53results about How to "Extended one-way service life" patented technology

The invention discloses a method for producing an ethylene cracking material through liquefied gas hydrogenation. The method is characterized in that liquefied gas and hydrogen pass through a hydrogenation reactor through a cocurrent flowing mode, then are contacted with a hydrogenation catalyst under hydrogenation technical condition and subjected to a reaction; the hydrogenation reactor comprises more than two reaction segments, and according to a contact sequence with a reaction material, the activity of the catalyst in a downstream reaction segment is higher than the activity of the catalyst in an upstream reaction segment. The method reduces the relative average reaction speed at an entrance of a catalyst bed layer, changes problem of large relative average reaction speed at the entrance of the catalyst bed layer, a difference of the average reaction speed of each segment of the catalyst bed layer is greatly reduced, and the relative average reaction speed of each segment of the catalyst bed layer is more uniform.

The invention discloses a benzene oxidation method. The method comprises the step of enabling a liquid mixture to sequentially flow through a first catalyst bed layer and a second catalyst bed layer under oxidation reaction conditions, wherein the liquid mixture contains benzene, an oxidant and an optional solvent, the first catalyst bed layer and the second catalyst bed layer each is loaded with titanium silicalite molecular sieves, and the superfacial velocity of the liquid mixture flowing through the first catalyst bed layer is lower than that of the liquid mixture flowing through the second catalyst bed layer. According to the method, in a long-time continuous operating process, the single-pass service lives of the titanium silicalite molecular sieves as a catalyst can be effectively prolonged, the regeneration frequency is lowered, the production efficiency of a device is increased, and the operating cost of the device is reduced; and the availability of the oxidant is relatively high. In addition, the method is high in operability, in a practical application process, two reaction zones are arranged in series, and the inner diameter of the reaction zone located at upstream is enabled to be greater than that of the reaction zone located at downstream.

The invention discloses a method for preparing ethylene cracking feed by hydrogenation of liquefied gas. Liquefied gas and hydrogen pass through a hydrogenation reactor in a parallel flow manner and is in contact with hydrogenation catalysts for reaction; two or more hydrogenation catalyst bed layers are arranged in the hydrogenation reactor; the hydrogen enters the two or more hydrogenation catalyst bed layers from different feeding openings respectively; the amounts of the hydrogen entering all the hydrogenation catalyst bed layers are 5 to 95 volume percent of chemical hydrogen consumption required by reaction separately; except the last hydrogenation catalyst bed layer, the sum of total amounts of the hydrogen entering other hydrogenation catalyst bed layers is smaller than the required chemical hydrogen consumption. According to the method disclosed by the invention, by controlling partial pressures of the hydrogen entering different catalyst bed layers, the reaction speed is effectively controlled, and accurate control over the conversion rate is realized, so that reaction temperature rise of all sections of catalyst bed layers in the reactor is reduced, further the carbon deposit speed of the catalyst is retarded, and the single-pass service life of the catalyst is prolonged.

The invention discloses a method for preparing sulfone. The method comprises that a contact reaction between a reaction mixture and a titanium-silicalite molecular sieve is performed in a reactor forobtaining a product mixture containing sulfone, wherein the reaction mixture comprises thioether, an oxidizing agent and an optional solvent, and when the selectivity of the target oxidation product is lower than an expected value, the method also comprises increasing the pressure in the reactor until the selectivity of the target oxidation product rises above the expected value. The method can effectively delay the deactivation rate of the titanium-silicon molecular sieve which is used as a catalyst, prolong the one-way service life of the titanium-silicon molecular sieve, reduce the regeneration frequency of the titanium-silicon molecular sieve, reduce the production cost, and also can improve the operation efficiency of the device.

The invention discloses an oxidation method for thioether. The method comprises the step of subjecting a liquid mixture and a titanium-silicate molecular sieve to contacting under the condition of oxidation reaction, wherein the liquid mixture comprises thioether, at least one oxidant, at least one alkaline substance and at least one optional solvent; and when selectivity of a target oxidation product is lower than an expected value, the method also comprises the steps of improving the quality of the alkaline substance in the liquid mixture and optionally improving the quality of the oxidant in the liquid mixture. The method provided by the invention can maintain the selectivity of the target oxidation product at a high level for a long time, effectively prolong the single-way service life of the titanium-silicon molecular sieve used as a catalyst, and reduce regeneration frequency of the catalyst.

The invention provides a method for oxidizing olefins, the method comprising: under oxidation reaction conditions, making a liquid phase mixture containing olefins, an oxidizing agent and optionally an organic solvent flow through a catalyst bed in a rectification column, wherein, The catalyst bed layer contains titanium silicon molecular sieve. By adopting the method of the present invention to oxidize olefins, relatively stable oxidant conversion rate and high selectivity of target oxidation products can be obtained during long-term continuous operation. In particular, by adopting the method of the present invention, the selectivity of epoxides is high, and the selectivity of by-products is low, thereby reducing the difficulty of subsequent separation and purification.

The invention discloses a method for oxidizing alkenes, which comprises contacting and reacting a liquid mixture with a titanium-silicon molecular sieve under oxidation reaction conditions, and removing the heat of reaction with a heat exchange medium during the contact reaction process, the liquid mixture containing Olefin, at least one oxidant, and optionally at least one solvent, wherein, when the target oxidation product drops below a desired value, the method further includes adjusting the conditions of the heat exchange to reduce the amount of heat of reaction removed and may Optionally increase the quality of the oxidant in the liquid mixture to increase the selectivity of the target oxidation product until the expected value is met. The method can maintain the selectivity of the target oxidation product at a high level during long-term continuous operation, effectively prolongs the single-pass service life of the titanium-silicon molecular sieve as a catalyst, and reduces the regeneration frequency of the catalyst.

