35results about How to "Maintain active stability" patented technology

The present invention provides an agarose gel separation medium which is uniform in size, controllable and has high hydrophility and high porousness, and can be used for making separation and purification of biological active material. Its preparation method is characterized by that it adopts the following steps: (1) dissolving a certain quantity of agarose in a certain quantity of water under the heating condition to obtain agarose aqueous solution with a certain concentration, using pressure to make said aqueous phase by passed through microporous membrane and make it feed into oil phase to obtain emulsion drop with uniform size; and (2). transferringsaid emulsion into cooling device, under the condition of adopting programmed temperature-falling and slow-mechanically stirring process cooling to below 15 deg.C and making gel be solidified so as to obtain the invented agarose gel microspheres with uniform size.

A Bi / Bi 2 SiO 5 The preparation method and application of a photocatalyst belong to the controllable preparation of Bi / Bi-based photocatalytic material composite system, CO 2 Reduction of resources conversion and utilization, artificial photosynthesis field, can solve Bi 2 SiO 5 Due to the narrow photoresponse range and high photogenerated electron-hole recombination rate, Bi(NO 3 ) 3 ·5H 2 O and Na 2 SiO 3 ·9H 2 O is a bismuth source and a silicon source, ethylene glycol and deionized water are the solvents, and the NaOH solution is the pH value adjuster. Using a one-step hydrothermal method, the pH value of the reaction solution is adjusted between 9 and 14 by adjusting the concentration of the NaOH solution. High purity Bi / Bi 2 SiO 5 Photocatalysts that ultimately increase Bi 2 SiO 5 Photocatalytic reduction of CO 2 The activity, selectivity and stability provide new methods and new applications for the preparation of high-efficiency novel elemental Bi / Bi-based photocatalytic material composite systems.

The invention provides a method for producing naphtha and clean gasoline by catalytic cracking diesel oil. The method comprises the following steps of mixing the catalytic cracking diesel oil and hydrogen gas; enabling the mixture to enter the middle part of a reverse sequence filling hydrocracking reactor-hydrofining reactor to be mixed with cracking products from the hydrocracking reactor; enabling the mixture to enter the hydrofining reactor to perform a hydrofining reaction so as to remove impurities such as sulfur and nitrogen; performing an olefin saturated reaction and arene hydrogenation saturation; performing cutting processing on products after the hydrofining; using distillate oil below 165 DEG C as a naphtha product to be used as a raw material for a catalytic reforming unit; using distillate oil being 165 to 205 DEG C as a clean gasoline conditioning ingredient; returning distillate oil being 205 to 320 DEG C into the top of the reverse sequence filling hydrocracking reactor-hydrofining reactor; performing hydrocracking and hydrofining reactions; returning distillate oil being higher than 320 DEG C into a catalytic cracking device for further cracking, or enabling the distillate oil being higher than 320 DEG C to enter other hydrogenation devices for processing treatment. The method has the advantages that high yield of naphtha products is taken as the goal; the clean gasoline can be produced at the same time.

The invention relates to a method for producing propylene from methanol or dimethyl ether, and mainly solves the problems that a catalyst is easily inactivated due to short reaction residence time and the reaction conditions are frequently fluctuated and the operation is unstable caused by frequent switch and reproduction in the prior art. The method for producing the propylene from the methanol or the dimethyl ether comprises the following steps of: a) making oxygen-containing compounds and a diluent enter a fluid bed reactor from the bottom; b) performing contact reaction on the raw materials and a ZSM-5 molecular sieve catalyst at the temperature of between 400 and 550 DEG C under the pressure of between 0.02 and 0.5 MPa; c) separating gas-phase material flow out of the top of the fluid bed reactor to obtain the propylene; d) extracting the reaction heat by using a heat exchanger; e) controlling the inactivated catalyst with a sliding valve and feeding the catalyst into a regenerator through a catalyst spending inclined tube, reacting the inactivated catalyst with air at the temperature of between 480 and 700 DEG C to burn off carbon deposit, and exhausting waste gas; and f) controlling the regenerated catalyst by using the sliding valve and feeding the regenerated catalyst to the upper part of the fluid bed reactor for circulation through a catalyst regenerating inclined tube. The technical scheme of the invention better solves the problems, and can be applied to the industrial production of the propylene.