Adsorption of Cationic Dye from Aqueous Solutions by Green pH Responsive Hydrogels Based on Poly(2-acrylamido-2-methyl-1propanesulfonic acid (original) (raw)
Related papers
ACS Omega, 2020
A green composite of organically modified bentonite supported by Co 3 O 4 nanoparticles (OB/Co) was successfully fabricated and investigated as a potential eco-friendly, low-cost adsorbent and photocatalyst for promising removal of both malachite green dye (MG.D) and Cr(VI) ions. The composite showed high adsorption properties and achieved experimental q max values of 223 and 139 mg/g for MG.D and Cr(VI) after equilibration times of 360 min and 480 min for the inspected contaminants, respectively. The kinetic and equilibrium inspection reflected the best description of their adsorption behaviors by the pseudo-first-order kinetic model and the Langmuir isotherm model, respectively. This revealed favorable and homogeneous uptake of both MG.D and Cr(VI) in a monolayer form with theoretical Langmuir q max values of 343.6 and 194.5 mg/g, respectively. The theoretical adsorption energies of MG.D (0.6 kJ/ mol) and Cr(VI) (0.5 kJ/mol) from the Dubinin−Radushkevich (D−R) model revealed physisorption properties that might be resulted from some types of Coulombic attractive forces, achieving theoretical q max values of 226.5 and 144.6 mg/g, respectively. The suggested adsorption mechanism was confirmed by the main mathematical parameters of thermodynamic studies that revealed physical, spontaneous, and exothermic uptake processes. Also, the composite showed high photocatalytic performance under visible light, which resulted in a 100% removal percentage of 100 mg/L of MG.D and Cr(VI) after about 180 and 240 min, respectively, from the adsorption equilibrium time.
Spherical polyacrylamide (PAM) nanoparticles were prepared by inverse emulsion polymerization and were found to have an average particle size of 20 nm. In situ inverse emulsion polymerization of acrylamide in the presence of metal oxides nanoparticles (TiO 2 and ZnO, either individually or in a mixture) was performed. Transmission electron microscope images clearly confirmed the formation of core/shell nanocomposite structures with inner metal oxide cores coated with a polyacrylamide shell. The composites were further cross-linked to prevent structural deformation in water. The water absorbencies of the prepared composites were 1660, 900, 1000 and 700% for PAM, TiO 2 /PAM, ZnO/ PAM, and TiO 2 –ZnO/PAM core/shell nanocomposites, respectively. The water decontamination efficiency of the prepared composites was investigated using organic dyes as models of organic contaminants. The decolorization efficiency of the prepared composites was investigated in the dark and under illumination. The nanocomposites showed good ability for photodecolorization, especially the titania nanocomposite, which showed the best ability to photodecolorize Black T and Indigo dyes. A synergetic effect between the adsorption properties of the polymer and the photocatalytic activity of the metal oxides is proposed.
7 – Renewable Resource-Based Advanced Functional Composites and Nanocomposites
Polymers and their composites have in fact percolated every aspect of our daily life. The extensive use of polymers and their composites in the manufacturing of basic utilities starting from carrying bags to engineered materials has revolutionized the human life style as well as the industrial scenario. The usage of polymers and composites has deeply influenced the development of modern technological societies leading to a high standard of living. Cutting edge research is being carried out to develop and deploy polymers and their composites in critical areas of human endeavor such in medicine, medical appliances, energy and environment. Engineered materials using advanced polymers and their composites are finding extensive use in sectors like automotives, aerospace, electronics, and electrical devices. The Advanced Functional Polymers and Composites: Materials, Devices and Allied Applications Vol. 1 and Vol. 2 have been compiled to broadly explore the latest developments in the field of polymeric and composite materials. These two volumes of the book edition will prove to be highly useful for various disciplines of science, engineering, biomedicine, dental medicine, orthopedics, nanotechnology, biomedical engineering, etc. Volume 2, hopefully, will evoke interest from scientists working in the fields of chemistry, environmental chemistry, polymer chemistry, electrochemistry, material science including voltammetric nanoelectrodes, photocatalytic materials and reactors, adsorption of pollutants, environment pollution control, support vector machines as applied to polymers, simulation of ion exchange membrane etc. Based on thematic topics, volume 2 contains the following 11 chapters: Chapter 1: This chapter reviews the recent advances in the field of polymer based electrochemical sensors, in particular nanoelectrode ensembles (NEEs). Synthetic approaches, principles of functioning, specific advantages and limits of NEEs are critically discussed. Useful examples of application to the determination of trace and ultratrace concentrations of inorganic and organic electroactive molecules of interest for environmental