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Removal of Methyl Violet from aqueous solutions using poly (acrylic acid-co-acrylamide)/attapulgite composite
Removal of Methyl Violet from aqueous solutions using poly (acrylic acid.co-acrylamide)/attapulgite composite

Yongsheng Wang,Li Zeng,Xuefeng Ren,Hai Song,Aiqin Wang,
Yongsheng Wang
,Li Zeng,Xuefeng Ren,Hai Song,Aiqin Wang

环境科学学报(英文版) , 2010,
Abstract: The adsorption of Methyl Violet (MV) cationic dye from aqueous solution was carried out by using crosslinked poly (acrylic acid-co-acrylamide)/attapulgite (Poly(AA-co-AM)/ATP) composite as adsorbent. The factors influencing adsorption capacity of the composite such as pH, concentration of the dye, temperature, contact time, adsorbent dosage, ionic strength and surfactant were systematically investigated. The equilibrium data fitted very well to the Langmuir isotherm and the maximum adsorption capacity reach...
Flocculation Efficiency of Poly(Acrylamide-Co-Acrylic Acid) Obtained by Electron Beam Irradiation  [PDF]
Gabriela Craciun,Elena Manaila,Maria-Daniela Stelescu
Journal of Materials , 2013, DOI: 10.1155/2013/297123
Abstract: A correlation between physicochemical characteristics of flocculants obtained by electron beam irradiation and their efficiency for wastewater treatment is presented. For real wastewater treatment, our interest was focused upon total suspended solids, fatty matter, and chemical oxygen demand. Flocculation studies were carried out using a standard jar test. A treatment option based on poly(acrylamide-co-acrylic acid) for wastewater taken from a slaughterhouse plant is presented. 1. Introduction Wastewater treatment is a major problem around the world. Growing along with the population growth, industries create environmental problems and health hazards for the population. Hence, environmental concerns behoove scientists and engineers to develop materials and methods to lower the extent of pollution of the environment [1]. Coagulation and flocculation still play a dominant role in many water and Wastewater treatment schemes. Because of the complex interdependence of numerous factors inherent in the coagulation and flocculation processes, a well understanding of the phenomena involved is essential. Coagulation is the process whereby destabilization of given suspension or solution is affected; that is, the function of coagulation is to overcome the factors that promote the stability of a given system. The manifestation of destabilization depends on the particular system; for example, in the case of disperse suspensions or solutions, visible floc or precipitate formation occurs; in the case of highly concentrated suspensions, dewatering of the sludge mass occurs, and so on. Flocculation is the process whereby destabilized particles, or particles formed as a result of destabilization, are induced to come together, make contact and thereby form large(r) agglomerates. In this case, the manifestation of destabilization is realized in practicable terms: in effect, flocculation accelerates floc formation, influences the physical characteristics of flocs formed (e.g., their strength, size, and density), and governs the final concentration of destabilized particles. In water and Wastewater treatment, coagulation and flocculation phenomena are extremely important [2]. In Wastewater treatment, flocculation is essential. Flocculating agents, or flocculants, are important components which cause flocculation, the process of bringing together small particles to form larger particles by adding small quantities of chemicals in water and Wastewater treatment [3, 4]. Flocculants are classified into inorganic and organic categories. Though the inorganic flocculants (also called
Synthesis and characterization of acrylamide/acrylic acid hydrogel and its application for crystal violet dye adsorption
Klinpituksa, P.,Chaiyotha, P.,Chaisuksan, Y.
Songklanakarin Journal of Science and Technology , 2006,
Abstract: Acrylamide/acrylic acid (AAm/AAc) hydrogel was prepared by free radical polymerization in aqueous solution of acrylamide and acrylic acid as a comonomer using ammonium persulfate and N,N,N’,N’-tetramethylethylenediamine as an initiator system and N,N’-methylenebisacrylamide as a crosslinker at room temperature. The hydrogels were prepared from acrylamide/acrylic acid with the ratios of 2.5/97.5, 5/95, 10/90, 20/80, 30/70, 40/60 and 50/50. The swelling property and the equilibrium water content of the hydrogel were determined in distilled water and in a solution of pH 3, 5, 7 and 8 for 96 hours. The result showed that the maximum swelling and equilibrium water content of the hydrogel obtaining from AAm/ AAc in the ratio of 10/90 were found to be 3,945% and 0.9747 at pH 8, respectively. The adsorption capacity of AAm/AAc (10/90) for crystal violet was also investigated at pH 3, 5, 7, 8 and 9 for 48 hours. It was found that the optimum adsorption capacity of the hydrogel was in the range of 5-8. The adsorption rate was 90% of the sorption completion within 48 hours. The equilibrium data fitted well to the Langmuir isotherm with the maximum adsorption capacity of 116.28 mg/g at pH 7.
