scholarly journals Hybrid Materials Based on Silica Matrices Impregnated with Pt-Porphyrin or PtNPs Destined for CO2 Gas Detection or for Wastewaters Color Removal

2020 ◽  
Vol 21 (12) ◽  
pp. 4262 ◽  
Author(s):  
Diana Anghel ◽  
Anca Lascu ◽  
Camelia Epuran ◽  
Ion Fratilescu ◽  
Catalin Ianasi ◽  
...  
Keyword(s):  
Hybrid Materials ◽  
Sol Gel ◽  
Dye Adsorption ◽  
Kinetic Studies ◽  
Base Catalysis ◽  
Morphological Properties ◽  
Order Kinetic ◽  
Co2 Gas ◽  
Bet Analysis ◽  
Silica Matrices

Multifunctional hybrid materials with applications in gas sensing or dye removal from wastewaters were obtained by incorporation into silica matrices of either Pt(II)-5,10,15,20-tetra-(4-allyloxy-phenyl)-porphyrin (PtTAOPP) or platinum nanoparticles (PtNPs) alone or accompanied by 5,10,15,20-tetra-(4-allyloxy-phenyl)-porphyrin (TAOPP). The tetraethylorthosilicate (TEOS)-based silica matrices were obtained by using the sol-gel method performed in two step acid-base catalysis. Optical, structural and morphological properties of the hybrid materials were determined and compared by UV-vis, fluorescence and FT-IR spectroscopy techniques, by atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM) and by Brunauer–Emmett–Teller (BET) analysis. PtTAOPP-silica hybrid was the most efficient material both for CO2 adsorption (0.025 mol/g) and for methylene blue adsorption (7.26 mg/g) from wastewaters. These results were expected due to both the ink-bottle mesopores having large necks that exist in this hybrid material and to the presence of the porphyrin moiety that facilitates chemical interactions with either CO2 gas or the dye molecule. Kinetic studies concerning the mechanism of dye adsorption demonstrated a second order kinetic model, thus it might be attributed to both physical and chemical processes.

scholarly journals Hybrid Silica Materials Applied for Fuchsine B Color Removal from Wastewaters

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 863
Author(s):  
Ion Fratilescu ◽  
Zoltán Dudás ◽  
Mihaela Birdeanu ◽  
Camelia Epuran ◽  
Diana Anghel ◽  
...  
Keyword(s):  
Hybrid Materials ◽  
Platinum Nanoparticles ◽  
Sol Gel ◽  
Base Catalysis ◽  
Color Removal ◽  
Force Microscopy ◽  
Atomic Force ◽  
Porphyrin Derivatives ◽  
Vis Spectroscopy ◽  
Silica Matrices

Hybrid materials, with applications in fuchsine B color removal from wastewaters, were obtained by in situ incorporation of platinum nanoparticles and/or Pt-porphyrin derivatives into silica matrices. The inorganic silica matrices were synthesized by the sol-gel method, conducted in acid-base catalysis in two steps and further characterized by Nitrogen porosimetry, Small Angle Neutron Scattering (SANS), Scanning electron microscopy, Atomic force microscopy and UV-vis spectroscopy. All of the investigated silica hybrid materials were 100% efficient in removing fuchsine B if concentrations were lower than 1 × 10−5 M. For higher concentrations, the silica matrices containing platinum, either modified with Pt-metalloporphyrin or with platinum nanoparticles (PtNPs), are the most efficient materials for fuchsine B adsorption from wastewaters. It can be concluded that the presence of the platinum facilitates chemical interactions with the dye molecule through its amine functional groups. An excellent performance of 197.28 mg fuchsine B/g adsorbent material, in good agreement with the best values mentioned in literature, was achieved by PtNPs-silica material, capable of removing the dye from solutions of 5 × 10−4 M, even in still conditions.

scholarly journals Tuning the Morphological Properties of Cellulose Aerogels: An Investigation of Salt-Mediated Preparation

2021 ◽  
Author(s):  
Prakash Parajuli ◽  
Sanjit Acharya ◽  
Julia Shamshina ◽  
Noureddine Abidi
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Sol Gel ◽  
Earth Metal ◽  
Morphological Properties ◽  
Cellulose Solution ◽  
Bet Analysis ◽  
Sol Gel Transition ◽  
Gel Transition

