Efficient Removal of Cd(II) Using SiO2-Mg(OH)2 Nanocomposites Derived from Sepiolite

The pollution of Cadmium (Cd) species in natural water has attracted more and more attention due to its high cumulative toxicity. In the search for improved removal of cadmium from contaminated water, we characterized uptake on a recently identified nanomaterial (SiO2-Mg(OH)2) obtained by subjecting sepiolite to acid-base modification. The structural characteristics of SiO2-Mg(OH)2 were analyzed by means of SEM-EDS, Fourier Transform Infra-Red Spectroscopy (FTIR) and Powder X-ray Diffraction (PXRD). Static adsorption experiments were carried out to evaluate the effect of contact time, temperature, amount of adsorbent, and pH-value on the adsorption of Cd(II) by SiO2-Mg(OH)2. The results show that the pore structure of SiO2-Mg(OH)2 is well developed, with specific surface area, pore size and pore volume increased by 60.09%, 16.76%, and 43.59%, respectively, compared to natural sepiolite. After modification, the sepiolite substrate adsorbs Cd(II) following pseudo-second-order kinetics and a Langmuir surface adsorption model, suggesting both chemical and physical adsorption. At 298 K, the maximum saturated adsorption capacity fitted by Sips model of SiO2-Mg(OH)2 regarding Cd(II) is 121.23 mg/g. The results show that SiO2-Mg(OH)2 nanocomposite has efficient adsorption performance, which is expected to be a remediation agent for heavy metal cadmium polluted wastewater.

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Adsorption characteristics of ciprofloxacin on the schorl: kinetics, thermodynamics, effect of metal ion and mechanisms

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2017.143 ◽

2017 ◽

Vol 8 (3) ◽

pp. 350-359 ◽

Cited By ~ 11

Author(s):

Danyang Yin ◽

Zhengwen Xu ◽

Jing Shi ◽

Lili Shen ◽

Zexiang He

Keyword(s):

Photoelectron Spectroscopy ◽

Metal Ion ◽

Adsorption Process ◽

Ph Value ◽

Physical Adsorption ◽

Order Kinetic ◽

X Ray Diffraction ◽

X Ray ◽

Order Kinetic Model ◽

Pseudo Second Order

Abstract In this study, schorl was used as an effective adsorbent for ciprofloxacin removal from wastewater. The adsorption performance, mechanism and effect of metal ion on sorption were investigated. Adsorption capacity reached a maximum (8.49 mg/g) when the pH value was 5.5. The pseudo-second-order kinetic model and Freundlich model could better describe the experimental data. The negative ΔH (–22.96 KJ/mol) value showed that the adsorption process was exothermic. The results also indicated physical adsorption existed on the adsorption process, which was in agreement with the analysis of X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy. The desorption rate could reach 94%, which suggested that schorl had a good desorption and regeneration performance. Coexisting ions, such as Cu2+ and Al3+, could obviously inhibit adsorption, and the inhibition from Al3+ was significantly higher than that from Cu2+. However, the additional Zn2+ could slightly promote the adsorption.

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Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽

10.3390/ma14102518 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2518

Author(s):

Dorota Kołodyńska ◽

Yongming Ju ◽

Małgorzata Franus ◽

Wojciech Franus

Keyword(s):

Experimental Data ◽

Aspartic Acid ◽

Ph Value ◽

Complexing Agents ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Modified Zeolite ◽

X Ray ◽

Slow Release Fertilizers ◽

Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

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Kinetics of Cr(VI) adsorption from aqueous medium onto bentonite

GLASNIK HEMIČARA TEHNOLOGA I EKOLOGA REPUBLIKE SRPSKE ◽

10.7251/ghte1915009p ◽

2020 ◽

Vol 11 (15) ◽

Author(s):

Rada Petrović

Keyword(s):

