Synthesis of P(AA-AM)/ Organic Montmorillonite Super Absorbent Resin under Focused Signal-Mode Microwave Irradiation

2013 ◽  
Vol 746 ◽  
pp. 137-141
Author(s):  
Shui Li Lai ◽  
Ying Hua Gao
Keyword(s):  
Microwave Irradiation ◽  
Cetyltrimethylammonium Bromide ◽  
Irradiation Time ◽  
Single Mode ◽  
Synthesis System ◽  
Organic Montmorillonite ◽  
Irradiation Power ◽  
Aqueous Solution Polymerization ◽  
Signal Mode ◽  
Irradiation Technology

A super absorbent resin (SAR) of acrylic acid (AA)/acrylamide (AM) /organic montmorillonite (OMMT) composite was synthesized by aqueous solution polymerization. This process was carried out under precision microwave organic synthesis system and its single-mode focusing microwave irradiation technology was studied. The montmorillonite (MMT) was modified by treating with cetyltrimethylammonium bromide. Moreover, the factors that effect on liquid absorbency rate of the SAR were discussed, such as neutralization degree (ND) of AA, microwave irradiation time, microwave irradiation power and the dosage of the OMMT. It gave the best liquid absorbency rate (1520g.g-1 and 165g.g-1 in purified water and 0.9wt% NaCl solution, respectively).

Preparation, Characterization of P(AA-AM)/Organic Montmorillonite Super Absorbent Resin under Focused Signal-Mode Microwave Irradiation

2013 ◽  
Vol 746 ◽  
pp. 142-146
Author(s):  
Shui Li Lai ◽  
Ying Hua Gao
Keyword(s):  
Microwave Irradiation ◽  
Single Mode ◽  
X Ray Diffraction ◽  
Synthesis System ◽  
Organic Montmorillonite ◽  
Modified Montmorillonite ◽  
Aqueous Solution Polymerization ◽  
Signal Mode ◽  
Irradiation Technology

A super absorbent resin (SAR) of acrylic acid (AA)/acrylamide (AM) /organic montmorillonite (OMMT) composite was synthesized by aqueous solution polymerization. This process was carried out under precision microwave organic synthesis system and its single-mode focusing microwave irradiation technology was studied. The montmorillonite (MMT) was modified by treating with cetyltrimethylammonium bromide.The characteristics of the obtained SAR, natural and modified montmorillonite were characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results show that the intercalation is successful, the CTAB as a organic modifier introuduced into lattice layers of montmorillonite by cation-exchange reaction.The SAR have higher liquid absorbency rate.

Preparation of Polymer Suppressant in Coal Transportation under Single Mode Microwave Irradiation

2012 ◽  
Vol 198-199 ◽  
pp. 19-22
Author(s):  
Shui Li Lai ◽  
Ying Hua Gao ◽  
Qiang Chai
Keyword(s):  
Acrylic Acid ◽  
Microwave Irradiation ◽  
Irradiation Time ◽  
Weight Ratio ◽  
Single Mode ◽  
Solution Polymerization ◽  
Oxidized Starch ◽  
Irradiation Power ◽  
Aqueous Solution Polymerization ◽  
Radiation Time

The aqueous solution polymerization of acrylic acid, acrylamide and oxidized starch under single mode microwave irradiation was studied, and a polymer suppressant was synthesized. The factors that influence on performance of the polymer suppressant were discussed, including microwave irradiation time, neutralization degree of acrylic acid (AA), the dosage of oxidized starch. The polymer suppressant was characterized by IR and scanning electron microscopy (SEM). Results indicated that the optimal synthetic conditions are as follows: microwave irradiation power, 300 W; radiation time, 2 mins; 50% neutralization degree of the AA; m(AA) : m(AM) : m(oxidized starch)= 5.0 : 3.3 : 3.4, weight ratio initiator in the feed is 0.4%, respectively.