Abstract In this study, alkali and alkaline earth metal chlorides with different cationic radii (LiCl, NaCl, and KCl, MgCl2, and CaCl2) were used to gain insight into the behavior of cellulose solutions in the presence of salts. The specific focus of the study was evaluation of the effect of salts’ addition on the sol-gel transition of the cellulose solutions and on their ability to form monoliths, as well as evaluation of the morphology (e.g., specific surface area, pore characteristics, and microstructure) of aerocelluloses prepared from these solutions. The effect of the salt addition on the sol-gel transition of cellulose solutions was studied using rheology, and morphology of resultant aerogels was evaluated by Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, while the salt influence on the aerocelluloses’ crystalline structure and thermal stability was evaluated using powder X-Ray Diffraction (pXRD) and Thermogravimetric Analysis (TGA), respectively. The study revealed that the effect of salts’ addition was dependent on the component ions and their concentration. The addition of salts in the amount below certain concentration limit significantly improved the ability of the cellulose solutions to form monoliths and reduced the sol-gel transition time. Salts of lower cationic radii had a greater effect on gelation. However, excessive amount of salts resulted in the formation of fragile monoliths or no formation of gels at all. Analysis of surface morphology demonstrated that the addition of salts resulted in a significant increase in porosity and specific surface area, with salts of lower cationic radii leading to aerogels with much larger (~1.5 and 1.6-fold for LiCl and MgCl2, respectively) specific surface area compared to aerocelluloses prepared with no added salt. Thus, by adding the appropriate salt into the cellulose solution prior to gelation, the properties of aerocelluloses that control material’s performance (specific surface area, density, and porosity) could be tailored for a specific application.

scholarly journals Mg-Cr Layered Double Hydroxide Intercalated Oxalic Anion to Remove Cationic Dye Solutions: Rhodamine B and Methylene Blue

2020 ◽  
Vol 9 (2) ◽  
pp. 383-391
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Layered Double Hydroxide ◽  
Rhodamine B ◽  
Physical Adsorption ◽  
Dye Adsorption ◽  
Kinetic Studies ◽  
Economic Feasibility ◽  
Order Kinetic ◽  
Double Hydroxide

A MgCr-based layered double hydroxide (LDH) was synthesized by a coprecipitation method, followed by an intercalation process using an oxalic anion. The materials were characterized using X-ray diffraction analysis, FT-IR spectroscopy, and pH pzc measurement. The materials were then applied as adsorbents for removal of methylene blue (MB) and rhodamine B (RhB) from aqueous solution. Pristine Mg/Cr LDH exhibited RhB adsorption capacity of 32.154 mg g⁻1, whereas the use of intercalated Mg/Cr LDH caused an increase in the capacity (139.526 mg g⁻1). Kinetic studies indicated that the dye adsorption using both LDHs followed a pseudo-second-order kinetic model; the K2 values of pristine and modified Mg/Cr LDH for RhB and MB were 6.970, 0.001, 0.426, and 2.056 g mg⁻1 min⁻1, respectively. The thermodynamic study identified that the adsorption of both dyes onto the LDHs was a spontaneous process and can be classified as physical adsorption with adsorption energies of <40 kJ/mol. Moreover, the desorption and regeneration experiments indicated the high economic feasibility and reusability of the LDHs. By using HCl as the optimal solvent, the LDHs could desorb as much as 98% of the dye and could be used as adsorbents with high adsorption capacity over three cycles.

Parametric and adsorption kinetic studies of methylene blue removal from simulated textile water using durian (Durio zibethinus murray) skin

2015 ◽  
Vol 72 (6) ◽  
pp. 896-907 ◽  
Author(s):  
S. M. Anisuzzaman ◽  
Collin G. Joseph ◽  
D. Krishnaiah ◽  
A. Bono ◽  
L. C. Ooi
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Dye Adsorption ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Durio Zibethinus

In this study, durian (Durio zibethinus Murray) skin was examined for its ability to remove methylene blue (MB) dye from simulated textile wastewater. Adsorption equilibrium and kinetics of MB removal from aqueous solutions at different parametric conditions such as different initial concentrations (2–10 mg/L), biosorbent dosages (0.3–0.7 g) and pH solution (4–9) onto durian skin were studied using batch adsorption. The amount of MB adsorbed increased from 3.45 to 17.31 mg/g with the increase in initial concentration of MB dye; whereas biosorbent dosage increased from 1.08 to 2.47 mg/g. Maximum dye adsorption capacity of the durian skin was found to increase from 3.78 to 6.40 mg/g, with increasing solution pH. Equilibrium isotherm data were analyzed according to Langmuir and Freundlich isotherm models. The sorption equilibrium was best described by the Freundlich isotherm model with maximum adsorption capacity of 7.23 mg/g and this was due to the heterogeneous nature of the durian skin surface. Kinetic studies indicated that the sorption of MB dye tended to follow the pseudo second-order kinetic model with promising correlation of 0.9836 &lt; R2 &lt; 0.9918.

scholarly journals Mg-Cr Layered Double Hydroxide with Intercalated Oxalic Anion for Removal Cationic Dyes Rhodamine B and Methylene Blue

