4+C) and the other with cobalt ferrite (CoFe2O4+C). Characterization studies showed that C has a high surface area (1635 m2 g−1) due to the development of microporosity. For Fe3O4+C the magnetic particles were nano-sized and penetrated the material’s texture, saturating the micropores. In contrast, CoFe2O4+C conserves the mesoporosity developed because most of the cobalt ferrite particles adhered to the exposed surface of the material. The adsorption capacity for Pb(II) was 389 mg g−1 (1.88 mmol g−1) and 249 mg g−1 (1.20 mmol g−1); while for Cd(II) was 269 mg g−1 (2.39 mmol g−1) and 264 mg g−1 (2.35 mmol g−1) for the Fe3O4+C and CoFe2O4+C, respectively. The predominant adsorption mechanism is the interaction between -FeOH groups with the cations in the solution, which are the main reason these adsorption capacities remain high in repeated adsorption cycles after regeneration with HNO3. The results obtained are superior to studies previously reported in the literature, making these new materials a promising alternative for large-scale wastewater treatment processes using batch-type reactors.

Download Full-text

Synthesis of Silver-Impregnated Magnetite Mesoporous Silica Composites for Removing Iodide in Aqueous Solution

Toxics ◽

10.3390/toxics9080175 ◽

2021 ◽

Vol 9 (8) ◽

pp. 175

Author(s):

Sang-Eun Jo ◽

Jung-Weon Choi ◽

Sang-June Choi

Keyword(s):

Aqueous Solution ◽

Langmuir Isotherm ◽

High Surface ◽

High Surface Area ◽

High Capacity ◽

Maximum Adsorption Capacity ◽

Initial Contact ◽

Order Kinetic ◽

Sorption Ability ◽

High Sorption

Mag@silica-Ag composite has a high sorption ability for I− in aqueous solution due to its high surface area and strong affinity for the studied anion. The material adsorbed I− rapidly during the initial contact time (in 45 min, η = 80%) and reached adsorption equilibrium after 2 h. Moreover, mag@silica-Ag proved to selectively remove I− from a mixture of Cl−, NO3− and I−. The adsorption behavior fitted the Langmuir isotherm perfectly and the pseudo-second-order kinetic model. Based on the Langmuir isotherm, the maximum adsorption capacity of mag@silica-Ag was 0.82 mmol/g, which is significantly higher than previously developed adsorbents. This study introduces a practical application of a high-capacity adsorbent in removing radioactive I− from wastewaters.

Download Full-text

High Cr(VI) Adsorption Performance of Coal-Based Activated Carbon in Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.798-799.1123 ◽

2013 ◽

Vol 798-799 ◽

pp. 1123-1127

Author(s):

Hua Lei Zhou ◽

Qiong Qiong Zhu ◽

Dong Hua Huang

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Pore Structure ◽

Ph Value ◽

High Surface ◽

High Surface Area ◽

Koh Activation ◽

Transmission Electron ◽

Mesoporous Adsorbent ◽

Initial Ph

The activated carbon with high surface area was prepared by KOH activation from anthracite and used as adsorbent for removal of Cr (VI) from aqueous solution. The pore structure and surface properties were characterized by N2 adsorption at 77K, transmission electron microscope (TEM) and Fourier transform infrared spectroscopy ( FTIR). Effect of pH and isotherms at different temperature were investigated. Results show that the prepared carbon is a microporous-and mesoporous-adsorbent with developed pore structure and abundant surface oxygen-containing groups. PH value of the solution plays key function on the adsorption. The chemical adsorption dominates the adsorption process. The activated carbon exhibits much higher Cr adsorption capacity than the commercial activated carbon at initial pH of ~3. The equilibrium adsorption data are fitted by both Freundlich model and Langmuir model well.

Download Full-text

Facile and large-scale synthesis of poly(m-phenylenediamine) nanobelts with high surface area and superior dye adsorption ability

RSC Advances ◽

10.1039/c4ra06553k ◽

2014 ◽

Vol 4 (85) ◽

pp. 45244-45250 ◽

Cited By ~ 15

Author(s):

Yun Meng ◽

Liyuan Zhang ◽

Liyuan Chai ◽

Wanting Yu ◽

Ting Wang ◽

...

Keyword(s):

Surface Area ◽

Large Scale ◽

High Surface ◽

High Surface Area ◽

Dye Adsorption ◽

High Adsorption ◽

Adsorption Ability ◽

Adsorption Performance ◽

Large Scale Synthesis

PmPD nanobelts with high adsorption performance have been synthesized by using CTAP as oxidants.

