Preparation of Ceramic Honeycomb Filter Supported Zeolite Membrane Modules by Microwave-Assisted In-Situ Crystallization

2006 ◽  
Vol 317-318 ◽  
pp. 697-700 ◽  
Author(s):  
C.D. Madhusoodana ◽  
Rathindra Nath Das ◽  
Yoshikazu Kameshima ◽  
Kiyoshi Okada
Keyword(s):  
Microwave Heating ◽  
Film Formation ◽  
Precursor Solution ◽  
Zeolite Membrane ◽  
Bet Surface Area ◽  
Microwave Assisted ◽  
In Situ Crystallization ◽  
Membrane Modules ◽  
Ceramic Honeycomb

Ceramic honeycomb filter supported zeolite membrane modules were prepared by a novel microwave-assisted in-situ crystallization method. The synthesis was done in two stages; microwave heating of substrates saturated with precursor solution to form a thin layer of zeolite nuclei (seeds) on the porous substrates followed by hydrothermal treatment to crystallize the ZSM-5 zeolite on the substrates. Zeolite formation was significantly enhanced by comparison with the conventional hydrothermal method, as evident from XRD and BET surface area results. The degree of film formation was varied with varying the dipping time of the substrates in the precursor solution prior to microwave heating, thereby controlling film formation inside the pores of the substrates. This new method of seeding using a simple domestic microwave oven was employed to zeolite membrane modules by forming a zeolite film on the thin walls of a honeycomb filter. The permeability of single gases and the separation of mixed gases were evaluated, showing a low pressure-drop and high permeating flux of light molecule gases.

FAU-type zeolite membranes synthesized by microwave assisted in situ crystallization

2008 ◽  
Vol 62 (28) ◽  
pp. 4357-4359 ◽  
Author(s):  
Guangqi Zhu ◽  
Yanshuo Li ◽  
Han Zhou ◽  
Jie Liu ◽  
Weishen Yang
Keyword(s):  
Zeolite Membranes ◽  
Microwave Assisted ◽  
Type Zeolite ◽  
In Situ Crystallization

Efficient, microwave-assisted intramolecular 1,3-dipolar cycloadditions of oximes and N-methylnitrones derived from o-alkenylmethoxy-acetophenones

2005 ◽  
Vol 83 (3) ◽  
pp. 260-265 ◽  
Author(s):  
Surinderjit Singh ◽  
M PS Ishar ◽  
Gajendra Singh ◽  
Rajinder Singh
Keyword(s):  
Microwave Irradiation ◽  
Microwave Heating ◽  
Reaction Times ◽  
Solvent Free ◽  
Dipolar Cycloadditions ◽  
Microwave Assisted ◽  
Solvent Free Conditions ◽  
A Minor ◽  
Acetophenone Oxime

Contrary to literature reports, the o-allyloxy- and crotyloxy-acetophenone-oximes (2a, 2b) are transformed to nitrones, which undergo regio- and stereoselective intramolecular 1,3-dipolar cycloadditions, both on microwave heating under solvent free conditions and refluxing in toluene, to afford novel cycloadducts (5a, 5b); the oxazepine-N-oxide (3a) reported to be formed in 98% yield was obtained only as a minor product (~10%). However, o-cinnamyloxy-acetophenone-oxime (2c) under similar conditions undergoes intramolecular N-alkylation to afford nitrone (3c). The reactions carried out under microwave irradiation are cleaner, require shorter reaction times, and have higher yields. Corresponding intramolecular 1,3-dipolar cycloadditions of N-methylnitrones (B), generated in situ from o-alkenylmethoxy-acetophenones (1a–1c) and N-methylhydroxylamine under solvent-free microwave irradiation conditions, are completely regio- and stereoselective, require much shorter reaction times, and afford adducts (4a–4c) in higher yields, as compared with their thermal counterparts.Key words: cycloadditions, nitrones, oximes, o-alkenylmethoxy-acetophenones, microwave, isoxazolidines.

scholarly journals PREPARATION OF ANTIMICROBIAL PAPER BY MICROWAVE-ASSISTED TWO-POT IN-SITU DEPOSITION OF ZINC OXIDE ON FILTER PAPER

2021 ◽  
Vol 55 (5-6) ◽  
pp. 681-688
Author(s):  
GENNE PATT O. SAMAR ◽  
ALVIN KARLO G. TAPIA ◽  
CHRYSLINE MARGUS N. PIÑOL ◽  
NACITA B. LANTICAN ◽  
MA. LOURDES F. DEL MUNDO ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Filter Paper ◽  
Antimicrobial Properties ◽  
Precursor Solution ◽  
Microwave Treatment ◽  
X Ray Diffraction ◽  
Bacterial Populations ◽  
Microwave Assisted ◽  
In Situ Deposition