2020 ◽  
Vol 9 (1) ◽  
pp. 85-94
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Layered Double Hydroxide ◽  
Rhodamine B ◽  
Physical Adsorption ◽  
Dye Adsorption ◽  
Kinetic Studies ◽  
Economic Feasibility ◽  
Order Kinetic ◽  
Double Hydroxide

A MgCr-based layered double hydroxide (LDH) was synthesized by a coprecipitation method, followed by an intercalation process using an oxalic anion. The materials were characterized using X-ray diffraction analysis, FT-IR spectroscopy, and pH pzc measurement. The materials were then applied as adsorbents for removal of methylene blue (MB) and rhodamine B (RhB) from aqueous solution. Pristine Mg/Cr LDH exhibited RhB adsorption capacity of 32.154 mg g⁻1, whereas the use of intercalated Mg/Cr LDH caused an increase in the capacity (139.526 mg g⁻1). Kinetic studies indicated that the dye adsorption using both LDHs followed a pseudo-second-order kinetic model; the K2 values of pristine and modified Mg/Cr LDH for RhB and MB were 6.970, 0.001, 0.426, and 2.056 g mg⁻1 min⁻1, respectively. The thermodynamic study identified that the adsorption of both dyes onto the LDHs was a spontaneous process and can be classified as physical adsorption with adsorption energies of <40 kJ/mol. Moreover, the desorption and regeneration experiments indicated the high economic feasibility and reusability of the LDHs. By using HCl as the optimal solvent, the LDHs could desorb as much as 98% of the dye and could be used as adsorbents with high adsorption capacity over three cycles.

scholarly journals Fast Removal of Co2+ and Ni2+ from Aqueous Solution Using Partial Carbonized Nanoporous Resin

2015 ◽  
Vol 10 (3) ◽  
pp. 729-737
Author(s):  
Imed Ghiloufi
Keyword(s):  
Electron Microscopy ◽  
Metal Ion ◽  
Sol Gel ◽  
Kinetic Studies ◽  
Ion Concentration ◽  
Order Kinetic ◽  
Effective Parameters ◽  
Order Kinetic Model ◽  
Adsorption Of Co2 ◽  
Organic Xerogel

Partial carbonized nanoporous resin (PCNR-150), based on organic xerogel compounds, was prepared at 150 ºC by sol–gel method from pyrogallol and formaldehyde mixtures in water using perchloric acid as catalyst. The PCNR-150 was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transformed infrared spectroscopy (FTIR) and nitrogen porosimetry. The metal uptake characteristics were explored using well-established and effective parameters including pH, contact time, initial metal ion concentration, and temperature. Optimum adsorptions of Co2+ and Ni2+, using PCNR-150 as adsorbent, were observed at pH 5 and 7, respectively. Langmuir model gave a better fit than the other models, and kinetic studies revealed that the adsorption is fast and its data are well fitted by the pseudo-second-order kinetic model and thermodynamic properties, i.e., ΔGo, ΔHo, and ΔSo, showed that adsorption of Co2+ and Ni2+ onto PCNR-150 was endothermic, spontaneous and feasible in the temperature range of 300–328 K.

scholarly journals Titania-Based Hybrid Materials with ZnO, ZrO2 and MoS2: A Review

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2295 ◽  
Author(s):  
Adam Kubiak ◽  
Katarzyna Siwińska-Ciesielczyk ◽  
Teofil Jesionowski
Keyword(s):  
Hybrid Systems ◽  
Hybrid Materials ◽  
Binary Systems ◽  
Sol Gel ◽  
Morphological Properties ◽  
Oxide Systems ◽  
Practical Applications ◽  
Current State ◽  
Physico Chemical ◽  
Electrospinning Method

Titania has properties that enable it to be used in a variety of applications, including self-cleaning surfaces, air and water purification systems, hydrogen evolution, and photoelectrochemical conversion. In order to improve the properties of titanium dioxide, modifications are made to obtain oxide/hybrid systems that are intended to have the properties of both components. In particular, zinc oxide, zirconia and molybdenum disulfide have been proposed as the second component of binary systems due to their antibacterial, electrochemical and photocatalytic properties. This paper presents a review of the current state of knowledge on the synthesis and practical utility of TiO2-ZnO and TiO2-ZrO2 oxide systems and TiO2-MoS2 hybrid materials. The first part focuses on the hydrothermal method; then a review is made of the literature on the synthesis of the aforementioned materials using the sol-gel method. In the last section, the literature on the electrospinning method of synthesis is reviewed. The most significant physico-chemical, structural and dispersive-morphological properties of binary hybrid systems based on TiO2 are described. A key aim of this review is to indicate the properties of TiO2-ZnO, TiO2-ZrO2 and TiO2-MoS2 hybrid systems that have the greatest importance for practical applications. The variety of utilities of titania-based hybrid materials is emphasized.

scholarly journals Hybrid materials precursor to natural bentonite in the decontamination of Alizarin Yellow from aqueous solutions

