Zeolite-based catalysis for isobutene conversion into chemicals and fuel additives. A review

International audienceIsobutene (IB), the most reactive molecule in the C4 raffinate, is a raw material of greatindustrial significance. It is extensively used in the manufacturing process of rubber, fuel additives,fine chemicals, agricultural chemicals, plastics and antioxidants. Heterogeneous catalysts and particularlyzeolites are playing a major role in these applications. The aim of this review is to examinethe relevant processes involving IB as reagent and zeolites as acid catalysts. The following reactionsare successively covered: Prins condensation, IB dimerization, IB—methanol/ethanol etherification,IB—glycerol etherification, IB amination, and phenol tert-butylation. While reasonably comprehensiveand broad, the present survey is not necessarily exhaustive. The mechanistic aspects of the titledreactions, the role of zeolite catalysts and their topology/active sites on the product selectivity aremainly explored

CRIMA ORGANIZATĂ – O AMENINŢARE LA ADRESA ORDINII DE DREPT DIN UNIUNEA EUROPEANĂ

Aderarea ţării noastre la Uniunea Europeană, paşii făcuţi în scopul constituirii pieţei uniceeuropene şi consecinţa înlăturării oricăror restricţii în privinţa circulaţiei persoanelor, serviciilor,mărfurilor şi a capitalurilor (articolul 39, 56, 131 din Tratatul de la Roma1), ne determină să credem căva duce nu numai la o creştere economică, scop prioritar şi cauză a creării Uniunii Europene, dar şi lao creştere a criminalităţii, datorită posibilităţilor mult mai ample de mobilitate a persoanelor de careinfractorii pot profita, şi în special a celei organizate, apărând premisele cooperării internaţionale îndomeniul criminalităţii

Towards Platform Chemicals from Bio-based Ethylene: Heterogeneous Catalysts and Processes

International audienceWith stricter ecological regulation and reduction of fossil feedstock, the research works have been orientated to renewable resources. Various bio-based molecules were proposed for replacing the platform chemicals based on crude oil, but there are not yet well established processes for producing these chemicals at large scale. As a result, in the short to mid-term, a main impact will be expected from the production of bio-based bulk chemicals having identical structure with that of the today’s bulk chemicals. Among them, ethylene, which is a key intermediate for the production of platform molecules. The commercial method for producing ethylene is based on steam thermal cracking, but emerging method using alternative sources (natural gas, coal, biomass) are very promising processes. For example, the high-volume production of ethylene by ethanol dehydration became economically feasible application. This review summarizes the advances of catalysts, processes and fundamental understanding of reaction mechanisms in ethylene conversion to other high value hydrocarbons, including propylene, butenes and aromatics BTX

Développements de nouveaux catalyseurs mésoporeux et de nouveaux outils pour l'oligomérisation de l'éthylène

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Nanooxides

International audienc

Styrene oxidation with H2O2 over Ti-containing molecular sieves with MFI, BEA and MCM-41 topologies

A comparative study concerning the use of Ti-containing molecular sieves with MFI (TS-1), BEA (Ti-beta) and MCM-41 (TiMCM-41) topologies for the styrene oxidation in liquid phase by hydrogen peroxide was performed. The major reactions were epoxidation of styrene, the isomerization of styrene oxide into phenylacetaldehyde (PhAA) as well as its oxidative cleavage into benzaldehyde (BzA) and formaldehyde. A high selectivity to PhAA was observed over TS-1, whereas the BzA formation is predominant on Ti-beta and TiMCM-41. Also, the influence of the reaction time and the nature of solvent on the styrene conversion, the selectivity of hydrogen peroxide consumption and on the product distribution were studied

Nano-oxides

International audienc

Catalysis by polymers. VI. the epichlorohydrin esterification catalyzed by poly(N,N-dimethyl-p-vinylbenzyl-amine)

International audienc