Download Full-text

Adsorption of Mn2+ from Aqueous Solution Using Manganese Oxide-Coated Hollow Polymethylmethacrylate Microspheres (MHPM)

Adsorption Science & Technology ◽

10.1155/2021/5597299 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Dhiraj Dutta ◽

Jyoti Prasad Borah ◽

Amrit Puzari

Keyword(s):

Aqueous Solution ◽

Manganese Oxide ◽

Adsorption Capacity ◽

High Surface ◽

High Surface Area ◽

Freundlich Isotherm ◽

Ion Concentration ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

Coated Sand

Results of investigation on adsorption of Mn2+ from aqueous solution by manganese oxide-coated hollow polymethylmethacrylate microspheres (MHPM) are reported here. This is the first report on Mn-coated hollow polymer as a substitute for widely used materials like green sand or MN-coated sand. Hollow polymethylmethacrylate (HPM) was prepared by using a literature procedure. Manganese oxide (MnO) was coated on the surface of HPM (MHPM) by using the electroless plating technique. The HPM and MHPM were characterized by using optical microscopy (OM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Optical and scanning micrographs were used to monitor the surface properties of the coated layer which revealed the presence of MnO on the surface of HPM. TGA showed the presence of 4-5% of MnO in MHPM. Adsorption isotherm studies were carried out as a function of pH, initial ion concentration, and contact time, to determine the adsorption efficiency for removal of Mn2+ from contaminated water by the synthesized MHPM. The isotherm results showed that the maximum adsorption capacity of MnO-coated HPM to remove manganese contaminants from water is 8.373 mg/g. The obtained R 2 values of Langmuir isotherm and Freundlich isotherm models were 1 and 0.87, respectively. Therefore, R 2 magnitude confirmed that the Langmuir model is best suited for Mn2+ adsorption by a monolayer of MHPM adsorbent. The material developed shows higher adsorption capacity even at a higher concentration of solute ions, which is not usually observed with similar materials of this kind. Overall findings indicate that MHPM is a very potential lightweight adsorbent for removal of Mn2+ from the aqueous solution because of its low density and high surface area.

Download Full-text

Green and facile synthesis of cerium doped Ni3Fe electrocatalyst for efficient oxygen evolution reaction

Bulletin of the Chemical Society of Ethiopia ◽

10.4314/bcse.v34i2.12 ◽

2020 ◽

Vol 34 (2) ◽

pp. 353-363

Author(s):

F. Kanwal ◽

A. Batool ◽

R. Akbar ◽

S. Asim ◽

M. Saleem

Keyword(s):

Oxygen Evolution ◽

Oxygen Evolution Reaction ◽

Large Scale ◽

Low Cost ◽

High Surface ◽

High Surface Area ◽

Three Dimensional ◽

Alkaline Electrolyte ◽

Hydrogen Electrode ◽

Molar Ratios

Electrochemical water splitting is the most promising pathway to produce high-purity hydrogen to alleviate global energy crisis. This reaction demands inexpensive, efficient and robust electrocatalyst for its commercial use. Herein, we demonstrate an effective, facile and scalable method for the synthesis of cerium doped Ni3Fe nanostructures as an electrocatalyst for oxygen evolution reaction (OER) by following simple chemical bath deposition route. The different molar ratios (3, 6 and 12 mM) of cerium in the chemical bath were used to study its effect on the structural and the electrochemical properties of the Ni3Fe nanostructured films. Doping of cerium contents induced variations in the morphology of deposited Ni3Fe nanostructures. The optimized electrocatalyst Ni3Fe/Ce-6 yielded high surface area catalyst nanosheets uniformly deposited on three-dimensional conductive scaffold to ensure increase in the exposure of doped Ni3Fe catalytic sites with high electrical conductivity. As a result, this earth-abundant electrocatalyst affords high OER performance with a small overpotential of 310 mV versus reversible hydrogen electrode (RHE) at 10 mA cm-2 and retains good stability up to ~ 10 h in alkaline electrolyte. This scalable strategy has great potential in future advancement of efficient and low-cost electrocatalysts for their large-scale application in energy conversion systems. KEY WORDS: Oxygen evolution, Electrocatalyst, Ni3Fe nanostructures, Cerium, Alkaline electrolyte Bull. Chem. Soc. Ethiop. 2020, 34(2), 353-363 DOI: https://dx.doi.org/10.4314/bcse.v34i2.12

Download Full-text

Investigation on adsorption capacity of TiO2-P25 nanoparticles in the removal of a mono-azo dye from aqueous solution: A comprehensive isotherm analysis

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq120610105b ◽

2014 ◽

Vol 20 (1) ◽

pp. 97-107 ◽

Cited By ~ 26

Author(s):

Mohammad Behnajady ◽

Shahrzad Yavari ◽

Nasser Modirshahla

Keyword(s):

Aqueous Solution ◽

Crystallite Size ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Correlation Coefficients ◽