Preparation, Characterization of Organo-Montmorillonite under Focused Signal-Mode Microwave Irradiation

2012 ◽  
Vol 198-199 ◽  
pp. 85-88
Author(s):  
Shui Li Lai ◽  
Ying Hua Gao
Keyword(s):  
Cation Exchange ◽  
Exchange Reaction ◽  
Cetyltrimethylammonium Bromide ◽  
Organic Modifier ◽  
X Ray Diffraction ◽  
Synthesis System ◽  
X Ray ◽  
Cation Exchange Reaction ◽  
Signal Mode

In this paper，the organo-montmorillonite (OMMT) was prepared by cation exchange reaction, using sodium montmorillonite (Na+-MMT) and cetyltrimethylammonium bromide(CTAB) as all intercalation agent under precision microwave organic synthesis system. The structure of the montmorillonite was characterized by X-ray diffraction (XRD)、infrared spectrum (IR)、thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results show that the intercalation is successful, the CTAB as a organic modifier introuduced into lattice layers of montmorillonite by cation-exchange reaction and the surface morphology of OMMT is complete exfoliation, the distance between the lattice layers of montmorillonite has been greatly increased.

scholarly journals Optimization of Vacuum Microwave-Mediated Extraction of Syringoside and Oleuropein from Twigs of Syringa oblata

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Xiangping Liu ◽  
Xuemin Jing ◽  
Guoliang Li
Keyword(s):  
Microwave Irradiation ◽  
Volume Fraction ◽  
Irradiation Time ◽  
Suitable Method ◽  
Optimal Parameters ◽  
Soaking Time ◽  
Solid Ratio ◽  
Vacuum Microwave ◽  
Irradiation Power ◽  
Conventional Methods

A vacuum microwave-mediated method was used to extract syringoside and oleuropein from Syringa oblata twigs. The optimal extraction conditions were an ethanol volume fraction of 40%, a liquid-solid ratio of 17 mL/g, 1 h of soaking time, −0.08 MPa of vacuum, a microwave irradiation power of 524 W, and a microwave irradiation time of 8 min. Under optimal parameters, the maximum yields of syringoside (5.92 ± 0.24 mg/g) and oleuropein (4.02 ± 0.18 mg/g) were obtained. The proposed method is more efficient than conventional methods for extracting syringoside and oleuropein from Syringa oblata. Moreover, less energy and time were required. The results implied that vacuum microwave-mediated extraction is a suitable method for the extraction of thermosensitive glycosides such as syringoside and oleuropein.

scholarly journals Effects of microwave irradiation on the moisture content of various wood chip fractions obtained from different tree species

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Monika Aniszewska ◽  
Krzysztof Słowiński ◽  
Ewa Tulska ◽  
Witold Zychowicz
Keyword(s):  
Moisture Content ◽  
Microwave Irradiation ◽  
Microwave Power ◽  
Irradiation Time ◽  
Initial Moisture Content ◽  
Radiant Energy ◽  
Wood Chip ◽  
Wood Chips ◽  
Chip Size ◽  
Drying Rates

AbstractThe paper proposes the use of microwave irradiation to lower the initial moisture content of wood chips. The study involved willow and fir chips fractionated by means of a sieve separator and unfractionated ash chips. The wood chips were exposed to a constant microwave power of 800 W for 30 s, 60 s, 120 s and 180 s. The chips were weighed before and after irradiation to measure loss of moisture. It was found that the decline in moisture content increased with wood chip size for a given irradiation time and microwave power. The initial moisture content of wood chips was not found to significantly affect loss of moisture as the drying rates of wood chips with higher and lower moisture content exposed to microwaves were not statistically different. The results showed that irradiation intensity increased with the time of exposure to microwaves and unit radiant energy per unit of evaporated moisture decreased with increasing wood chip size in the 3.15–31.50 mm range.

Optimization of biodiesel synthesis under simultaneous ultrasound-microwave irradiation using response surface methodology (RSM)

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Seyed Mohammad Safieddin Ardebili ◽  
Teymor Tavakoli Hashjin ◽  
Barat Ghobadian ◽  
Gholamhasan Najafi ◽  
Stefano Mantegna ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Microwave Irradiation ◽  
Response Surface ◽  
Palm Oil ◽  
Catalyst Concentration ◽  
Irradiation Time ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Biodiesel Synthesis

AbstractThis work investigates the effect of simultaneous ultrasound-microwave irradiation on palm oil transesterification and uncovers optimal operating conditions. Response surface methodology (RSM) has been used to analyze the influence of reaction conditions, including methanol/palm oil molar ratio, catalyst concentration, reaction temperature and irradiation time on biodiesel yield. RSM analyses indicate 136 s and 129 s as the optimal sonication and microwave irradiation times, respectively. Optimized parameters for full conversion (97.53%) are 1.09% catalyst concentration and a 7:3.1 methanol/oil molar ratio at 58.4°C. Simultaneous ultrasound-microwave irradiation dramatically accelerates the palm oil transesterification reaction. Pure biodiesel was obtained after only 2.2 min while the conventional method requires about 1 h.

