Synthesis of inorganic doped polyvinyl alcohol/hydroxypropyl methyl cellulose mixed matrix membrane for pervaporative separation of dimethyl carbonate/methanol mixtures

2020 ◽  
Vol 37 (4) ◽  
pp. 698-706
Author(s):  
Derya Unlu
2015 ◽  
Vol 42 (6) ◽  
pp. 5309-5328 ◽  
Author(s):  
Bahareh Baheri ◽  
Raziyeh Ghahremani ◽  
Mohammad Peydayesh ◽  
Mahnaz Shahverdi ◽  
Toraj Mohammadi

RSC Advances ◽  
2018 ◽  
Vol 8 (37) ◽  
pp. 20669-20678 ◽  
Author(s):  
YongSung Kwon ◽  
Shivshankar Chaudhari ◽  
ChaEun Kim ◽  
DaHae Son ◽  
JiHwan Park ◽  
...  

Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture.


2020 ◽  
Vol 137 (42) ◽  
pp. 49308
Author(s):  
Zhanbin Wang ◽  
Jiahao Liu ◽  
Houchao Shan ◽  
Guozhen Li ◽  
Ze Wang ◽  
...  

2021 ◽  
Vol 13 (9) ◽  
pp. 11296-11305
Author(s):  
Xu Jiang ◽  
Shanshan He ◽  
Gang Han ◽  
Jun Long ◽  
Songwei Li ◽  
...  

Author(s):  
Amita Bedar ◽  
Beena G. Singh ◽  
Pradip K. Tewari ◽  
Ramesh C. Bindal ◽  
Soumitra Kar

Abstract Cerium oxide (ceria) contains two stable states of cerium ions (Ce3+ and Ce4+). The presence of these two states and the ability to swap from one state to another (Ce3+ ↔ Ce4+) by scavenging the highly reactive oxygen species (ROS) generated from radiolysis of water, ensure the enhanced stability of polysulfone (Psf) membranes in the γ-radiation environment. In this study, the ROS scavenging ability of ceria was studied. Ceria nanoparticles were found to scavenge ROS like hydroxyl radicals and hydrogen peroxide (H2O2). The H2O2 scavenging is due to the peroxidase-like catalytic activity of ceria nanoparticles. The ROS scavenging is responsible for offering protection to the Psf host matrix and in turn the stability to the Psf-ceria mixed-matrix membranes (MMMs) in γ-radiation environment. Thus, presence of ceria nanoparticles provides an opportunity for utilizing Psf-ceria MMMs in ionizing radiation environment with increased life span, without compromise in the performance.


Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 194
Author(s):  
Xiuxiu Ren ◽  
Masakoto Kanezashi ◽  
Meng Guo ◽  
Rong Xu ◽  
Jing Zhong ◽  
...  

A new polyhedral oligomeric silsesquioxane (POSS) designed with eight –(CH2)3–NH–(CH2)2–NH2 groups (PNEN) at its apexes was used as nanocomposite uploading into 1,2-bis(triethoxysilyl)ethane (BTESE)-derived organosilica to prepare mixed matrix membranes (MMMs) for gas separation. The mixtures of BTESE-PNEN were uniform with particle size of around 31 nm, which is larger than that of pure BTESE sols. The characterization of thermogravimetric (TG) and gas permeance indicates good thermal stability. A similar amine-contained material of 3-aminopropyltriethoxysilane (APTES) was doped into BTESE to prepare hybrid membranes through a copolymerized strategy as comparison. The pore size of the BTESE-PNEN membrane evaluated through a modified gas-translation model was larger than that of the BTESE-APTES hybrid membrane at the same concentration of additions, which resulted in different separation performance. The low values of Ep(CO2)-Ep(N2) and Ep(N2) for the BTESE-PNEN membrane at a low concentration of PNEN were close to those of copolymerized BTESE-APTES-related hybrid membranes, which illustrates a potential CO2 separation performance by using a mixed matrix membrane strategy with multiple amine POSS as particles.


2021 ◽  
Vol 22 (5) ◽  
pp. 2682
Author(s):  
Nazim Nassar ◽  
Felicity Whitehead ◽  
Taghrid Istivan ◽  
Robert Shanks ◽  
Stefan Kasapis

Crosslinking of hydroxypropyl methyl cellulose (HPMC) and acrylic acid (AAc) was carried out at various compositions to develop a high-solid matrix with variable glass transition properties. The matrix was synthesized by the copolymerisation of two monomers, AAc and N,N′-methylenebisacrylamide (MBA) and their grafting onto HMPC. Potassium persulfate (K2S2O8) was used to initiate the free radical polymerization reaction and tetramethylethylenediamine (TEMED) to accelerate radical polymerisation. Structural properties of the network were investigated with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), modulated differential scanning calorimetry (MDSC), small-deformation dynamic oscillation in-shear, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results show the formation of a cohesive macromolecular entity that is highly amorphous. There is a considerable manipulation of the rheological and calorimetric glass transition temperatures as a function of the amount of added acrylic acid, which is followed upon heating by an extensive rubbery plateau. Complementary TGA work demonstrates that the initial composition of all the HPMC-AAc networks is maintained up to 200 °C, an outcome that bodes well for applications of targeted bioactive compound delivery.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2053
Author(s):  
Dragutin Nedeljkovic

An increased demand for energy in recent decades has caused an increase in the emissions of combustion products, among which carbon-dioxide is the most harmful. As carbon-dioxide induces negative environmental effects, like global warming and the greenhouse effect, a decrease of the carbon-dioxide emission has emerged as one of the most urgent tasks in engineering. In this work, the possibility for the application of the polymer-based, dense, mixed matrix membranes for flue gas treatment was tested. The task was to test a potential decrease in the permeability and selectivity of a mixed-matrix membrane in the presence of moisture and at elevated temperature. Membranes are based on two different poly(ethylene oxide)-based polymers filled with two different zeolite powders (ITR and IWS). An additive of detergent type was added to improve the contact properties between the zeolite and polymer matrix. The measurements were performed at three different temperatures (30, 60, and 90 °C) under wet conditions, with partial pressure of the water equal to the vapor pressure of the water at the given temperature. The permeability of carbon-dioxide, hydrogen, nitrogen, and oxygen was measured, and the selectivity of the carbon-dioxide versus other gases was determined. Obtained results have shown that an increase of temperature and partial pressure of the vapor slightly increase both the selectivity and permeability of the synthesized membranes. It was also shown that the addition of the zeolite powder increases the permeability of carbon-dioxide while maintaining the selectivity, compared to hydrogen, oxygen, and nitrogen.


Author(s):  
Yuanyue Wu ◽  
Zhen Wang ◽  
Liang Zhu ◽  
Kaijun Xiao ◽  
Yurong Yin ◽  
...  

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