Average Crystallite Size ◽

Isotherm Models ◽

Equilibrium Data ◽

Pseudo Second Order

In this work TiO2-P25 nanoparticles with high surface area have been used as adsorbent for the removal of C.I Acid Red 27 (AR27), as an organic contaminant from aqueous solution. Characteristics of phases and crystallite size of TiO2-P25 nanoparticles were achieved from XRD and the surface area and pore size distribution were obtained from BET and BJH techniques. TiO2-P25 nanoparticles with almost 80% anatase and 20% rutile phases, the average crystallite size of 18 nm, have specific surface area of 56.82 m2 g-1. The effect of various parameters like initial AR27 concentration, pH, contact time and adsorbent dosage has been carried out in order to find desired adsorption conditions. The desired pH for adsorption of AR27 onto TiO2-P25 nanoparticles was 3. The equilibrium data were analyzed with various 2-, 3- and 4-parameter isotherm models. Equilibrium data fitted very well by the 4-parameter Fritz-Schluender model. Results of adsorption kinetics study indicated that the pseudo-second order kinetics provided the best fit with correlation coefficients close to unity.

Download Full-text

Characterization of Residual Biomasses and Its Application for the Removal of Lead Ions from Aqueous Solution

Applied Sciences ◽

10.3390/app9214486 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4486 ◽

Cited By ~ 3

Author(s):

Candelaria Tejada-Tovar ◽

Angel Darío Gonzalez-Delgado ◽

Angel Villabona-Ortiz

Keyword(s):

Aqueous Solution ◽

Adsorption Process ◽

High Surface ◽

High Surface Area ◽

Freundlich Isotherm ◽

Mesoporous Structure ◽

Isotherm Models ◽

Solution Ph ◽

Batch Mode ◽

Suitable Alternative

The removal of water pollutants has been widely addressed for the conservation of the environment, and novel materials are being developed as adsorbent to address this issue. In this work, different residual biomasses were employed to prepare biosorbents applied to lead (Pb(II)) ion uptake. The choice of cassava peels (CP), banana peels (BP), yam peels (YP), and oil palm bagasse (OPB) was made due to the availability of such biomasses in the Department of Bolivar (Colombia), derived from agro-industrial activities. The materials were characterized by ultimate and proximate analysis, Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller analysis (BET), Scanning Electron Microscopy (SEM), and Energy Dispersive X-Ray Spectroscopy (EDS) in order to determine the physicochemical properties of bioadsorbents. The adsorption tests were carried out in batch mode, keeping the initial metal concentration at 100 ppm, temperature at 30 °C, particle size at 1 mm, and solution pH at 6. The experimental results were adjusted to kinetic and isotherm models to determine the adsorption mechanism. The remaining concentration of Pb(II) in solution was measured by atomic absorption at 217 nm. The functional groups identified in FTIR spectra are characteristic of lignocellulosic materials. A high surface area was found for all biomaterials with the exception of yam peels. A low pore volume and size, related to the mesoporous structure of these materials, make these bioadsorbents a suitable alternative for liquid phase adsorption, since they facilitate the diffusion of Pb(II) ions onto the adsorbent structure. Both FTIR and EDS techniques confirmed ion precipitation onto adsorbent materials after the adsorption process. The adsorption tests reported efficiency values above 80% for YP, BP, and CP, indicating a good uptake of Pb(II) ions from aqueous solution. The results reported that Freundlich isotherm and pseudo-second order best fit experimental data, suggesting that the adsorption process is governed by chemical reactions and multilayer uptake. The future prospective of this work lies in the identification of alternatives to reuse Pb(II)-contaminated biomasses after heavy metal adsorption, such as material immobilization.

Download Full-text

Large-scale and facile synthesis of a porous high-entropy alloy CrMnFeCoNi as an efficient catalyst

Journal of Materials Chemistry A ◽

10.1039/d0ta04940a ◽

2020 ◽

Vol 8 (35) ◽

pp. 18318-18326 ◽

Cited By ~ 1

Author(s):

Hailong Peng ◽

Yangcenzi Xie ◽

Zicheng Xie ◽

Yunfeng Wu ◽

Wenkun Zhu ◽

...

Keyword(s):

Catalytic Activity ◽

Surface Area ◽

Large Scale ◽

High Surface ◽

High Surface Area ◽

Catalytic Performance ◽

High Entropy Alloy ◽

Facile Synthesis ◽

Efficient Catalyst ◽

High Entropy

Porous high entropy alloy CrMnFeCoNi exhibited remarkable catalytic activity and stability toward p-nitrophenol hydrogenation. The enhanced catalytic performance not only resulted from the high surface area, but also from exposed high-index facets with terraces.

Download Full-text