Preparation and Hygroscopic Property of the Polyacrylamide/MgCl2 Hybrid Hydrogel

2012 ◽  
Vol 550-553 ◽  
pp. 904-907 ◽  
Author(s):  
Ying Wang ◽  
Li Ren Fan
Keyword(s):  
Magnesium Chloride ◽  
Chloride Concentration ◽  
X Ray Diffraction ◽  
Hybrid Hydrogel ◽  
Hygroscopic Property ◽  
Hygroscopic Swelling ◽  
Swelling Rate ◽  
Aqueous Solution Polymerization ◽  
Pseudo Second Order ◽  
Swelling Kinetic

Polyacrylamide/MgCl2 hybrid hydrogel desiccant was prepared from magnesium chloride and polyacrylamide by aqueous solution polymerization. The hybrid hydrogel was synthesized and characterized by X-ray diffraction. The effect of the experimental factors such as content of magnesium chloride, concentration of cross-linking agent, initiator content on hygroscopic performance of the hybrid hydrogel were investigated, furthermore, the hygroscopic swelling kinetic process of the hybrid hydrogel was studied. The results indicate that hybrid hydrogel possessed preferable hygroscopic property under the optimum conditions, the hygroscopic swelling degree achieving 172%. The hygroscopic swelling process of the hybrid hydrogel follows the kinetic pseudo-second-order model, in addition, the swelling rate decreases with the increase of relative humidity.

Preliminary Study of Preparation and Properties of Activated K-Feldspar-Filled Hydrogel Materials

2013 ◽  
Vol 734-737 ◽  
pp. 2141-2144
Author(s):  
Hui You Shen ◽  
Li Ren Fan ◽  
Bao Ming Pan ◽  
Ji Qing Song
Keyword(s):  
Water Absorbency ◽  
X Ray Diffraction ◽  
Ion Release ◽  
Hybrid Hydrogel ◽  
Potassium Release ◽  
Release Property ◽  
K Fertilizer ◽  
Aqueous Solution Polymerization ◽  
Xrd Patterns ◽  
Optimum Extraction

This study preliminarily evaluated water absorbency and potassium release property of a novel hybrid hydrogel material as a potential hydrogel K-fertilizer. This hybrid hydrogel material was prepared by introducing activated K-feldspar powder into starch-graft-PAA hydrogel networks via aqueous solution polymerization. The mineral phases were characterized by X-ray diffraction (XRD) patterns and the water absorbencies of the hybrid hydrogel along with potassium release property were preliminarily studied. The results indicate that the optimum extraction rate of potassium is 92.14% using the additive of NaCl at 950°C and 2h. The hydrogel was prepared at the amount of starch, cross-linker, initiator, and neutralization degree were 20%, 0.04%, 0.6%, and 80%, respectively. The hybrid hydrogel was synthesized by mixing hydrogel with activated powders. The results show the water absorbency of the hybrid hydrogel is 169g/g and the potassium ion release percentage is 8.0% of activated powder per gram.

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

Materials ◽  
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.

Efficient adsorption of chlorpyrifos onto modified activated carbon by gamma irradiation; a plausible adsorption mechanism

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky
Keyword(s):  
Gamma Irradiation ◽  
Area Measurement ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Pseudo First Order ◽  
Kinetics Of

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.

scholarly journals Insights into Starch Coated Nanozero Valent Iron-Graphene Composite for Cr(VI) Removal from Aqueous Medium

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Prasanna Kumarathilaka ◽  
Vimukthi Jayaweera ◽  
Hasintha Wijesekara ◽  
I. R. M. Kottegoda ◽  
S. R. D. Rosa ◽  
...  
Keyword(s):  
Point Of Zero Charge ◽  
Inert Material ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
X Ray Diffraction ◽  
Graphene Composite ◽  
Removal Capacity ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
First Time

Embedding nanoparticles into an inert material like graphene is a viable option since hybrid materials are more capable than those based on pure nanoparticulates for the removal of toxic pollutants. This study reports for the first time on Cr(VI) removal capacity of novel starch stabilized nanozero valent iron-graphene composite (NZVI-Gn) under different pHs, contact time, and initial concentrations. Starch coated NZVI-Gn composite was developed through borohydrate reduction method. The structure and surface of the composite were characterized by scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), and point of zero charge (pHpzc). The surface area and pHpzc of NZVI-Gn composite were reported as 525 m2 g−1 and 8.5, respectively. Highest Cr(VI) removal was achieved at pH 3, whereas 67.3% was removed within first few minutes and reached its equilibrium within 20 min obeying pseudo-second-order kinetic model, suggesting chemisorption as the rate limiting process. The partitioning of Cr(VI) at equilibrium is perfectly matched with Langmuir isotherm and maximum adsorption capacity of the NZVI-Gn composite is 143.28 mg g−1. Overall, these findings indicated that NZVI-Gn composite could be utilized as an efficient and magnetically separable adsorbent for removal of Cr(VI).