and biomedical analysis are given, along with prospects in the future development of polymer based electrochemical sensors. Chapter 2: This chapter gives an introduction of water pollution and photocatalysis, advantages and disadvantages of photocatalytic reactors based on conventional UV sources and solar light. Besides the potential advantages of UV-LED and designing of photocatalytic reactors based on UV-LED source, two types of reactor such as dispersion and immobilized catalyst film type are presented. Furthermore, the detailed mechanisms involved in the degradation of RhB, CR and MG dye using these photocatalytic reactors has also been addressed. Complimentary Contributor Copy Inamuddin x Chapter 3: In this chapter, the uses of chitosan and its three types of derivatives in the field of environmental protection is reviewed. Chapter 4: In this chapter, preparation of methacrylate monoliths, monolith properties and formats on different scales are presented. Several biotechnological examples such as monitoring of metal organic complexes, proteins, plasmid DNA, viruses, virus like particles are also described. Chapter 5: In this chapter, the advanced functional applications of coordination polymers in biological, electronic, magnetic, optical, sensor and catalytic areas are reviewed. Chapter 6: In this chapter, some possible areas of polymer composites where support vector machines can be fruitfully employed have been identified and the scope of such employment has been discussed. Chapter 7: This chapter provides a brief outline of vegetable oils composites and nanocomposites obtained with nanoclays, conducting polymers, metal nanoparticles/metal oxides, carbon nanotubes and natural fibres, while focussing on their applications, mainly as coating materials. Chapter 8: In this chapter, history, theory and applications of heavy metal ion selective electrodes are reviewed. Chapter 9: In this chapter, some of the cost effective sorbents used for the removal of toxic species from ground water system are reviewed. Chapter 10: In this chapter, the network simulation method is described to simulate and interpret the electrochemical impedance of ion-exchange membrane systems. Chapter 11: In this chapter, layer materials used in the thin layer chromatographic/ high performance thin layer chromatographic analysis of biomolecules using various stationary and mobile phases is presented. Complimentary Contributor Copy ACKNOWLEDGMENTS I am profoundly indebted to the grace of the Almighty, the 'One Universal Being', who inspires entire humanity to knowledge, and who has given me the required favor to complete this work. This book is the outcome of remarkable contributions of experts of interdisciplinary fields of science and engineering, with comprehensive, in-depth and up-to-date research works and reviews. I am thankful to all the contributing authors and their co-authors for their esteemed contribution to this book. I would also like to thank all publishers, authors and others who have granted us permission to use their figures/tables. Although sincere efforts have been made to obtain copyright permissions from the respective owners and to include citations with the reproduced materials, I would still like to offer my sincere apologies to any copyright holder whose rights may have been unknowingly infringed. I would like to express my deep sense of gratitude to my mentors, Mr. Farooq Ali (my High School mathematics teacher), late Mr. Sanaullah Khan and Dr. H.S. Yadav (Intermediate and Graduation chemistry teachers, respectively), who imbued in me a lifelong interest in chemistry. I am grateful to Prof.
Polymer Composites, 2014
Organophilic montmorillonite (OMMT) was synthesized by cationic exchange reaction of Na 1 -MMT and vinyl benzyl triethyl ammonium chloride (VBTAC) as a reactive organic modifier in an aqueous solution. A series of styrene (St)/acrylic acid (AA)/OMMT nanocomposite hydrogel containing different wt % of OMMT was synthesized through in situ polymerization using g-ray. The samples were characterized using Fourier transform infrared (FTIR), X-ray powder diffraction (XRD), and transmission electron microscope (TEM), whereas thermal stability was examined by thermogravimetric analysis (TGA). The adsorption capacity and rate for both Acid Green B (anionic) and Maxilon C.I. Basic (cationic) dye including adsorption kinetics and isotherm were investigated at 30 C. TEM measurements showed spherical nanosized particles of average diameter 30-40 nm and XRD suggested the formation of exfoliated nanocomposite. TGA measurements showed that the addition of OMMT did not enhance the thermal stability where the onset temperature of the degradation for all samples was around 125 C. The effect of some important parameters on dye adsorption such as solution pH, initial dye concentration, and contact time was investigated. The equilibrium data obtained in batch experiments were correlated to Langmuir and Freundlich isotherm equations. Results showed that the adsorption of Acid Green B fitted well to the Langmuir model while the adsorption pattern of Maxilon C.I. Basic followed the Freundlich isotherm, which suggests heterogeneity of the adsorption sites on the nanocomposite. POLYM. COMPOS., 00:000-000, 2014.