scholarly journals Utilization of the microwave electric or magnetic field in the synthesis of monometallic and bimetallic nanoparticles

RSC Advances ◽  
2015 ◽  
Vol 5 (19) ◽  
pp. 14637-14645 ◽  
Author(s):  
Takuya Sumi ◽  
Ralf Dillert ◽  
Satoshi Horikoshi
Keyword(s):  
Magnetic Field ◽  
Microwave Irradiation ◽  
Bimetallic Nanoparticles ◽  
Single Mode ◽  
Microwave Resonator ◽  
Lower Temperature

On preparation of bimetal nanoparticles by using a single-mode microwave resonator, Ag–Ni and Pd–Ag nanocomposites were synthesized under microwave irradiation at 80 centigrade, which was a lower temperature than that for reduction of Ag ion.

scholarly journals Acrylic resin disinfection by peracetic acid and microwave energy

2015 ◽  
Vol 63 (3) ◽  
pp. 315-318 ◽  
Author(s):  
Carmen Beatriz Borges FORTES ◽  
Vicente Castelo Branco LEITUNE ◽  
Fabrício Mezzomo COLLARES ◽  
Nélio Bairros DORNELLES JUNIOR ◽  
Stéfani Becker RODRIGUES ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Microwave Irradiation ◽  
Incubation Period ◽  
Peracetic Acid ◽  
Acrylic Resin ◽  
Microwave Energy ◽  
The Other ◽  
Disinfection Methods ◽  
Acrylic Resins ◽  
Irradiation Power

Objective: The objective of this study was to evaluate the effectiveness of disinfection methods in microwave and immersion in peracetic acid in heat-cured, self-cured and microwave-cured acrylic resin, contaminated with Candida albicans. Methods: Five specimens were prepared for each type of acrylic resin. All were infected with Candida Albicans, incubated at 37°C for 24 hours. The group which underwent microwave energy was irradiated with a power of 840W for 1 minute and the other group underwent disinfection by soaking of 0.2% peracetic acid for 5 minutes. Results: All samples proved to be contaminated after the incubation period. After the different processes of disinfection, both immersion in 0.2% peracetic acid as microwave irradiation were effective in disinfection of the 3 types of acrylic resins contaminated by Candida Albicans. Conclusion: Concluded that soaking in 0,2% peracetic acid for 5 minutes with microwave irradiation power 840W for 1 minute are effective methods for disinfecting heat-cured acrylic resin, self-cured acrylic resin and microwave-cured acrylic resin, contaminated with Candida Albicans.

Demulsification of water-in-crude oil emulsions using single mode and multimode microwave irradiation

2017 ◽  
Vol 189 ◽  
pp. 347-356 ◽  
Author(s):  
Denisson Santos ◽  
Eloá C.L. da Rocha ◽  
Robson L.M. Santos ◽  
Aarón J. Cancelas ◽  
Elton Franceschi ◽  
...  
Keyword(s):  
Microwave Irradiation ◽  
Crude Oil ◽  
Single Mode ◽  
Oil Emulsions

Microwave-Irradiated Preparation of Super Absorbent Resin by Graft Copolymerization of Starch and Acrylic Acid

2011 ◽  
Vol 291-294 ◽  
pp. 1335-1338
Author(s):  
Da Biao Zhao
Keyword(s):  
Acrylic Acid ◽  
Microwave Irradiation ◽  
Graft Copolymerization ◽  
Irradiation Time ◽  
Low Cost ◽  
Power Level ◽  
Conventional Heating ◽  
Simple Process ◽  
One Step ◽  
Microwave Power Level

Graft copolymerization of acrylic acid(AA) on starch to prepare super absorbent resin (SAR) under microwave irradiation were investigated using N,N-methylene bis-acrylamide as crosslinker and potassium persulfate as initiator. The influences of the amount of initiator and crosslinker, neutralization degree of acrylic acid(AA), ratio of starch to AA, microwave power level and irradiation time on the distilled water absorption amount of resin were investigated. The results indicated that it only needed 4min under the microwave level of 231W to obtain the resin with the maximum absorption amount of 1110g×g-1, under the conditions that 0.3wt% initiator, 0.02wt% crosslinker, 60% neutralization degree of acrylic acid, the ratio of starch to acrylic acid of 0.25. Under microwave irradiation, the synthesis and drying of super absorbent resin could be completed at one step without nitrogen. Compared to conventional heating method, the methods had the striking advantages of short reaction time, simple process and low cost.

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