We employed a microwave-assisted two-pot in-situ deposition technique to incorporate zinc oxide particulates in the structure of filter paper to produce antimicrobial paper. The process involved successive immersion of filter paper samples in ZnSO4 (precursor solution) and NaOH (precipitating agent) to form Zn(OH)2, which transformed into ZnO during microwave treatment. Successful deposition of ZnO particles on the filter paper was confirmed via X-ray diffraction and the corresponding morphologies were observed using field emission scanning electron microscopy. The ZnO-deposited papers were tested for antimicrobial activity and were found to be more effective against Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). Bacterial populations were reduced by up to 92 ± 2% and 57 ± 4% for S. aureus and E. coli, respectively. Also, it was found that the samples prepared using higher concentrations of ZnSO4 and NaOH exhibited better antimicrobial properties.

scholarly journals Microwave-assisted synthesis and enhanced photocatalytic performance of Bi2O2CO3 nanoplates

2021 ◽  
Author(s):  
Nitjawan Plubphon ◽  
Somchai Thongtem ◽  
Anukorn Phuruangrat ◽  
Chamnan Randorn ◽  
Titipun Thongtem
Keyword(s):  
Electron Microscopy ◽  
Microwave Heating ◽  
Photocatalytic Performance ◽  
Irradiation Time ◽  
Heating Power ◽  
Bet Surface Area ◽  
Microwave Assisted Synthesis ◽  
Internal Electric Field ◽  
Microwave Assisted ◽  
Environmental Treatment

Abstract In this research, Bi2O2CO3 (BOC) nanoplates as a semiconductor-based photocatalyst composed of [Bi2O2]2+ configuration layers were used for environmental treatment. Highly crystalline and pure phase of BOC nanoplates were successfully synthesized by a microwave-assisted method. Effect of irradiation time and microwave heating power on phase, purity, crystallinity, particle size and morphology of the as-synthesized products was investigated. The as-synthesized BOC nanoplates were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS) spectroscopy, Brunauer-Emmett-Teller (BET) surface area analysis, photoluminescence (PL) spectroscopy and UV-visible spectroscopy. Upon increasing microwave heating power, purity and crystallinity of the as-synthesized products were improved. Due to the existence of double internal electric field, the separation of photo-induced charged carriers was enhanced, leading to promote photocatalytic activity of the BOC nanoplates in degrading of methyl orange (MO) under UV radiation. The highest photocatalytic performance was achieved by using the BOC nanoplates synthesized by 600 W microwave for 60 min. A formation mechanism of BOC nanoplates was also proposed and discussed according to the experimental results.

Microwave assisted in situ decoration of a g-C3N4 surface with CdCO3 nanoparticles for visible light driven photocatalysis

2018 ◽  
Vol 42 (8) ◽  
pp. 6322-6331 ◽  
Author(s):  
Devthade Vidyasagar ◽  
Sachin G. Ghugal ◽  
Aditi Kulkarni ◽  
Ashok G. Shende ◽  
Suresh S. Umare ◽  
...  
Keyword(s):  
Visible Light ◽  
Microwave Heating ◽  
Carbon Nitride ◽  
Graphitic Carbon Nitride ◽  
Heating Method ◽  
Inorganic Hybrid ◽  
Microwave Assisted ◽  
Cadmium Carbonate ◽  
Visible Light Driven

Graphitic carbon nitride (g-C3N4) supported cadmium carbonate (CdCO3) as an organic–inorganic hybrid nanophotocatalyst was realised by an in situ microwave heating method.

scholarly journals Mesoporous Silica-Supported Sulfonyldiamine Ligand for Microwave-Assisted Transfer Hydrogenation

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Shaheen M. Sarkar ◽  
Md. Eaqub Ali ◽  
Md. Shaharul Islam ◽  
Md. Lutfor Rahman ◽  
S. S. Rashid ◽  
...  
Keyword(s):  
Microwave Heating ◽  
Significant Loss ◽  
Transfer Hydrogenation ◽  
High Catalytic Activity ◽  
Efficient Catalyst ◽  
Microwave Assisted ◽  
Ru Complex ◽  
Simple Filtration ◽  
Diamine Ligands

N-Sulfonyl-1,2-diamine ligands, derived from 1,2-diaminocyclohexane and 1,2-diaminopropane, were immobilized onto mesoporous SBA-15 silica. The SBA-15-supported sulfonyldiamine-Ru complex was preparedin situunder microwave heating at 60 W for 3 min. The prepared sulfonyldiamine-Ru complex was used as an efficient catalyst for the transfer hydrogenation of ketones to the corresponding secondary alcohols. The heterogeneous complex showed extremely high catalytic activity with 99% conversion rate under microwave heating condition. The complexes were regenerated by simple filtration and reused two times without significant loss of activity.