Scientific reports, 2021
MOFs compounds with open metal sites, particularly Cu-BTC, have great potential for adsorption and catalysis applications. However, the powdery morphology limits their applications. One of the almost new ways to overcome this problem is to trap them in a standing and flexible aerogel matrix to form a hierarchical porous composite. In this work, Cu-BTC/CNC (crystalline nanocellulose) and Cu-BTC/NFC (nanofibrillated cellulose) aerogel composites were synthesized using a direct mixing method by the addition of Cu-BTC powder to the liquid precursor solution followed by gelation and freeze-drying. Also, pure nanocellulose aerogels (CNC and NFC aerogels) have been synthesized from cellulose isolated from peanut shells. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectra, and X-ray diffraction (XRD) were utilized to evaluate the structure and morphology of the prepared materials. The adsorption ability of pure CNC aerogel and Cu-BTC/NFC aerogel composite for organic dye (Congo Red) and heavy metal ion (Mn 7+) was studied and determined by the UV-Vis spectrophotometry and inductively-coupled plasma optical emission spectrometry (ICP-OES), respectively. It was concluded that Cu-BTC/NFC aerogel composite shows excellent adsorption capacity for Congo Red. The adsorption process of this composite is better described by the pseudosecond-order kinetic model and Langmuir isotherm, with a maximum monolayer adsorption capacity of 39 mg/g for Congo Red. Nevertheless, CNC aerogel shows no adsorption for Congo Red. Both CNC aerogel and Cu-BTC/NFC aerogel composite act as a monolith standing solid reducer, which means they could remove permanganate ions from water by reducing it into manganese dioxide without releasing any secondary product in the solution. Metal-organic frameworks (MOFs) are porous crystalline polymer networks of metal nodes (metal ions or clusters) connected to multidentate organic linkers, which are themselves linked by strong covalent bonds forming one-, two-, or three-dimensional networks 1-3. MOFs are also known as porous coordination polymers (PCPs) or porous coordination networks (PCNs) 4-6. In addition to combining the beneficial properties of organic and inorganic ingredients, they show unique properties that exceed expectations of a simple mixture of these parts 5,7. Due to their specific characteristics including their record-breaking surface areas (more than 7000 m 2 /g) 8 , ultrahigh porosities 9 , low density 10 , high thermal stability 11 , and tunable pore structure 12 , MOFs have received specific attention for many applications such as gas separation and storage 13 , catalysis 14 , adsorption 15,16 , energy storage 17 , drug delivery 18-20 , chemical sensing 21,22 and so on 23. Among the various types of MOFs, copper benzene tricarboxylate Cu-BTC or Cu 2 (BTC) 3 (also called HKUST-1 or MOF-199) 24,25 is one of the distinguished structure together with the IRMOF series. Cu-BTC was first reported in 1999 by Chui et al. 26 and has attracted considerable attention both theoretically and experimentally 27. Due to its open metal sites and large pore windows 28 , Cu-BTC has particular potential for
Magnetochemistry
In the present study, a ternary magnetic nanocomposite (SiO2/MnFe2O4/ZIF-8) was synthesized via the embedding of the SiO2/MnFe2O4 nanocomposite within the metal–organic framework (ZIF-8). The synthesized nanocomposite was characterized using suitable techniques including FT-IR, XRD, SEM, TEM, VSM, and BET. The nanocomposite showed a high surface area (SBET = 831 m2·g−1) and superparamagnetic behavior (23.7 emu·g−1). All characterization techniques confirmed the successful combination of three nanocomposite parts (MnFe2O4, SiO2, and ZIF-8). The nanocomposite was examined for the adsorption of organic dyes, malachite green (MG) and methyl red (MR), from aqueous solutions. The adsorption conditions including ionic strength, contact time, pH, and adsorbent dosage were optimized by studying their change effect. The SiO2/MnFe2O4/ZIF-8 nanocomposite showed high adsorption capacities (1000.03 and 1111.12 mg/g) for the removal of MG and MR, respectively, from water. The isotherm and kinetics...