Heavy Metals ◽

Aqueous Medium ◽

Ph Value ◽

Second Order ◽

Human Beings ◽

Adsorption Model ◽

Solution Ph ◽

Initial Ph ◽

Isotherm Adsorption ◽

Pseudo Second Order

Because of its abundance and toxicity, heavy metals have become a seriousenvironmental problem. The presence of heavy metals, such as Cr(VI), in thewatercourses leads to numerous health problems in humans and animals. Cr(VI) ishighly toxic, even in low concentrations. Because of its carcinogenic, mutagenic andteratogenic effects on human beings, Cr(VI) is considered one of the most criticalpollutants. Due to this, it is necessary to remove Cr(VI) from wastewater prior to itsdischarge into the recipient.This paper studied the possibility for application of bentonite as an adsorbent forCr(VI) from aqueous medium. The characterization of bentonite was determined withchemical composition, specific surface, XRD method and FTIR. Optimal parameterssuch as pH of solution, adsorbent weight, time of adsorption and temperaturewere examined. Values of those parameters were: initial pH value of solution pH=2,adsorbent weight 2 g, time of adsorption 60 min, temperature 308 K. Experimentaldata were obtained by Freundlich and Langmuir isotherm adsorption models as wellas pseudo-first and pseudo-second order kinetics. Results were best described withFreundlich isotherm adsorption model and pseudo-second order kinetics.

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Adsorption Behavior of Cationic Dye on Bentonite Functionalized With 3-aminopropyltriethoxysilane

10.21203/rs.3.rs-826750/v1 ◽

2021 ◽

Author(s):

MAZOURI BELHADRI ◽

Adel Mokhtar ◽

Abdelkader Bengueddach Bengueddach ◽

mohamed sassi

Keyword(s):

Bentonite Clay ◽

Exchange Capacity ◽

Blue Dye ◽

Adsorption Model ◽

X Ray Diffraction ◽

Adsorption Parameters ◽

Modified Clay ◽

Pseudo Second Order ◽

Cationic Exchange ◽

Hydrolysis Of

Abstract The current study focused on the modification of Algerian bentonite clay (Bent) with the product of hydrolysis of 3-aminopropyltriethoxysilane (APTES) using the intercalation process. The modified clay (Bent-APTES) was investigated as an adsorbent solid for methylene blue dye (MB) removal from wastewater.The Bent-APTES was characterized by X-ray diffraction (XRD), chemical analyses, Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The cationic exchange capacity was also determined. Several adsorption parameters were evaluated on the adsorption performance. The results showed that the equilibrium adsorption data was found to fit better to the Langmuir adsorption model, and the adsorption capacity for the removal of MB on Bent-APTES was 217.39 mg g-1. The kinetic process of adsorption could be described by the pseudo-second order model. Consequently, the modified clay could be served as an efficient adsorbent for cationic dyes in wastewater treatment.

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Adsorption Properties of Comb-Shaped Polycarboxylate Dispersant onto Different Crystal Pyraclostrobin Particle Surfaces

Molecules ◽

10.3390/molecules25235637 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5637

Author(s):

Liying Wang ◽

Chong Gao ◽

Jianguo Feng ◽

Yong Xu ◽

Danqi Li ◽

...

Keyword(s):

Physical Adsorption ◽

Order Kinetic ◽

Adsorption Model ◽

Adsorption Models ◽

Crystal Forms ◽

Adsorption Processes ◽

Different Temperatures ◽

Pseudo Second Order ◽

The Stability ◽

Crystalline Forms

The stability of the suspension system of the two crystal forms of pyraclostrobin is evaluated using multiple light technology, and the adsorption performance of polycarboxylate dispersant on the surface of two different crystalline pyraclostrobin particles is compared in combination with XRD, FTIR, XPS, and SEM from the microscopic view. The adsorption kinetics and thermodynamics studies of 2700 on the surfaces of different crystalline forms of pyraclostrobin particles show that the adsorption process of 2700 on the surfaces of pyraclostrobin crystal forms II and IV conform to pseudo-second-order kinetic adsorption model. The Ea values for crystal forms II and IV are 12.93 and 14.39 kJ∙mol−1, respectively, which indicates that both adsorption processes are physical adsorption. The adsorption models of 2700 on the surfaces of pyraclostrobin crystal forms II and IV are in accordance with Langmuir adsorption isotherms. The ∆Gad values of crystal forms II and IV are negative and the ∆Sad values are positive at different temperatures. Therefore, the adsorption processes are spontaneous and accompanied by entropy increase. The results of this study provide an important theoretical basis for the selection of polycarboxylate dispersants in the suspension of pyraclostrobin. This study also provides a reference for the research of polycrystalline pesticide suspension concentrate.

