Flocculation of a High-Turbidity Kaolin Suspension Using Hydrophobic Modified Quaternary Ammonium Salt Polyacrylamide

In this work, a novel cationic polyacrylamide (PAMD) was synthesized by acrylamide (AM) diallyl dimethyl ammonium chloride (DMD) and dodecyl polyglucoside (DPL) under low-pressure ultraviolet (UV) initiation. The intrinsic viscosity and cationic degree of PAMD were optimized in copolymerization. The optimum synthesis conditions that affect polymerization were determined to be solid content 30%, DPL content 25%, DMD content 30%, illumination time 135 min, and pH 9. The flocculation performance of flocculant PAMD with a high cationic degree was investigated in the purification of high-turbidity water. The flocculation mechanism was correspondingly studied and summarized based on Fourier transform-infrared (FTIR) analysis. Finally, the results of an experimental simulation using the response surface method show that 98.9% supernatant transmittance was achieved under dosage 4 mg/L, fast stirring time 20 min, pH 7, and stirring speed 320 rpm.

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Synthesis, Analysis, and Testing of BiOBr-Bi2WO6Photocatalytic Heterojunction Semiconductors

International Journal of Photoenergy ◽

10.1155/2015/630476 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 21

Author(s):

Xiangchao Meng ◽

Zisheng Zhang

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Degradation Process ◽

Light Irradiation ◽

Enhancement Effect ◽

Electron Hole ◽

Experimental Conditions ◽

Synthesis Conditions ◽

Optimum Synthesis ◽

Photocatalytic Activities

In photocatalysis, the recombination of electron-hole pairs is generally regarded as one of its most serious drawbacks. The synthesis of various composites with heterojunction structures has increasingly shed light on preventing this recombination. In this work, a BiOBr-Bi2WO6photocatalytic heterojunction semiconductor was synthesized by the facile hydrothermal method and applied in the photocatalytic degradation process. It was determined that both reaction time and temperature significantly affected the crystal structure and morphologies of the photocatalysts. BiOBr (50 at%)-Bi2WO6composites were prepared under optimum synthesis conditions (120°C for 6 h) and by theoretically analyzing the DRS results, it was determined that they possessed the suitable band gap (2.61 eV) to be stimulated by visible-light irradiation. The photocatalytic activities of the as-prepared photocatalysts were evaluated by the degradation ofRhodamine B (RhB)under visible-light irradiation. The experimental conditions, including initial concentration, pH, and catalyst dosage, were explored and the photocatalysts in this system were proven stable enough to be reused for several runs. Moreover, the interpreted mechanism of the heterojunction enhancement effect proved that the synthesis of a heterojunction structure provided an effective method to decrease the recombination rate of the electron-hole pairs, thereby improving the photocatalytic activity.

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Synthesis and Application of Glyoxalted Polyacrylamide Paper Strengthening Agent

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1385 ◽

2011 ◽

Vol 236-238 ◽

pp. 1385-1390 ◽

Cited By ~ 3

Author(s):

Zhao Yang Yuan ◽

Hui Ren Hu ◽

Yang Bing Wen

Keyword(s):

Ph Value ◽

Raw Materials ◽

Strength Properties ◽

Synthesis Conditions ◽

Paper Making ◽

H Nmr ◽

Dimethyl Ammonium ◽

Ft Ir ◽

Radical Solution ◽

Diallyl Dimethyl Ammonium Chloride

The glyoxalted polyacrylamide(GPAM) resins were obtained by cross-linking reaction between glyoxal and cationic polyacrylamide(CPAM) through aqueous solution copolymerization. The based CPAM was synthesized with acrylamide(AM) and diallyl dimethyl ammonium chloride(DADMAC) as raw materials by living free radical solution polymerization. Various synthesis conditions were discussed and the optimum conditions for copolymer’s synthesis were as follows: the amount of DADMAC 20%(wt), the charge of the initiator 0.5%(wt), the dosage of chain transfer agent(2-mercaptoethanol) 1.0%(wt), and the charge of crosslinking monomer 9.0%, the dosage of glyoxal 25%(wt), the pH value of the tertiary reaction 7.5-8.0 and the tertiary temperature about 65°C. The structure of the resulting product was characterized by FT-IR, 1H-NMR. Then the GPAM resins were used in the process of paper-making as wet-end additive, the results showed that the paper sheets can get a significant increase in strength properties from the added novel product.