Improvement in the Water Retention Characteristics of Sandy Loam Soil Using a Newly Synthesized Poly(acrylamide-co-acrylic Acid)/AlZnFe2O4 Superabsorbent Hydrogel Nanocomposite Material  [PDF]
Shaukat Ali Shahid,Ansar Ahmad Qidwai,Farooq Anwar,Inam Ullah,Umer Rashid
Molecules , 2012, DOI: 10.3390/molecules17089397
Abstract: The use of some novel and efficient crop nutrient-based superabsorbent hydrogel nanocomposites (SHNCs), is currently becoming increasingly important to improve the crop yield and productivity, due to their water retention properties. In the present study a poly(Acrylamide-co-acrylic acid)/AlZnFe2O4 superabsorbent hydrogel nanocomposite was synthesized and its physical properties characterized using Energy Dispersive X-ray (EDX), FE-SEM and FTIR spectroscopic techniques. The effects of different levels of SHNC were studied to evaluate the moisture retention properties of sandy loam soil (sand 59%, silt 21%, clay 19%, pH 7.4, EC 1.92 dS/m). The soil amendment with 0.1, 0.2, 0.3 and 0.4 w/w% of SHNC enhanced the moisture retention significantly at field capacity compared to the untreated soil. Besides, in a separate experiment, seed germination and seedling growth of wheat was found to be notably improved with the application of SHNC. A delay in wilting of seedlings by 5–8 days was observed for SHNC-amended soil, thereby improving wheat plant growth and establishment.
Porous poly(methylmethacrylate) and poly(methylmethacrylate-co-acrylamide)
Nikoli? Ljubi?a,Nikoli? Vesna,Stankovi? Miroslav,Todorovi? Zoran
Hemijska Industrija , 2006, DOI: 10.2298/hemind0612327n
Abstract: The characteristics of two types of porous polymers: poly(methyl methacrylate) and copolymers of methyl methacrylate and acrylamide were investigated in this study. Poly(methyl methacrylate) was synthesized in suspension, using ethylene glycol dimethacrylate as the cross-linking agent, poly(vinyl pyrrolidone) as the protective colloid, and benzoyl peroxide as the initiator. The synthesis of poly(methyl methacrylate-co-acrylamide) was initiated in emulsion in the presence of dioctyl sulfosuccinate sodium salt, followed by a sol-gel process, and completely reacted to the solid state. Potassium persulfate was used as the initiator, and tetramethylol glycoluril as the cross-linking agent. Both types of syntheses were carried out in the presence of ethyl acetate. The porosity, specific surface and distribution of the pore sizes of the obtained polymers were determined by mercury porosimetry. The polymers were used as inert carriers for the immobilization of enzymes and whole cells of Saccharomyces cerevisiae yeast.
Vinyl Acetate-Acrylic Acid Copolymer for Enhanced Oil Recovery  [PDF]
Gerard T. Caneba, Jay Axland
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2002, DOI: 10.4236/jmmce.2002.12007
Abstract: This paper pertains to the possible use of newly-synthesized vinyl acetate/acrylic acid (VA/AA) copolymer to help recover trapped crude oil, an important mineral resource. The proposed approach is to use the copolymer as a foaming surfactant (in water or brine), which will be driven by a gas, such as carbon dioxide or nitrogen. Neutralized forms of the copolymer result in an anionic surfactant, which has been found to have minimal adsorption onto the rock matrix. The neutralized VA/AA copolymers synthesized in this study are found to outperform other anionic surfactants and even more adsorbing nonionic surfactants. Due to the long chain nature of the hydrophilic groups of nonionic surfactants, they are found to produce better foams than anionic ones. Since VA/AA copolymers have long chain hydrophilic groups, it is not surprising that they are good foaming agents as well. Optical microscopy of VA/AA emulsions reveal that they form microscopic network surface structures, which are presumably due to liquid crystalline formation in macromolecular scale.
