scholarly journals Removal of an Ethoxylated Alkylphenol by Adsorption on Zeolites and Photocatalysis with TiO2/Ag

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 889 ◽  
Author(s):  
Claudia Aguilar Ucán ◽  
Mohamed Abatal ◽  
Carlos Montalvo Romero ◽  
Francisco Anguebes Franseschi ◽  
Miguel Angel Ramirez Elias ◽  
...  
Keyword(s):  
Diffuse Reflectance ◽  
Adsorption Process ◽  
Nano Particles ◽  
Natural State ◽  
Photocatalytic Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Removal Capacity ◽  
Pseudo Second Order ◽  
Degussa P25

Two advanced removal methods (adsorption and photocatalysis) were compared for the elimination of an ethoxylated alkylphenol (nonylphenol polyethylene glycol, NPEG). For the adsorption process, zeolites were used in their natural state, and the process was characterized by DRX (X-ray diffraction) and SEM–EDS (Scanning electron microscopy). The analysis of the results of the adsorption kinetics was carried out using different isotherms to interpret the removal capacity of zeolites. The Temkin kinetic model better predicted the experimental data and was satisfactorily adjusted to models of pseudo-second order (PSO). On the other hand, for photocatalysis, nano-particles of Ag (silver) were deposited on titanium oxide (TiO2) Degussa-P25 by photo-deposition, and the catalyst was characterized by diffuse reflectance and SEM–EDS. The data obtained using the two removal techniques were analyzed by UV–Vis (ultraviolet-visible spectrophotometry) and total organic carbon (TOC). The kinetic data were compared. The photocatalytic process showed the highest efficiency in the removal of NPEG, corresponding to >80%, while the efficiency of the adsorption process was <60%. This was attributed to the recalcitrant and surfactant nature of NPEG.

scholarly journals Synthesis Fe3O4/Talc nanocomposite by coprecipition-ultrasonication method and advances in hexavalent chromium removal from aqueous solution

2020 ◽  
Vol 38 (9-10) ◽  
pp. 483-501
Author(s):  
Nguyen Thi Huong ◽  
Nguyen Ngoc Son ◽  
Vo Hoang Phuong ◽  
Cong Tien Dung ◽  
Pham Thi Mai Huong ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Process ◽  
Low Cost ◽  
Batch Experiments ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Langmuir And Freundlich Equations

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.

scholarly journals Removal of Cesium and Strontium From Radioactive Wastewater by Prussian Blue Nanorods

2022 ◽  
Author(s):  
Chuqing Yao ◽  
Yaodong Dai ◽  
Shuquan Chang ◽  
Haiqian Zhang
Keyword(s):  
Prussian Blue ◽  
Photoelectron Spectroscopy ◽  
Adsorption Process ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Radioactive Wastewater ◽  
Pseudo Second Order ◽  
Co Precipitation ◽  
Solvothermal Methods

Abstract In this work, novel Prussian blue tetragonal nanorods were prepared by template-free solvothermal methods for removal of radionuclide Cs and Sr. It was worth that Prussian blue nanorods exhibited the better adsorption performance than co-precipitation PB or Prussian blue analogue composites. Thermodynamic analysis implied that adsorption process was spontaneous and endothermic which was described well with Langmuir isotherm and pseudo-second-order equation, the maximum adsorption capacity of PB nanorod was estimated to be 194.26 mg g-1 and 256.62 mg g-1 for Cs+ and Sr2+. The adsorption mechanism of Cs+ and Sr2+ was studied by X-ray photoelectron spectroscopy, X-ray diffraction and 57Fe Mössbaure spectroscopy, the results revealed that Cs+ entered in PB crystal to generate a new phase, the most of Sr2+ was trapped in internal crystal and the other exchanged Fe2+. Furthermore, the effect of co-existing ions and pH for PB adsorption process were also investigated. The results suggest that PB nanorods were outstanding candidate for removal of Cs+ and Sr2+ from radioactive wastewater.

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

2017 ◽  
Vol 8 (3) ◽  
pp. 350-359 ◽  
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.

scholarly journals Structuring of ZnTiO3/TiO2 Adsorbents for the Removal of Methylene Blue, Using Zeolite Precursor Clays as Natural Additives

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 898
Author(s):  
Ximena Jaramillo-Fierro ◽  
Silvia González ◽  
Fernando Montesdeoca-Mendoza ◽  
Francesc Medina
Keyword(s):  
Methylene Blue ◽  
Adsorption Process ◽  
Sol Gel ◽  
Area Measurement ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Surface Area Measurement ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order

Adsorption is an effective method of removing harmful pollutants from air and water. In the present study, zeolites prepared by sol-gel method from two Ecuadorian clays were combined with precursor clays and the ZnTiO3/TiO2 semiconductor for adsorbing methylene blue (MB) as a water contaminant. The synthesized compounds were characterized using powder X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive X-ray, and surface area measurement. These compounds were combined to form cylindrical extrudates of 0.2 cm (diameter) and 1.0 cm (length). The adsorption characteristics of the composites were measured using batch sorption studies as a function of pH, initial concentration, and contact time. The pseudo-second-order model and the Langmuir isotherm model were better suited to the adsorption process. The equilibrium state was achieved around 180 min of adsorption, and a pH of 7 was established as the optimal operating condition. The maximum adsorption values of the dye were obtained with the composites derived from G-Clay, whose average adsorption capacity was 46.36 mg g−1, in contrast with composites derived from R-Clay, whose average adsorption value was 36.24 mg g−1. The results reflect that synthesized composites could be used potentially for the removal of cationic dye from wastewater.