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Slurry Preparation Effects on the Cemented Phosphogypsum Backfill through an Orthogonal Experiment

Minerals ◽

10.3390/min9010031 ◽

2019 ◽

Vol 9 (1) ◽

pp. 31 ◽

Cited By ~ 6

Author(s):

Xibing Li ◽

Yanan Zhou ◽

Quanqi Zhu ◽

Shitong Zhou ◽

Chendi Min ◽

...

Keyword(s):

Orthogonal Experiment ◽

Dominant Role ◽

Solid Content ◽

Strength Development ◽

Range Analysis ◽

Setting Times ◽

Stirring Time ◽

Binder Ratio ◽

Four Levels ◽

Slurry Preparation

The cemented phosphogypsum (PG) backfill technique provides a new method for massive consumption of PG, and therefore alleviating the environmental pollution of PG. This study considered the effects of slurry preparation on the performance of cemented PG backfill. A L16(44) orthogonal experiment was designed to analyze four factors, namely the solid content, phosphogypsum-to-binder ratio (PG/B ratio), stirring time and stirring speed, with each factor having four levels. According to the range analysis, the solid content played the dominant role in controlling the bleeding rate, while the setting times strongly depended on the PG/B ratio. In terms of strength development of the backfill, the PG/B ratio was shown to be the most significant factor determining the unconfined compressive strength (UCS), followed by the solid content, stirring time and stirring speed. Furthermore, the results showed that the slurry preparation affected the environmental behavior of impurities that originated in PG. By analyzing the concentrations of impurities in the bleeding water of the slurry as well as the leachates of the tank leaching test, the results showed that the release of F− and SO42− was aggravated clearly with the increase in the PG/B ratio, while the release of PO43− always remained at relatively low levels.

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Green Synthesis and Characterization of High-Purity Monodispersed Cupric Oxide (CuO) Nanopowder

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.801.351 ◽

2019 ◽

Vol 801 ◽

pp. 351-356

Author(s):

Yuan Teng Foo ◽

Li Ting Foo ◽

Ladan Shahcheragh ◽

Bahman Amini Horri ◽

Babak Salamatinia

Keyword(s):

Green Synthesis ◽

High Purity ◽

Cupric Oxide ◽

Sol Gel ◽

Synthesis Method ◽

Ionic Exchange ◽

Synthesis Conditions ◽

Calcination Temperatures ◽

Optimum Synthesis ◽

Exchange Material

In this study, high quality monodispersed nanocrystalline cupric oxide (CuO) nanopowder was prepared through novel sol-gel green synthesis method, assisted by sodium alginate (Na-ALG) as the green ionic exchange material. The morphology and structural properties of CuO nanopowders synthesized with and without the incorporation of extrusion dripping, at different Na-ALG solution concentrations and calcination temperatures, were studied using thermalgravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and Raman spectroscopy. Optimum synthesis conditions were identified, resulting in high-purity, monodispersed nanocrystalline CuO powder in the range of 9.92 – 12.4 nm, which could have a promising future in various applications.

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Growth of Carbon Nanocoils Using Chemical Vapor Deposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.1851 ◽

2009 ◽

Vol 79-82 ◽

pp. 1851-1854

Author(s):

C.C. Su ◽

Y.L. Hsieh ◽

S.H. Chang

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Silicon Substrates ◽

Synthesis Conditions ◽

Optimum Synthesis ◽

Coil Geometry ◽

Vapor Deposition Technique ◽

Electro Magnetic ◽

Mechanical Sensing

We present the synthesis of carbon nanocoils using the chemical vapor deposition technique with metal catalysts on silicon substrates. The optimum synthesis conditions and coil geometry are summarized. The coils have distribution of the outside diameter of 300 nm to 1200 nm, wire diameter of 150 nm to 400 nm and the pitch of the coil of 150 nm to 1200 nm. Applications of the developed carbon nanocoils can be electro-mechanical sensing and the electro-magnetic insulation.