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Removal of Tetracycline in Sewage and Dairy Products with High-Stable MOF

Molecules ◽

10.3390/molecules25061312 ◽

2020 ◽

Vol 25 (6) ◽

pp. 1312 ◽

Cited By ~ 1

Author(s):

Kan Li ◽

Jing-jing Li ◽

Ni Zhao ◽

Ying Ma ◽

Bin Di

Keyword(s):

Dairy Products ◽

Physical Adsorption ◽

Metal Organic Framework ◽

High Porosity ◽

Adsorption Model ◽

Initial Ph ◽

Metal Organic ◽

Pseudo Second Order ◽

The Stability ◽

Best Fit

Serious environmental and human health problems caused by the abuse of antibiotics have attracted worldwide concern. Recently, metal–organic frameworks (MOFs) with high porosity have drawn wide attention for their effects in the adsorption and removal of pollutants from complex matrices. Herein, a high-stable metal organic framework (MOF), i.e., ((ZnCl2)3(L)2·DMF)n, where L=1,3,5-tris((pyridin-4-ylthio)methyl)benzene), MOF 1, was applied to adsorb and remove tetracycline from sewage and dairy products. The results showed that MOF 1 exhibited a strong performance in the adsorption of tetracycline. The effects of initial pH values, adsorbent dose, contact time and ionic strength of the adsorption performance of MOF 1 were investigated. The adsorption kinetics best fit the pseudo-second order model, and the adsorption isotherms matched the Langmuir adsorption model well. It was indicated that both chemical adsorption and physical adsorption play an important role in the adsorption process, and the adsorption of tetracycline was homogeneous and occurred on a monolayer on the surface of MOF 1. Additionally, the stability of MOF 1 and the details of the adsorption mechanism were also investigated. Thus, this study provides a new candidate for the application of MOFs-based adsorbents in the removal of antibiotics from sewage and dairy products.

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Cerium Oxide/Polypyrrole Nanocomposite as the Matrix for Cholesterol Biosensor

Advances in Polymer Technology ◽

10.1155/2021/6627645 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Ta Thi Nhat Anh ◽

Vu Van Thu ◽

Hai-Son Dang ◽

Vuong-Hung Pham ◽

Phuong Dinh Tam

Keyword(s):

Cerium Oxide ◽

Ph Value ◽

Physical Adsorption ◽

Cholesterol Oxidase ◽

Diffraction Field ◽

Optimal Parameters ◽

X Ray Diffraction ◽

X Ray ◽

The Matrix ◽

Cholesterol Biosensor

A nanocomposite comprising cerium oxide nanoparticles (CeO2 NPs) and polypyrrole (PPy) was fabricated onto a microelectrode for cholesterol sensing application. The cholesterol oxidase (ChOx) was immobilized on the CeO2 NPs/PPy/electrode by the physical adsorption route. The structure and morphology of the CeO2 NPs/PPy nanocomposite were characterized by X-ray diffraction, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy. Results showed that the ChOx/CeO2 NPs/PPy/electrode was linearly related with cholesterol in the range of 50 to 500 mg/dL. The sensitivity of ChOx/CeO2 NPs/PPy/electrode was 5.7 × 10 − 6 mA/mg⋅dL−1. The optimal parameters, including pH value and temperature, and selectivity, storage stability, and reproducibility of ChOx/CeO2 NPs/PPy/electrode were investigated.

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Characterization of biochar prepared from slow pyrolysis of Jordanian olive oil processing solid waste and adsorption efficiency of Hg2+ ions in aqueous solutions

Water Science & Technology ◽

10.2166/wst.2016.378 ◽

2016 ◽

Vol 74 (8) ◽

pp. 1899-1910 ◽

Cited By ~ 14

Author(s):

Ali El Hanandeh ◽

Rund A. Abu-Zurayk ◽

Imad Hamadneh ◽

Ammar H. Al-Dujaili

Keyword(s):