Catalytic activity of a soft composite material: Nanoparticle location–activity relationship
Materials Science and Engineering: B, 2008
A nanostructure, fiber-shaped morphology of a conjugated polymer (poly-5 amono-ortho-cresol, PAOC) has been synthesized using palladium acetate as the oxidizing agent. A one pot, in situ chemical synthesis approach has been utilized in which palladium acetate was reduced during the polymerization process of 5-amono-o-cresol (AOC) and formed well dispersed palladium nanoparticles in the polymer fibers. The resultant composite material was characterized by means of optical, thermo and micro-analytical techniques. The elemental identity of the nanoparticles was determined by means of electron energy loss spectroscopy (EELS) mapping using analytical transmission electron microscopy (TEM). Subsequently, the sample was used as a catalyst for a model gas-phase hydrogenation reaction. The activation and deactivation behaviour of the catalyst as a function of temperature is discussed in the light of different phase transition points of the polymer as well as the orientation of the palladium nanoparticles. The fact that palladium nanoparticles (∼2 nm) were uniformly distributed throughout the polymer matrix makes the composite material an excellent hybrid structure.
Efficient and recyclable AuNPs/aminoclay nanocomposite catalyst for the reduction of organic dyes
Surfaces and Interfaces, 2022
Industrial dye effluents and organic pollutants pose serious environmental threats for which efficient catalytic adsorbents have been indispensable in treating them. In the present work, the synthesis of gold nanoparticles (AuNPs) dispersed over aminopropyl-functionalized magnesium phyllosilicate (AMP) composites (AuNPs/AMP NC) is reported, involving the organic-inorganic hybrid structure with the strategy of AuNP formation over AMP clay. The AuNPs decorated AMP hybrid nanocomposite was characterised by XRD, FTIR, TGA, UV-Visible, SEM-EDAX, and TEM techniques. The presence of a surface plasmon resonance (SPR) absorption band at 520 nm in UV-Visible spectra revealed the formation of AuNPs over AMP support, which was supported by XRD results. The average particle size of AuNPs with spherical morphology was in the range of 3 nm, respectively. The catalytic performance of the AuNPs/AMP NC was studied through the reduction of malachite green (MG), phenol red (PR), rhodamine B (RhB), rhodamine 6 G (Rh6G), and Congo red (CR) in the presence of NaBH4, respectively. The progress of reductive dye degradation was monitored via UV–Vis spectrophotometry. The kinetic data was analysed and apparent rate constants were determined for the respective dyes. The reduction efficiency of the nanocatalyst over MG, PR, RhB, Rh6G, and CR, in the presence of NaBH4 was determined as > 98%, respectively. Such prolific nanocomposite catalysts could be employed as an alternative to toxic dye and organic component degradation in environmental treatment.
International Journal of Eco-Innovation in Science and Engineering
Fe3O4 Nanocomposite Hydrogels were prepared by free radical polymerization using N-tert-amyl acrylamide , Acrylamide and Sodium acrylate monomers at 60OC. Fe3O4 NPs was intercalated via in situ method. The synthesized nanocomposite Hydrogels conformed by FT-IR spectroscopy. Surface morphology of the nanocomposite hydrogels indicated the ferrate nanoparticles are intercalated uniformly throughout the polymer matrix. The XRD pattern of the hydrogel showed the presence of nanoparticles in the matrix with certain crystallinity nature. UV-visible absorption studies reveal the catalytic activity of Methylene Blue dye molecules in the aqueous medium by the Nanocomposite hydrogels.
DESALINATION AND WATER TREATMENT, 2018
A novel environmentally friendly super-paramagnetic nano composite based on cross-linked poly (N-vinylpyrrolidone-co-maleic anhydride) (PNVPMA) was successfully prepared by simultaneous reaction of the PNVPMA copolymer with 3-aminobenzoic acid (3ABA), as a modifying agent, and ethylenediamine, as a cross linking agent, in the presence of Fe 3 O 4 nano particles and eggshell. The prepared materials were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Vibrating sample magnetometer (VSM) was used to measure the magnetic property of nano composite as a function of magnetic field. The uptakes of Pb (II) and Cd (II) on the nano composite were studied in a batch system. The influences of various factors including pH of solution, nano composite dosage, agitation time, and initial concentrations of Pb (II) and Cd (II) were also investigated. The maximum adsorption capacities (Q max) of Pb (II) and Cd (II) on the nano composite under the certain experimental conditions were 312.5 mg/g and 32.78 mg/g, respectively. The results showed that the experimental data of the Pb (II) and Cd (II) adsorption on the nano composite were in agreement with the Langmuir adsorption isotherm and second-order kinetic equations. The negative values of ΔG° for the adsorption of both Pb (II) and Cd (II) on the synthesized nano composite endorse that the adsorption processes are spontaneous and thermodynamically favorable. On the other hand, the positive values of ΔH° support the endothermic physical adsorption process.