A polymer analog of dimethyl sulfoxide: Catalytic activity of crosslinked polymeric sulfoxides in nucleophilic reactions under the conditions of three-phase catalysis

1984 ◽  
Vol 49 (9) ◽  
pp. 2096-2102 ◽  
Author(s):  
Václav Janout ◽  
Hana Hrudková ◽  
Pavel Čefelín
Keyword(s):  
Catalytic Activity ◽  
Alkali Metals ◽  
Crosslinking Agent ◽  
Substitution Reactions ◽  
Alkyl Bromides ◽  
Three Phase ◽  
Polystyrene Matrix ◽  
Crosslinked Polystyrene ◽  
Solid Liquid ◽  
Matrix Extension

An investigation was made of the catalytic activity of polymeric sulfoxides, P-(CH2SOCH2-)n-R' where P is the crosslinked polystyrene matrix (divinylbenzene as the crosslinking agent), R is H or CH3, and n is 1, 2, or 3, in nucleophilic substitution reactions between alkyl bromides and phenoxides, iodides, thiocyanates and cyanides of alkali metals under the conditions of liquid-solid-liquid (L-S-L) three-phase catalysis (TC). The effect of the structure of polymeric sulfoxides on their activity under the conditions of TC was studied; the strongest catalytic activity was found with polymeric sulfoxides having the optimal ratio between the functional groups and hydrophobic polymer matrix. Extension of the pendant sulfoxide chain has no pronounced effect of the catalytic activity of polymers.

Reaction of 1-bromobutane with potassium cyanide under conditions of three-phase catalysis: Activity of new polymeric catalysts

1982 ◽  
Vol 47 (7) ◽  
pp. 1818-1825 ◽  
Author(s):  
Václav Janout ◽  
Pavel Čefelín
Keyword(s):  
Catalytic Activity ◽  
Functional Groups ◽  
Polymer Chain ◽  
Quaternary Ammonium ◽  
Potassium Cyanide ◽  
Essential Difference ◽  
Three Phase ◽  
Crosslinked Polystyrene ◽  
Solid Liquid

Six new polymeric catalysts active in the reaction between 1-bromobutane and potassium cyanide under conditions of liquid-solid-liquid three-phase catalysis (L-S-L TC) were prepared. The catalysts are based on a crosslinked polystyrene carrier of polar and dipolar functional groups of the type of quaternary ammonium and phosphonium, and also thioether , sulphoxide and sulphone groups. With respect to catalytic activity, an essential difference has been proved to exist between polymers where functional groups of the thio ether, sulphoxide, and sulphone type are bound as pendent on the polymer chain, and those where similar functional groups are part of the network. Compared with the water-toluene system, the water-chlorobenzene system usually gives higher yields.

Polymer structure and catalytic activity of ion exchangers

1981 ◽  
Vol 46 (7) ◽  
pp. 1577-1587 ◽  
Author(s):  
Karel Jeřábek
Keyword(s):  
Catalytic Activity ◽  
Ethyl Acetate ◽  
Active Sites ◽  
Crosslinking Agent ◽  
Reaction Medium ◽  
Polymer Structure ◽  
Local Concentration ◽  
Ion Exchangers ◽  
Styrene Divinylbenzene ◽  
Kinetics Of

Catalytic activity of ion exchangers prepared by partial sulphonation of styrene-divinylbenzene copolymers in reesterifications of ethyl acetate by methanol and propanol, hydrolysis of ethyl acetate and in synthesis of bisphenol A has been compared with data on polymer structure of these catalysts and with distribution of the crosslinking agent, divinylbenzene, calculated from literature data on kinetics of copolymerisation of styrene with divinylbenzene. It was found that the polymer structure of ion exchangers influences catalytic activity predominantly by changing the local concentration of acid active sites. The results obtained indicated that the effect of transport phenomena on the rate of catalytic reactions does not depend on the degree of swelling of the ion exchangers in reaction medium but it is mainly dependent on the relative affinity of reaction components to the acid groups or to the polymer skeleton.