The Preparation and Characterization of Zeolite LTA Membrane with Microwave-Assisted Method

2014 ◽  
Vol 809-810 ◽  
pp. 682-688
Author(s):  
Li Xia Long ◽  
Hui Ling Du ◽  
Qun Li An ◽  
Xiang Shi ◽  
Jun Liu
Keyword(s):  
Secondary Growth ◽  
Precursor Solution ◽  
Zeolite Membrane ◽  
Molar Ratio ◽  
Microwave Assisted ◽  
Growth Method ◽  
Type Zeolite ◽  
Zeolite Seeds ◽  
Zeolite Lta ◽  
Controllable Process

A facial method to prepare zeolite LTA membrane via microwave-assisted heating method was reported. The A-type zeolite seeds were prepared by hydrothermal method from a precursor solution composed of A2O3:SiO2:Na2O:H2O with molar ratio of 1:5:40:1000. The optimized process parameters for synthesizing the zeolite seeds are reaction for 10 min, microwave power of 135 W, and the ratio of H2O/Na2O is 25. Zeolite LTA membrane was prepared via secondary growth method by microwave heating on the silicane and zeolite seed modified ceramic supports. The prepared zeolite seeds and membrane were characterized with X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) and scanning electron microscopy (SEM). The results show that the size of the zeolite seeds are in the range of 100-400 nm with regular cubic morphology, and the zeolite membrane have homogeneous thickness of 1.5 μm and perfect morphology without defects and pinholes. The easy operation and controllable process make the zeolite membrane by this method properly have wide application for the gas sensor and devices.

Functional Poly(p-Xylylene)s via Chemical Reduction of Poly(p-Phenylene Vinylene)s

2019 ◽  
Author(s):  
Ain Uddin ◽  
Weifan Sang ◽  
Yong Gao ◽  
Kyle Plunkett
Keyword(s):  
Film Formation ◽  
Chemical Reduction ◽  
Water Soluble ◽  
Phenylene Vinylene ◽  
Polymer Modification ◽  
Polymer Backbone ◽  
Crosslinking Process ◽  
Conducting Membranes ◽  
In Situ Crosslinking

The synthesis of poly(p-xylylene)s (PPXs) with sidechains containing alkyl bromide functionality, and their post-polymer modification, is described. The PPXs were prepared by a diimide hydrogenation of poly(p-phenylene vinylene)s (PPVs) that were originally synthesized by a Gilch polymerization. The polymer backbone reduction was carried out with hydrazine hydrate in toluene at 80 °C to provide polymers with the sidechain-containing bromide functionality intact. To demonstrate post-polymer modification of the sidechains, the resulting PPX polymers were modified with trimethylamine to form tetraalkylammonium ion functionality and were evaluated as anion conducting membranes. While PPX homopolymers containing tetralkylammonium ions were completely water soluble and not able to form valuable films, PPX copolymers containing mixed tetraalkylammonium ions and hydrophobic chains were capable of film formation and alkaline stability. In addition, an in situ crosslinking process that used N,N,N',N'-tetramethyl-1,6-hexanediamine during the tetraalkylammonium formation of brominated PPX polymers was also evaluated and gave reasonable films with conductivities of ~10 mS-cm-1.

Functional Poly(p-Xylylene)s via Chemical Reduction of Poly(p-Phenylene Vinylene)s

2019 ◽  
Author(s):  
Ain Uddin ◽  
Weifan Sang ◽  
Yong Gao ◽  
Kyle Plunkett
Keyword(s):  
Film Formation ◽  
Chemical Reduction ◽  
Water Soluble ◽  
Phenylene Vinylene ◽  
Polymer Modification ◽  
Polymer Backbone ◽  
Crosslinking Process ◽  
Conducting Membranes ◽  
In Situ Crosslinking

The synthesis of poly(p-xylylene)s (PPXs) with sidechains containing alkyl bromide functionality, and their post-polymer modification, is described. The PPXs were prepared by a diimide hydrogenation of poly(p-phenylene vinylene)s (PPVs) that were originally synthesized by a Gilch polymerization. The polymer backbone reduction was carried out with hydrazine hydrate in toluene at 80 °C to provide polymers with the sidechain-containing bromide functionality intact. To demonstrate post-polymer modification of the sidechains, the resulting PPX polymers were modified with trimethylamine to form tetraalkylammonium ion functionality and were evaluated as anion conducting membranes. While PPX homopolymers containing tetralkylammonium ions were completely water soluble and not able to form valuable films, PPX copolymers containing mixed tetraalkylammonium ions and hydrophobic chains were capable of film formation and alkaline stability. In addition, an in situ crosslinking process that used N,N,N',N'-tetramethyl-1,6-hexanediamine during the tetraalkylammonium formation of brominated PPX polymers was also evaluated and gave reasonable films with conductivities of ~10 mS-cm-1.

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