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Further Exploration of Sucrose-Citric Acid Adhesive: Synthesis and Application on Plywood

Polymers ◽

10.3390/polym11111875 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1875 ◽

Cited By ~ 15

Author(s):

Shijing Sun ◽

Zhongyuan Zhao ◽

Kenji Umemura

Keyword(s):

Citric Acid ◽

Research Direction ◽

Synthesis Temperature ◽

Solid Content ◽

National Standard ◽

Synthesis Process ◽

Synthesis Mechanism ◽

Synthesis Time ◽

Synthesis Conditions ◽

Bond Performance

The development of eco-friendly adhesives is a major research direction in the wood-based material industry. Previous research has already demonstrated the mixture of sucrose and citric acid could be utilized as an adhesive for the manufacture of particleboard. Herein, based on the chemical characteristics of sucrose, a synthesized sucrose-citric acid (SC) adhesive was prepared, featuring suitable viscosity and high solid content. The investigation of synthesis conditions on the bond performance showed that the optimal mass proportion between sucrose and citric acid was 25/75, the synthesis temperature was 100 °C, and the synthesis time was 2 h. The wet shear strength of the plywood bonded with SC adhesive, which was synthesized at optimal conditions and satisfied the China National Standard GB/T 9846-2015. The synthesis mechanism was studied by both 13C NMR analysis and HPLC, and the chemical composition manifesting caramelization reaction occurred during the synthesis process. The results of ATR FT-IR indicated the formation of a furan ring, carbonyl, and ether groups in the cured insoluble matter of the SC adhesive, which indicated dehydration condensation as the reaction mechanism between sucrose and citric acid.

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Synthesis Dependent Structural Magnetic and Electrical Properties of CR-Doped Lead-Free Multiferroic AlFeO3

Crystals ◽

10.3390/cryst10060440 ◽

2020 ◽

Vol 10 (6) ◽

pp. 440

Author(s):

Sharah Ali A. Aldulmani ◽

Imen Raies ◽

Mongi Amami ◽

Lamia Ben Farhat

Keyword(s):

Dielectric Response ◽

Oxygen Vacancies ◽

Complex Impedance ◽

Magnetic Ordering ◽

Dielectric Behavior ◽

Frequency Variation ◽

Synthesis Conditions ◽

Co Precipitation ◽

Conducting Species ◽

Method Show

Polycrystalline samples AlFe0.95Cr0.05O3 synthetized by a solid state (SR) and a co-precipitation (cop) method show an orthorhombic system in space group Pc21n. It was found that, the cation distribution and magnetic ordering vary toughly on the synthesis conditions. We deployed impedance spectroscopy in studying the dielectric behavior of AlFe0.95Cr0.05O3. The significant results of this work are: for both samples, permittivity and dielectric loss are very sensitive to the temperature and frequency variation. The existence of supplementary imperfections and conducting species in AFCr5-s ceramics led to important dielectric permittivity in AFCr5-s. Values of the activation energy determined at low temperature point toward oxygen vacancies motion in slight range, however at high temperature, such a motion turns to long-range one. The dielectric response in case of AFCr5-s was assigned throw complex impedance plots to the grain as well as grain boundary. Conversely, additional individual pores similarly participate to dielectric belongings of AFCr5-cop.

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REMOVAL OF DIQUATERNARY AMMONIUM CATIONS FROM AS-SYNTHESIZED SSZ-16 ZEOLITE

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2017.9.0026 ◽

2017 ◽

Vol 9 ◽

pp. 26 ◽

Cited By ~ 1

Author(s):

Tatana Supinkova ◽

Ivan Jirka ◽

Jan Drahokoupil ◽

Jan Langmaier ◽

Vlastimil Fila ◽

...