Removal of Heavy Metals from Aqueous Solution by Hydroxyapatite/Chitosan Composite

2013 ◽  
Vol 789 ◽  
pp. 176-179 ◽  
Author(s):  
Eny Kusrini ◽  
Nofrijon Sofyan ◽  
Dwi Marta Nurjaya ◽  
Santoso Santoso ◽  
Dewi Tristantini
Keyword(s):  
Heavy Metals ◽  
Aqueous Solution ◽  
Metal Ions ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Removal Of Heavy Metals ◽  
Sem Micrograph ◽  
Pseudo Second Order ◽  
Chitosan Composite

Hydroxyapatite/chitosan (HApC) composite has been prepared by precipitation method and used for removal of heavy metals (Cr6+, Zn2+and Cd2+) from aqueous solution. The HAp and 3H7C composite with HAp:chitosan ratio of 3:7 (wt%) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy-energy dispersive X-ray spectroscopy. The SEM results showed that HAp is spherical-shaped and crystalline, while chitosan has a flat structure. SEM micrograph of 3H7C composite reveals crystalline of HAp uniformly spread over the surface of chitosan. The crystal structure of HAp is maintained in 3H7C composite. Chitosan affects the adsorption capacity of HAp for heavy metal ions; it binds the metal ions as well as HAp. The kinetic data was best described by the pseudo-second order. Surface adsorption and intraparticle diffusion take place in the mechanism of adsorption process. The binding of HAp powder with chitosan made the capability of composite to removal of Cr6+, Zn2+and Cd2+from aqueous solution effective. The order of removal efficiency (Cr6+> Cd2+> Zn2+) was observed.

Behaviours of direct yellow 12 adsorption on mesoporous carbons with different pore geometries

2018 ◽  
Vol 2017 (1) ◽  
pp. 219-228
Author(s):  
Fengling Liu ◽  
Ziyan Guo ◽  
Hui Qiu ◽  
Xia Lu ◽  
Hua Fang ◽  
...  
Keyword(s):  
Mesoporous Carbons ◽  
X Ray Diffraction ◽  
Pore Characteristics ◽  
X Ray ◽  
Transmission Electron ◽  
Cylindrical Pores ◽  
Pseudo Second Order ◽  
Hexagonally Ordered ◽  
Adsorption Desorption ◽  
Interconnected Pore

Abstract Four kinds of mesoporous carbons, C1-h-w, C2-h-h, C3-s-w, and C4-s-h, with different pore geometries were prepared and characterised, and their adsorption behaviours with aqueous direct yellow 12 (DY-12) were investigated. The results of X-ray diffraction and transmission electron microscopy show that C1-h-w and C3-s-w have wormlike pore characteristics, whereas C2-h-h and C4-s-h have 2-D hexagonally arranged pores. According to the N2 adsorption/desorption results, the specific surface area of C1-h-w (1,378 m2/g) is the largest among the four carbons. The adsorption isotherms could be effectively fitted using the Langmuir model. The maximum adsorption amounts of C1-h-w, C2-h-h, C3-s-w and C4-s-h are 0.968 mmol/g, 0.726 mmol/g, 0.161 mmol/g and 0.156 mmol/g, respectively. The pseudo-second-order rate constants of C1-h-w (39.8 g/(mmol·min)) and C2-h-h (7.28 g/(mmol·min)) are substantially larger than those of C3-s-w (0.0046 g/(mmol·min)) and C4-s-h (0.014 g/(mmol·min)), indicating that an open and interconnected pore geometry is favourable for DY-12 adsorption. Furthermore, DY-12 diffusion in 2-D hexagonally ordered cylindrical pores is superior to that in wormlike pores due to the smoothness of the channels in the former. External mass transfer and intraparticle diffusion both play roles in the adsorption process.