scholarly journals Synthesis, Characterization, and Evaluation of Degussa P25/Chitosan Composites for the Photocatalytic Removal of Sertraline and Acid Red 18 from Water

2021 ◽  
Author(s):  
M. Rejek ◽  
J. Grzechulska-Damszel ◽  
B. Schmidt
Keyword(s):  
Diffuse Reflectance ◽  
Preparation Method ◽  
Crosslinking Agent ◽  
Major Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chitosan Matrix ◽  
Organic Impurities ◽  
Photocatalytic Removal ◽  
Degussa P25

Abstract Degussa P25 titanium dioxide/chitosan composites (P25/CS) were prepared using three different methods and two different chitosan materials. The obtained materials were characterized by diffuse reflectance UV–Vis, Fourier-transform infrared spectroscopies, X-ray diffraction, and scanning electron microscopy. It was observed for all prepared materials that the chitosan surface is homogeneously covered by Degussa P25, the particles are evenly dispersed on the whole chitosan matrix and do not form agglomerates. The performance of P25/CS composites were tested in water treatment by the photocatalytic reaction of sertraline and Acid Red 18. The obtained results show that the application of prepared composites is effective in the reaction of decomposition of model organic impurities in water. Moreover, chitosan presence in the photocatalytic materials considerably facilitates the separation of catalyst from the reaction mixture, which is a great advantage compared to pure Degussa P25. The preparation method did not show a major effect on the photocatalytic activity. The method using glutaraldehyde as the crosslinking agent is the simplest one; thus, it is recommended for Degussa P25/chitosan nanocomposites preparation. These nanocomposites can be successfully applied in water purification by photocatalytic degradation of organic pollutants. Graphic Abstract

Research on Lead (II) Adsorption Mechanism from Aqueous Solution by Calcium Carbonate Modified Diatomite Absorbent

2018 ◽  
Vol 921 ◽  
pp. 21-28 ◽  
Author(s):  
Li Li Ma ◽  
Qing Lin Xie ◽  
Nan Chun Chen ◽  
Hui Xu ◽  
Hai Miao Zhou ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Calcium Carbonate ◽  
Adsorption Isotherms ◽  
Adsorption Mechanism ◽  
Adsorption Process ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pseudo Second Order ◽  
Modified Diatomite

In this study, calcium carbonate was used to coat and link the surface of diatomite for the formation of a novel modified adsorbent (referred to as Ca–diatomite). Various analytical techniques were used to characterize structure and mechanisms of modification and adsorption process, like Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). Results showed that that Calcium carbonate had been successful grafted onto the surface of diatomite after modification, and Calcium carbonate modification improved the adsorption performance of diatomite for the removal of lead (II) ions from aqueous solution. Ca–diatomite adsorption isotherms and adsorption kinetics were also been studied. The adsorption isotherms and the kinetic data were best fitted with the Langmuir model and pseudo-second-order kinetics, respectively.

scholarly journals Removal and Comparative Adsorption of Anionic Dye on Various MgAl synthetic Clay

2021 ◽  
Vol 11 (6) ◽  
pp. 14986-14997
Keyword(s):  
Congo Red ◽  
Adsorption Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Batch System ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Red Dye ◽  
Synthetic Clay

In this study, the adsorption of Congo red dye in an aqueous solution on two synthetic clay adsorbents, MgAl-LDH (2:1) and MgAl-LDH (3:1), was investigated using batch system experiments. The adsorbents' characterization was carried out by various techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy FT-IR. The conditions applied in the adsorption experiments including the mass of adsorbent, initial concentration, contact time, pH, and temperature. The kinetic data were modeled by pseudo-first-order and pseudo-second-order. Langmuir and Freundlich's models analyzed the adsorption isotherms of Congo red on the two adsorbents. It was found that the adsorption process could be described by Langmuir isotherm. The maximum amount of adsorption is 285.71 and 166.66 mg/g for MgAl-LDH (2:1) and MgAl-LDH (3:1), respectively. Thermodynamic parameters such as enthalpy ∆H°, enthalpy ∆S°, and free enthalpy ∆G° were also evaluated to predict the nature of adsorption.

scholarly journals A new Fe3O4/CuO/AC Nanocomposite for Imidacloprid Removal: Characterization, Optimization, and Adsorption Modeling

2021 ◽  
Author(s):  
Amrollah Parsaie ◽  
Nadereh Rahbar ◽  
Mohamadreza Baezat
Keyword(s):  
Adsorption Process ◽  
Freundlich Isotherm ◽  
Influential Factors ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Pesticide Concentration ◽  
X Ray ◽  
Adsorption Modeling ◽  
Pseudo Second Order ◽  
First Time