Aqueous Solutions ◽

Olive Oil ◽

Solid Waste ◽

Ph Value ◽

Order Kinetic ◽

X Ray Diffraction ◽

Slow Pyrolysis ◽

Oil Processing ◽

Order Kinetic Model ◽

Pseudo Second Order

Solid waste from Jordanian olive oil processing (OOSW) was used to prepare biochar samples by slow pyrolysis at terminal temperatures of 350, 450, 550 and 630 °C; henceforth known as BC-350, BC-450, BC-550 and BC-630, respectively. These samples were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction, ash content, moisture content and surface area. The ability of the biochar to remove Hg2+ ions from aqueous solutions was investigated in laboratory scale batch experiments. The kinetics, effect of pH and temperature were studied. The optimum pH value for Hg2+ adsorption was 5. Dubinin-Radushkevich (D-R) isotherm model was the best fit for the experimental results. Based on the D-R model, the maximum adsorption capacities at 25 °C were 84.93, 94.48, 96.11 and 104.59 mg.g−1, for BC-350, BC-450, BC-550 and BC-630, respectively. The pseudo-second-order kinetic model was a good fit for the experimental data. The calculated change in free energy ΔG and enthalpy ΔH indicated that the adsorption process was spontaneous and exothermic in nature. The positive value of ΔS showed increased randomness of the solid/solution interface during the adsorption. The results indicated that biochar derived from OOSW can be a good adsorbent for treatment of water contaminated with Hg2+.

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Adsorption of Cu(II) on natural and treated clays

Water Quality Research Journal ◽

10.2166/wqrjc.2015.051 ◽

2015 ◽

Vol 51 (1) ◽

pp. 26-32 ◽

Cited By ~ 2

Author(s):

Mustapha Djebbar ◽

Fatiha Djafri

Keyword(s):

Adsorption Capacity ◽

Ph Value ◽

Copper Ions ◽

Low Cost ◽

Scale Up ◽

Adsorption Model ◽

X Ray Diffraction ◽

Monolayer Adsorption ◽

Equilibrium Data

We have studied the pH and the temperature effects on copper ions' adsorption on natural and treated clays from Algeria. The clay was also treated to improve the adsorption capacity. X-ray diffraction identified montmorillonite and kaolinite as major clay minerals. The Langmuir adsorption model was used for the mathematical description of the adsorption equilibrium and the equilibrium data adhered very well to this model. The treated and natural clay had a monolayer adsorption capacity equal to 15.40 and 12.22 mg/g, respectively, at pH value of 6.5 and temperature 20 °C, the adsorption isotherms could be fitted with Langmuir isotherms, and the coefficients indicated favorable adsorption of Cu(II) on the clays. Determination of the thermodynamic parameters, H, S, and G showed that the adsorption process was spontaneous and exothermic accompanied by a decrease in entropy and Gibbs energy. Results of this study will be useful for future scale-up for using this material as a low-cost adsorbent for the removal of Cu(II) from wastewater.

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Adsorption of anionic dye onto magnetic Fe3O4/CeO2 nanocomposite: Equilibrium, kinetics, and thermodynamics

Adsorption Science & Technology ◽

10.1177/0263617418819164 ◽

2019 ◽

Vol 37 (3-4) ◽

pp. 185-204 ◽

Cited By ~ 7

Author(s):

Shaomin Gao ◽

Wenwen Zhang ◽

Zhaohui An ◽

Shulin Kong ◽

Donghui Chen

Keyword(s):

Electron Microscopy ◽

Energy Dispersive Spectrometer ◽

Precipitation Method ◽

Maximum Adsorption Capacity ◽

Adsorption Model ◽

X Ray Diffraction ◽

Anionic Dye ◽

Transmission Electron ◽

Initial Ph ◽

Pseudo Second Order

In this study, a magnetically separable Fe3O4/CeO2 (Fe/Ce) nanocomposite is synthesized by sol-precipitation method and characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy dispersive spectrometer , vibrating sample magnetometer, atomic absorption spectrometer, and zeta potential measurements. The Fe/Ce is used as sorbent to adsorb anionic dye of Acid Black 210 (AB210) from aqueous solutions, and the maximum adsorption capacity is about 90.50 mg/g, which is six times higher than that of the commercial CeO2. Dependence of absorption performance on essential factors, such as initial dye concentration, temperature and initial pH, are experimentally examined. The result shows that the adsorption kinetic of Fe/Ce follows pseudo-second-order model and the adsorption isotherm is well described by the Langmuir adsorption model. Furthermore, the thermodynamic analysis indicates that the adsorption of Fe/Ce for AB210 is spontaneous and endothermic.

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