Hydrogels obtained from acrylamide, maleic acid, acrylic acid and octylmonoitaconate: synthesis, absorbent capacity and pH variations in copper sulfate solutions
Rojas de Gascue,Blanca; Ramírez,Marvelis; Aguilera,Rocelis; García,Augusto; Prin,José Luis; Lias,José; Torres,Carlos; Katime,Issa;
Revista Técnica de la Facultad de Ingeniería Universidad del Zulia , 2007,
Abstract: abstract acrylamide (aam)/maleic acid (am), acrylic acid (aac)/maleic acid (am) and acrylic acid (aac)/2 - methylenebutanedioic acid octylesther (mi-8) hydrogels were sinthetysed in presence of amonium persulfate as initiator and n,n?-methylenebisacrylamide as crosslinking agent. the grade of hydrogels swelling was determined by two test at diferent temperatures: 25 and 37°c. the hydrogels swelling also was studied in divalents cations salts solutions, like copper by way of plasma spectroscopy emition. the swelling of synthesised hydrogels test shows isothermal that extends asinthotically to the equilibrium. it was demonstrated that the maleic acid content had a direct influence in the swelling properties (an increment of 30% in am rise the content of water in the hydrogel in 12%). respect to the copper cations adsorption, we found that the concentration decrease in the initial solution after to be in contact with the hydrogels. moreover, ph variation was measured allowing understand the reaction mechanism between the hydrogels and metallic ions
Amidopoly Ethylamines as Corrosion Inhibitors for Zinc Dissolution in Different Acidic Electrolytes
Abdallah,M.; El-Etre,A.Y.; Moustafa,M.F.;
Portugaliae Electrochimica Acta , 2009,
Abstract: the effect of some amidopoly ethylamine, with different numbers of ethylamine units, on the corrosion of zinc electrode in zncl2, nh4cl and (zncl2 + nh4cl) electrolytes has been studied using galvanostatic polarization measurements. the inhibition efficiency was found to increase with increasing concentration, number of ethylamine units per molecule and with decreasing the temperature. inhibition is explained on the basis of adsorption of amidopoly ethylamine molecules on the zinc electrode surface through their ethylamine groups. the inhibitors are adsorbed on the zinc electrode surface according to langmuir adsorption isotherm. some thermodynamic parameters are calculated and explained for the tested systems from the data obtained at different temperatures.
Amidopoly Ethylamines as Corrosion Inhibitors for Zinc Dissolution in Different Acidic Electrolytes  [cached]
M. Abdallah,A.Y. El-Etre,M.F. Moustafa
Portugaliae Electrochimica Acta , 2009,
Abstract: The effect of some amidopoly ethylamine, with different numbers of ethylamine units, on the corrosion of zinc electrode in ZnCl2, NH4Cl and (ZnCl2 + NH4Cl) electrolytes has been studied using galvanostatic polarization measurements. The inhibition efficiency was found to increase with increasing concentration, number of ethylamine units per molecule and with decreasing the temperature. Inhibition is explained on the basis of adsorption of amidopoly ethylamine molecules on the zinc electrode surface through their ethylamine groups. The inhibitors are adsorbed on the zinc electrode surface according to Langmuir adsorption isotherm. Some thermodynamic parameters are calculated and explained for the tested systems from the data obtained at different temperatures.
Deposition and Characterisation of Nitrogen-Doped Zinc Oxide Thin Films by MOCVD Using Zinc Acetate—Ammonium Acetate Precursor  [PDF]
U. S. Mbamara, O.O. Akinwumi, E.I. Obiajunwa, I.A.O. Ojo, E.O.B. Ajayi
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.38089
Abstract: The synthesis and comprehensive analysis of nitrogen-doped zinc oxide thin films grown from a compound precursor of zinc acetate and ammonium acetate has been reported. The precursor was processed in different ratios of the zinc acetate-ammonium acetate additives, and each combination was used to deposit a thin film using metalorganic chemical vapour deposition (MOCVD) method. The produced thin films were characterised using Rutherford backscattering (RBS) spectroscopy, uv-visible spectrometry, x-ray diffractometry, four point probe measurements and optical microscopy. The deposited thin films showed a fairly consistent zinc:oxygen:nitrogen ratio of 4.4:3.7:1, the film structures were quasicrystalline and the sheet resistivities were high, while other familiar characteristics like optical transmittance, bandgap, thermal stability, etc. were maintained in the grown films. Applications in device fabrication and active sensor devices were hence envisaged as the emergent potentials of the thin films.
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