Keyword(s):

Chemical Technology ◽

Structure Directing Agent ◽

Phase Purity ◽

Synthesis Conditions ◽

Catalytic Transformations ◽

Optimum Synthesis ◽

Diquaternary Ammonium

Zeolites are stable microporous aluminosilicates with numerous applications in chemical technology such as separation of species and catalytic transformations. Our study is focused on a weakly explored zeolite SSZ-16 with pore constrictions defined by 8-membered oxygen rings. Key results are the preparation of Et6-diquat-5 dication used as a structure directing agent (SDA) and finding the optimum synthesis conditions with respect to zeolite phase purity. Stability of SDA was examined in conditions similar to those of autoclave synthesis (concentration, pH, temperature). Moreover, the content and location of SDA species in zeolite phase and conditions of SDA decomposition were investigated.

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Preparation and Application of a Novel Formaldehyde-Free Fixing Agent

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.713-715.2793 ◽

2015 ◽

Vol 713-715 ◽

pp. 2793-2797

Author(s):

Jian Ping Liu

Keyword(s):

Ammonium Chloride ◽

Sodium Sulfite ◽

Ammonium Persulfate ◽

Color Fastness ◽

Reactive Dyeing ◽

Synthesis Conditions ◽

Optimum Synthesis ◽

Initiation System ◽

Binary Polymer

Using diallylamine , hydrochloric and dimethyl diallyl ammonium chloride as reactants, ammonium persulfate / sodium sulfite as initiation system,binary polymer was prepared in water phase.The binary polymer was applied to cotton of reactive dyeing as a fixing agent,propreities of fixing fabric were tested.The results showed that the optimum synthesis conditions were as follows: 50 g of diallylamine, 600 g of 40% dimethyl diallyl ammonium chloride,6 g of ammonium persulfate, dropping of initiation at 80°C for 3 h.The reactive dyeings after binary polymer treatment had fairly good color fastness with 4-5 grade to dry rubbing,4 grade to wet rubbing, color fastness with good to soaking and formaldehyde-free.

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Fe/SiO2 Nanocomposite Soft Magnetic Materials

MRS Proceedings ◽

10.1557/proc-703-v6.3 ◽

2001 ◽

Vol 703 ◽

Cited By ~ 2

Author(s):

S. Hui ◽

Y. D. Zhang ◽

T. D. Xiao ◽

Mingzhong Wu ◽

Shihui Ge ◽

...

Keyword(s):

Particle Size ◽

Magnetic Materials ◽

Annealing Temperature ◽

Magnetic Measurements ◽

Soft Magnetic Materials ◽

Crystallographic Structure ◽

Ferromagnetic Behavior ◽

Soft Magnetic ◽

Synthesis Conditions ◽

Optimum Synthesis

ABSTRACTIn an effort to explore new highly resistive soft magnetic materials, Fe/SiO2 nanocomposite materials have been synthesized using a wet chemical reaction approach in which the precursor complex was annealed at various temperatures. The crystallographic structure, nanostructure, morphology, and magnetic properties of the synthetic Fe/SiO2 particles were studied by x-ray diffraction, transmission electron microscopy, and magnetic measurements. The experimental results show that for this approach, the [.alpha]-Fe particles are coated with amorphous silica. The progress of the reaction, the purity of Fe/SiO2 in the synthetic powder, and the Fe particle size are highly dependent on the annealing temperature. By adjusting the annealing temperature, the particle size can be controlled from approximately 20 nm to 70 nm. For the synthetic nanopowder obtained by H2 reduction at 400 °C, there exists a superparamagnetic behavior below room temperature; while for the nanopowders obtained by reduction at higher temperatures, the ferromagnetic behavior is dominant. Based on these studies, optimum synthesis conditions for Fe/SiO2 nanocomposites is determined.

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