A new three-phase heterocrystal catalysts and their superior treatment efficiency for tetracycline

2016 ◽  
Vol 10 (03) ◽  
pp. 1750015
Author(s):  
Feng-Rui Wang ◽  
Hui-Ping Sun ◽  
Yan Wang ◽  
Jin-Ku Liu ◽  
Yi Fang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Band Structure ◽  
Antibiotic Residues ◽  
Treatment Efficiency ◽  
Electron Hole ◽  
Three Phase ◽  
Catalytic Material ◽  
Water Based ◽  
The Stability ◽  
Functional Components

An easy recyclable and interesting Ag3PO4@Pt@TiO2 (APTP) three-phase heterocrystal chains were self-assembled by the cohesive action and chemical construction of polyvinylpyrrolidone (PVP). We found that a new electron–hole transmission path has been built via the rematch of the band structure of Ag3PO4, Pt and TiO2 which extends the light absorption and promoted the electron–hole separation to treat the antibiotic residues in the water. Based on the thorough investigations, a new catalytic material was provided for antibiotics degradation. The catalytic activity of APTP toward the degradation of tetracycline solution was enhanced by 166.67% and the stability increased remarkably compared with pure Ag3PO4 through the integration of different functional components.

The synthesis and catalytic activity of polymeric compounds containing alkali metals

1975 ◽  
Vol 17 (7) ◽  
pp. 1636-1644 ◽  
Author(s):  
V.S. Glukhovskoi ◽  
Yu.A. Litvin ◽  
I.F. Gainulin
Keyword(s):  
Catalytic Activity ◽  
Alkali Metals ◽  
Polymeric Compounds

A three-phase solid-liquid-gas slug flow mechanistic model coupling hydrate dispersion formation with heat and mass transfer

2018 ◽  
Vol 178 ◽  
pp. 222-237 ◽  
Author(s):  
Carlos L. Bassani ◽  
Fausto A.A. Barbuto ◽  
Amadeu K. Sum ◽  
Rigoberto E.M. Morales
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Slug Flow ◽  
Mechanistic Model ◽  
Model Coupling ◽  
Three Phase ◽  
Solid Liquid

Numerical Modeling of Microporosity Formation in Aluminum-Rich Aluminum-Copper Alloys in Microgravity Conditions

2000 ◽  
Author(s):  
M. Xiong ◽  
A. V. Kuznetsov
Keyword(s):  
Copper Alloys ◽  
Heat Transfer Fluid ◽  
Gas Phases ◽  
Alloy Casting ◽  
Cu Alloy ◽  
Aluminum Copper Alloys ◽  
Three Phase ◽  
Microgravity Conditions ◽  
Parametric Analyses ◽  
Solid Liquid

Abstract The microporosity formation in a vertical unidirectionally solidifying Al-4.1%Cu alloy casting is modeled in both microgravity and standard gravity as well as in the conditions of decreased (Moon, Mars) and increased (Jupiter) gravity. Due to the unique opportunities offered by a low-gravity environment (absence of metallostatic pressure and of natural convection in the solidifying alloy) future microgravity experiments will significantly contribute to attaining a better physical understanding of the mechanisms of microporosity formation. One of the aims of the present theoretical investigation is to predict what microporosity patterns will look like in microgravity in order to help plan a future microgravity experiment. To perform these simulations, the authors suggest a novel three-phase model of solidification that accounts for the solid, liquid, and gas phases in the mushy zone. This model accounts for heat transfer, fluid flow, macrosegregation, and microporosity formation in the solidifying alloy. Special attention is given to the investigation of the influence of microporosity formation on the inverse segregation. Parametric analyses for different initial hydrogen concentrations and different gravity conditions are carried out.

Sign in / Sign up

Export Citation Format

Share Document