181-28-2Relevant articles and documents
Phosphorus promoted SO42-/TiO2 solid acid catalyst for acetalization reaction
Zhong, Shaofeng,Ou, Qiongrong,Shao, Linjun
, p. 3005 - 3008 (2015/11/27)
A novel phosphorus modifed SO42-/TiO2 catalyst was synthesized by a facile coprecipitation method, followed by calcination. The catalytic performance of this novel solid acid was evaluated by acetalization. The results showed that the phosphorus was very effcient to enhance the catalytic activity of SO42-/TiO2. The solid acid owned high activity for the acetalization with the yields over 90%. Moreover, the solid acid could be reused for six times without loss of initial catalytic activities.
Synthesis of a novel melamine-formaldehyde resin-supported ionic liquid with Bronsted acid sites and its catalytic activities
Xing, Guiying
, p. 1369 - 1374 (2013/10/01)
Bronsted acidic ionic liquid immobilized on a melamine-formaldehyde resin (AIL-MFR) was synthesized through the reaction of melamine-formaldehyde resin (MFR) with 1,4-butanesulfonate. Using PEG-2000 as the additive, the MFR can be prepared in regular microspheres with an average diameter of 3.97 μm and surface area of 9.09 m2 g-1. The AIL-MFR had high acidity of 2.93 mmol g-1, mainly from the sulfonic groups. The catalysis results showed that the AIL-MFR had high activity and stability for acetalization with excellent conversions and yields for most substrates. Furthermore, immobilization of the acidic ionic liquid on the MFR made the recycling of the catalyst convenient.
Self-assembly synthesis of a high-content sulfonic acid group functionalized ordered mesoporous polymer-based solid as a stable and highly active acid catalyst
Wang, Wei,Zhuang, Xin,Zhao, Qingfei,Wan, Ying
supporting information; body text, p. 15874 - 15886 (2012/09/05)
A stable and highly active ordered mesoporous polymer-based acid catalyst has been prepared via a simple surfactant templating approach and oxidation treatment. The composition and nanostructure are characterized by XRD, NMR, XPS, TEM, nitrogen sorption, elemental and chemical analysis. The sulfonic acid groups have been anchored within the well-arranged channels of the polymer-based matrix. Even with a high -SO3H group loading (up to about 27.4 wt%) on the mesoporous polymer-based material, the ordered mesostructure and high surface area (~400 m2 g-1) can be retained and the functional moieties are highly chemically accessible. With the large number of acid sites (0.93-2.38 H+ mmol g-1 determined by acid-base titration) and the hydrophobic character, the mesoporous polymer-based solid exhibits unique catalytic performance in acid-catalyzed reactions such as condensation and acetalization, not only high activity (per site yield of bisphenol-A is over 45 in the condensation of phenol and acetone) but also excellent stability. Loss in acidic loading and activity is negligible even after the catalyst is reused 20 times in the acetalization of butanediol and aldehyde. The stability is most likely attributed to the hydrophobic nature of the mesoporous polymer-based solids, which favors the diffusion of water and thereby inhibits the poisoning of acidic sites caused by water generating in the reaction. Moreover, with large mesopores, the diffusion of reactants and products can be promoted and hence the catalytic activity can be further increased.