The invention discloses a preparation method for a sulphone. The preparation method for the sulphone comprises contacting a reaction mixture with a titanium silicate molecular sieve in a reactor for reaction, so as to obtain a product mixture containing the sulphone, wherein the reaction mixture contains a sulfur ether, an oxidant and a selectable solvent. When the conversion rate of the oxidant is lower than an expected value, the method additionally comprises improving the temperature of a liquid mixture until the conversion rate of the oxidant rises again to a value equal to or more than the expected value. The method is capable of effectively delaying the deactivation speed of the titanium silicate molecular sieve used as a catalyst, prolonging the one-way service life of the titanium silicate molecular sieve, reducing the regeneration frequency of the titanium silicate molecular sieve and reducing production cost, but also can improve the operation efficiency of an employed apparatus.

The present invention relates to a method for oxidation of allyl alcohol, the method comprising: under oxidation reaction conditions, making the reaction feed containing allyl alcohol, oxidant and optional at least one solvent sequentially flow through the first catalyst bed layer to the last The nth catalyst bed layer, each of the catalyst beds is filled with at least one titanium-silicon molecular sieve, and the titanium-silicon molecular sieve is at least partly modified titanium-silicon molecular sieve, and the modified titanium-silicon molecular sieve is a modified titanium-silicon molecular sieve. The modified titanium-silicon molecular sieve includes contacting the titanium-silicon molecular sieve as a raw material with a modifying solution containing nitric acid and peroxide. The method can prolong the single-pass service life of the catalyst, and can stabilize the conversion rate of the raw material, the effective utilization rate of the oxidant and the selectivity of the target oxidation product at a relatively high level even if the catalyst is operated continuously for a long period.

The invention discloses a method for oxidizing olefins, which comprises contacting and reacting a liquid mixture containing olefins and at least one oxidizing agent with titanium-silicon molecular sieves in a reactor under oxidation reaction conditions, wherein the selectivity of the target oxidation product is reduced to Below the expected value, the reaction temperature and optionally the mass of oxidant in the liquid mixture is increased until the target oxidation product meets the expected value. The method can effectively prolong the single-pass service life of the titanium-silicon molecular sieve used as the catalyst, reduce the regeneration frequency of the catalyst, improve the production efficiency, improve the operation stability, and prolong the total service life of the catalyst.

The invention discloses a sulfide oxidation method, which comprises continuously feeding a liquid mixture into a fixed-bed reactor, making the liquid mixture flow through the catalyst bed under oxidation reaction conditions, so as to be mixed with the catalyst bed packed in the catalyst bed. Titanium-silicon molecular sieve contact reaction, the liquid mixture contains thioether, at least one oxidizing agent and optionally at least one solvent, wherein the method also includes when the conversion rate of the oxidizing agent and / or the selectivity of the target oxidation product decreases to a certain extent , increase the weight hourly space velocity of thioether until the conversion rate of the oxidant and / or the selectivity of the target oxidation product increase to meet the requirements. The method of the present invention can maintain the conversion rate of the oxidant and / or the selectivity of the target product in a relatively high range even if it operates continuously for a long period, thereby effectively prolonging the single-pass service life of the titanium-silicon molecular sieve as a catalyst and reducing the regeneration frequency. Extend the stable operation time of the device. The method of the invention is simple and easy to implement, and is beneficial to industrial production and application.

The present invention discloses an allyl chloride oxidation method, which comprises that a reaction material containing allyl chloride, an oxidizing agent and a solvent sequentially flows through catalyst bed layers from 1 to n under an oxidation reaction condition, wherein n is an integer of more than 2, and the catalyst bed layer is filled with at least a titanium-silicon molecular sieve; and when the reaction material passes through the catalyst bed layers from 1 to n, at least a flow carrier is introduced into the position between at least a pair of the adjacent catalyst bed layers among the catalyst bed layers from 1 to n, such that the apparent velocity of the reaction stream positioned in the downstream catalyst bed layer is higher than the apparent velocity of the reaction stream positioned in the upstream catalyst bed layer in the pair of the adjacent catalyst bed layers by adopting the flowing direction of the reaction material as the reference. With the method of the present invention, the one-way service life of the titanium-silicon molecular sieve can be effectively prolonged, the effective utilization rate of the oxidizing agent can be improved, and the target product selectivity can be improved.

The invention discloses a sulfoether oxidation method. The method comprises the steps that a liquid mixture is continuously fed into a fixed-bed reactor, and the liquid mixture flows through catalyst bed layers under the oxidation reaction condition to be reacted with titanium silicalite molecular sieves filled in the catalyst bed layers in a contacted mode, wherein the liquid mixture contains sulfoether, at least one oxidizing agent and at least one selectable solvent. The method further comprises the step that when the conversion rate of the oxidizing agent and / or the selectivity of a target oxidation product decreases to a certain degree, feeding of the sulfoether is stopped for a period of time, and then feeding of the sulfoether is restored again. By means of the sulfoether oxidation method, the conversion rate of the oxidizing agent and / or the selectivity of the target oxidation product can be maintained within a higher range for a long time, and the one-way service life of the titanium silicalite molecular sieves serving as a catalyst is effectively prolonged. In addition, the sulfoether oxidation method is simple and easy to carry out.