2021 ◽  
Vol 27 (6) ◽  
pp. 210104-0
Author(s):  
Ralte Malsawmdawngzela1 ◽  
Sarikokba ◽  
Thanhmingliana ◽  
Diwakar Tiwari ◽  
Seung Mok Lee
Keyword(s):  
Hybrid Materials ◽  
Batch Reactor ◽  
Background Electrolyte ◽  
Kinetic Studies ◽  
Hexadecyltrimethylammonium Bromide ◽  
Order Kinetic ◽  
Removal Capacity ◽  
Alizarin Yellow ◽  
Order Kinetic Model ◽  
Parametric Studies

The present study aims to investigate the insights of Alizarin Yellow removal by hybrid materials precursor to natural bentonite. The hybrid materials employed are bentonite modified with hexadecyltrimethylammonium bromide (HDTMA) (BnH) and aluminium pillared HDTMA bentonite (BnAH). Surface morphology of materials are obtained with scanning electron microscopy-Energy dispersive X-ray analysis (SEM-EDX). The batch reactor operations conducted in the removal of Alizarin Yellow by these solids for various parametric studies which enabled to deduce the mechanism involved at solid/solution interface. Sorption capacity and selectivity was increased significantly using hybrid materials in the removal of AY. Hybrid materials showed very high removal capacity of AY and apparently unaffected at varied pH (4.0−10.0) and sorptive concentrations 1.0 to 25.0 mgL<sup>-1</sup>. Kinetic studies indicated that an apparent equilibrium occurred within 5–10 min of contact and the kinetic data was better fitted to the pseudo-second-order kinetic model. The percent removal of AY was not affected by increasing the background electrolyte (NaCl) concentration to 0.1 molL<sup>-1</sup> and in presence of several co-existing ions. It is revealed that the hybrid materials are found more organophilic and AY molecule bound with strong forces at the surface of hybrid materials.

scholarly journals Statistical Modeling and Kinetic Studies on the Adsorption of Reactive Red 2 by a Low-Cost Adsorbent: Grape Waste-Based Activated Carbon Using Sulfuric Acid Activator-Assisted Thermal Activation

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Seyyed Alireza Mousavi ◽  
Davood Shahbazi ◽  
Arezoo Mahmoudi ◽  
Parviz Mohammadi ◽  
Tooraj Massahi
Keyword(s):  
Activated Carbon ◽  
Statistical Modeling ◽  
Low Cost ◽  
Dye Adsorption ◽  
Kinetic Studies ◽  
Type I ◽  
Order Kinetic ◽  
Grape Waste ◽  
Pseudosecond Order ◽  
Reactive Red 2

The efficiency of activated carbon produced from grape waste as a low-cost, nontoxic, and available adsorbent to remove Reactive Red 2 from aqueous solution has been investigated. The prepared activated carbon has been characterized by FTIR, SEM, and BET. The results of characterization indicate the successful conversion of grape waste into mesoporous AC with desirable surface area consist of different functional groups. The results of statistical modeling displayed high R 2 value of 0.97% for dye removal that shows the developed model has acceptable accuracy. The effect of independent variables indicated that the highest adsorption (96.83%) obtained at pH 3, adsorbent dosage of 12.25 g/L, and initial dye concentration of 100 mg/L when the adsorption time was 90 min. The results of isotherms modeling showed that the data fit well with the Langmuir (type II). The kinetic studies using pseudofirst-order and pseudosecond-order models pointed out that the type (I) of pseudosecond-order kinetic model provided the best fit to the adsorption data. Parameters of thermodynamics including Gibbs energy ( Δ G ° ) and k o were calculated. The values of Δ G ° indicated that the dye adsorption of RR2 is spontaneous. The agricultural wastes due to special points such as low-cost, availability, and high ability to produce an adsorbent with high efficiency to remove dye can be proposed for water and wastewater treatment.

Sol–Gel Synthesis of Mesoporous Silica–Iron Composite: Kinetics, Equilibrium and Thermodynamics Studies for the Adsorption of Turquoise-Blue X-GB Dye

2020 ◽  
Vol 234 (2) ◽  
pp. 233-253 ◽  
Author(s):  
Muhammad Asif Tahir ◽  
Haq Nawaz Bhatti ◽  
Irshad Hussain ◽  
Ijaz Ahmad Bhatti ◽  
Muhammad Asghar
Keyword(s):  
Mesoporous Silica ◽  
Sol Gel ◽  
Average Particle Size ◽  
Dye Adsorption ◽  
Sem Analysis ◽  
Average Particle ◽  
Order Kinetic ◽  
Isothermal Model ◽  
Order Kinetic Model ◽  
Sol Gel Synthesis

AbstractMesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m2/g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

Sign in / Sign up

Export Citation Format

Share Document