Effect of Coating Bath Parameters on Properties of Electroless Nickel-Boron Alloy Coatings

2022 ◽  
Vol 10 (1) ◽  
pp. 0-0
Keyword(s):  
Surface Roughness ◽  
Surface Hardness ◽  
Chloride Concentration ◽  
Electroless Nickel ◽  
Nickel Chloride ◽  
Scratch Test ◽  
X Ray Diffraction ◽  
Tribological Behaviour ◽  
Pin On Disc ◽  
Mechanical Behaviours

Electroless nickel-boron binary coatings were obtained with various bath compositions to investigate the effect of bath parameters on tribological and mechanical behaviours of the coating. Characterisation of the coating for surface morphology and phase structure is done using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), respectively, whereas tribological behaviour of coatings is evaluated on a pin-on-disc tribo-tester. Elastic modulus and surface hardness of coatings have been obtained using nano-indentation technique, while the scratch behaviour of the coatings has been determined using micro-scratch test. Corrosion resistance of coatings is also determined. It is observed that surface roughness of the coatings increased with increase in sodium borohydride concentration but decreased slightly with increase in nickel chloride concentration. Friction and wear characteristics are found to increase with surface roughness which occurs due to increased boron content. Surface hardness and scratch hardness are also seen to vary with coating bath parameters.

scholarly journals Intercalation of oxalate ions in the interlayer space of a layered double hydroxide for nickel ions adsorption

2016 ◽  
Vol 5 (2) ◽  
pp. 144
Author(s):  
Doungmo Giscard ◽  
Théophile Kamgaing ◽  
Ranil Clément Tonleu Temgoua ◽  
Ervice Ymele ◽  
Francis Merlin Melataguia Tchieno ◽  
...  
Keyword(s):  
Interlayer Space ◽  
X Ray Diffraction ◽  
Batch Mode ◽  
Nickel Ions ◽  
X Ray ◽  
Modified Clay ◽  
Pseudo Second Order ◽  
Oxalate Ions ◽  
Double Hydroxide ◽  
Clay Materials

In this study, sorption properties of a synthesized anionic clay were enhanced by the intercalation of oxalate ions in its interlayer space. The pristine and modified clay materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and thermal analysis. These techniques confirmed the presence of oxalate ions in the interlayer space of the clay. The intercalated clay was then used as a matrix for the sorption in batch mode of nickel ions in aqueous solution. The influence of a number of parameters such as contact time, pH, initial concentration of the analyte and adsorbent dosage were studied. The maximum adsorption of nickel was obtained at pH 6, that is, about 90% Ni2+ removal. The adsorbent/adsorbate equilibrium follows a pseudo-second order kinetics and best matches the Langmuir model. The modified clay was shown to be efficient matrix for the sorption of nickel ions.

scholarly journals Natural and Modified Clays for the Removal of Cationic Dye from Water

2020 ◽  
Vol 24 (1) ◽  
pp. 562-579
Author(s):  
Asma Behilil ◽  
Driss Lancene ◽  
Brahim Zahraoui ◽  
Meriem Belhachemi ◽  
Houcine Benmehdi ◽  
...  
Keyword(s):  
Low Cost ◽  
Scientific Work ◽  
Exchange Capacity ◽  
Cationic Dye ◽  
X Ray Diffraction ◽  
Treatment Processes ◽  
Bet Analysis ◽  
Cost Treatment ◽  
Pseudo Second Order ◽  
Bet Theory

Abstract Research and scientific work continue to develop low-cost treatment processes in terms of improving water quality and environmental protection. Oxide of zinc supported in natural clay is synthesized by impregnated method. The role of this modification is to increase the adsorption capacity of a basic dye (Methylene Blue) compared with calcined and natural clays. These samples are characterized by several analytical methods, X-Ray Diffraction (XRD), Thermogravimetric Analysis/Differential Thermal Analysis (TGA/TDA) and Brunauer, Emmett and Teller (BET) theory. The results show that these clays contain three phases, Sericite 2M1, Clinochlore, quartz and the presence of a new phase for the modified clay named zincite. The measured cation exchange capacity (CEC) is 9 cmolc/kg and the BET analysis shows the increase of surface area for these clays, from 9 to 30 m2 g−1. The findings show also that the impregnated clay has a better affinity than others when the kinetics data were well fitted by the pseudo-second-order. The adsorption capacities calculated using Langmuir equation of MB onto natural, calcined and impregnated clays are 154.0, 139.6 and 158.1 mg/g, respectively. The thermodynamic data showed that the adsorption of MB on these samples were exothermic. From this study, it can be concluded that these clays are efficacious materials for cationic dye removal from wastewater.

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