Abstract A new magnetic adsorbent (Fe3O4/CuO/AC) composed of magnetite (Fe3O4) and copper oxide (CuO) nanoparticles Impregnated with activated carbon (AC) has been fabricated and used for the first time to remove imidacloprid (IMCP) insecticide from the aqueous solutions. This composite was characterized using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction, energy dispersive x-ray diffraction, and vibrating sample magnetometer. The main influential factors such as the solution pH, the adsorbent amount, temperature, agitating time, and initial pesticide concentration were also tested to evaluate the optimized condition. Based on the results obtained from isotherm and kinetic modeling, the adsorption mechanism of IMCP on Fe3O4/CuO/AC is a combination of physisorption and chemisorption phenomena. The experimental data fitted best to the Freundlich isotherm model revealing the presence of heterogeneous sites for IMCP adsorption. Besides, the kinetics results revealed that the adsorption process well fitted with pseudo-second-order model, implying that the chemisorption was determining step in adsorption process. Thermodynamic results showed the spontaneous and exothermic nature of the adsorption process. Under optimal conditions (pH 7; contact time, 10 min; initial pesticide concentration, 10 mg L-1), IMCP removal efficiency was 99.6%, indicating the excellent ability of Fe3O4/CuO/AC nanocomposite for the adsorption of this pesticide from water solutions.

scholarly journals PENGOLAHAN LIMBAH Cr(VI) DAN FENOL DENGAN FOTOKATALIS SERBUK TiO2 DAN CuO/TiO2

REAKTOR ◽  
2007 ◽  
Vol 11 (2) ◽  
pp. 78 ◽  
Author(s):  
Slamet Slamet ◽  
R. Arbianti ◽  
E. Marliana
Keyword(s):  
Band Gap ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Black Light ◽  
Degussa P25

Studi tentang pengolahan limbah Cr(VI) dan fenol secara fotokatalisis telah dilakukan dengan fotokatalis TiO2 dan CuO/TiO2. Katalis CuO/TiO2 dipreparasi dengan cara impregnasi terhadap TiO2 Degussa P25 menggunakan larutan garam tembaga yang berasal dari berbagai jenis prekursor. Komposisi Cu dalam katalis divariaskani dari 0,2% hingga 5%. Fotokatalis tersebut kemudian dikarakterisasi DRS (Diffuse Reflectance Spectroscopy) dan XRD (X-Ray Diffraction). Aktivitas fotokatalis diuji dengan menggunakan sistem reaktor slurry yang bekerja secara batch dan dilengkapi dengan 6 lampu UV black light selama 5 jam, kemudian hasilnya dianalisis dengan UV-VIS Spectrophotometer. Hasil karakterisasi DRS menunjukan bahwa penambahan CuO dari 1% hingga 5% ke dalam TiO2 dapat meningkatkan pita absorbansi katalis dari 398 hingga 413 nm dan menurunkan band gap dari 3,2 hingga 2,58 eV. Hasil karakterisasi XRD menunjukan adanya struktur kristal anatase dan rutil dalam katalis TiO2 dan CuO/TiO2, sementara struktur kristal CuO muncul pada katalis CuO/TiO2 yang dipreparasi dengan prekursor Cu-Asetat dan Cu-Nitrat. Fotokatalis 0,2% CuO/TiO2 dari prekursor Cu-Asetat memiliki aktivitas optimal yang mereduksi Cr(VI) 99,67% dan mendegradasi fenol 97,16%. Sementara jika kedua limbah tersebut diolah secara simultan, katalis TiO2 Degussa P25 memiliki aktivitas yang paling tinggi dengan meningkatkan konversi reduksi Cr(VI) menjadi 100% dan menurunkan konversi degradasi fenol menjadi 93,81% dengan waktu reaksi 5 jam.

scholarly journals Removal And Regeneration of As(V) In Aqueous Solutions By Adsorption On Calcined Fluorapatite: Kinetics And Thermodynamic Parameters.

2021 ◽  
Author(s):  
Rachid EL Kaim Billah ◽  
Savaş Kaya ◽  
Selçuk Şimşek ◽  
El Mahdi Halim ◽  
Mahfoud Agunaou ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Regression Coefficient ◽  
Mass Effect ◽  
Significant Loss ◽  
X Ray Diffraction ◽  
X Ray ◽  
Langmuir Adsorption ◽  
Adsorption Data ◽  
Pseudo Second Order ◽  
Effect Time

Abstract In this work, Fluorapatite has been prepared and successfully applied for the removal of As (VI). The materials prepared have been characterized using X-ray diffraction (XRD), infrared transform transform spectroscopy. Fourier (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Thermogravimetric analysis (TGA) and zero load point pH (pHPZC) were also considered as part of these characterizations. In this work, several parameters affecting the adsorption process were studied, such as: the mass effect, time, pH, and the initial concentration effect. The value of the regression coefficient showed that the data The experimental results corresponded best to the pseudo-second order (PSO) model, while the Langmuir adsorption isotherms best described the equilibrium adsorption data with the highest qm of 43.10 mg / g. Finally, FapC has been successfully reused for more than 5 cycles without significant loss of its sorption capacity.

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