6 results about "Alkene epoxidation" patented technology

The invention belongs to the technical field of preparation of epoxy compounds, and relates to an olefin epoxidation method. According to the method, reaction raw materials containing olefin and hydrogen peroxide are subjected to a reaction on a fixed bed reactor using a forming catalyst formed by compounding a titanium silicalite molecular sieve and an organic matter carbonized product. The catalyst is obtained by extrusion molding, drying and carbonization of a mixture containing a titanium silicalite molecular sieve, a benzene ring-containing polymer and a dispersing agent, the obtained catalyst has high mechanical strength and is suitable for olefin epoxidation fixed bed reaction. The method provided by the invention can effectively inhibit formation of byproducts, and realizes efficient utilization of hydrogen peroxide and efficient proceeding of olefin epoxidation reaction.

A polyacid-based supramolecular complex catalyst for catalyzing olefin epoxidation at normal temperature, a preparation method and application thereof, and a molecular formula thereof is as follows: {[Co(cmbpy)(H2O)4](beta-Mo8O 26 ) 0.5}·H2O, wherein, cmbpy is deprotonated 1-(carboxymethyl)-(4,4'-bipyridine). A cobalt sulfate, 1-(carboxymethyl)-4,4'-bipyridinium hydrochloride and (NH4)6Mo7O 24 ·4H2O are added into an ethanol solution, stirred for 2 hours, the pH value is adjusted to 5.84 by using an inorganic base, transferred to a reaction kettle with a polytetrafluoroethylene liner, sealed, heated to 85 DEG C, reacted under hydrothermal conditions for 4 days, naturally cooled to room temperature after the reaction is completed, washed and separated to obtain the polyacid-based supramolecular complex catalyst. The advantage is that the synthesis method is simple, the synthesis time is short, the synthesis yield is high, and the catalyst can be used for selective oxidation of cyclooctene.

This invention provides a hierarchical porous TS-1 molecular sieve, its preparation method, and its applications, belonging to the field of catalysts. The method for preparing the hierarchical porous TS-1 molecular sieve involves directly adding a silanizing agent to a crystallization system to produce a hierarchical porous TS-1 molecular sieve with uniform particle size distribution and high crystallinity. This molecular sieve also features a large specific surface area and large pore volume, and exhibits high selective oxidation activity in macromolecular oxidation reactions. Specifically, this invention uses the synthesized hierarchical porous TS-1 molecular sieve to catalyze the epoxidation reaction of C4-C6 olefins. Results show that the olefin conversion rate is not less than 20%, and the effective utilization rate of hydrogen peroxide is not less than 80%, effectively solving the problems of hindered feedstock diffusion and easy pore blockage in C4-C6 olefin oxidation reactions, thereby improving its catalytic activity and stability.

The application of binaphthyl Salen cobalt molecular catalyst modified BiVO4 photoanode belongs to the field of photoelectrocatalysis technology and organic synthesis cross. BiOI film is deposited on FTO conductive glass by electrochemical deposition method, and then is converted into BiVO4 photoanode substrate by calcination; 3-hydroxy substituted binaphthyl Salen cobalt molecular catalyst CoL is synthesized; CoL is loaded on the surface of BiVO4 by cyclic voltammetry electrodeposition to obtain a hybrid photoanode. The photoanode is applied to the photoelectrocatalytic olefin epoxidation reaction, water is used as oxygen source, and acetone-water is used as electrolyte. The strong interface coupling between the catalyst and BiVO4 is strengthened by the electrodeposition of the molecular catalyst strategy, and the interface charge transport efficiency, reaction conversion rate and selectivity are improved. The conversion rate of styrene reaches 99%, the selectivity of epoxide reaches more than 90%, and the stability is excellent. The application provides a new way for green and efficient synthesis of epoxide, and has wide application prospect.

This invention discloses a fully crystalline Ti-MWW molecular sieve catalyst, its preparation method, and its applications. The UV-Raman spectrum of the fully crystalline Ti-MWW molecular sieve catalyst is at 343±4 cm⁻¹. ‑1 484±4cm ‑1 699±4cm ‑1 and 1097±4cm ‑1 A spectral peak appears at 699±4cm. ‑1 The intensity of the spectral peak is 343±4 cm⁻¹. ‑1 The peak intensity is 0.5 to 10 times that of the spectral peak, 1097 ± 4 cm⁻¹ ‑1 The intensity of the spectral peak is 343±4 cm⁻¹. ‑1 The spectral peak intensity is 0.5 to 10 times that of the standard. The Ti-MWW molecular sieve catalyst, when used in olefin epoxidation reactions, exhibits high olefin conversion, high epoxide selectivity, and good catalytic stability.

The application discloses an epoxidation catalyst and a liquid-phase preparation method. Titanium is grafted into the skeleton of a carrier SiO2 by adopting a liquid-phase static grafting method. The introduction of rare earth elements improves the stability of the carrier structure and active components, strengthens the directional grafting of titanium and the distribution of active sites, improves the activity and stability of the catalyst in olefin epoxidation, and avoids the corrosion of equipment and the poisoning of copper-based catalysts in the POSM process in the whole process without introducing chlorine elements.