13 results about "Fixed bed" patented technology

The invention relates to a method for directly preparing propylene from crude methanol, wherein, in an integrated unit for preparing the methanol and preparing the propylene from the methanol, the crude methanol directly enters a multistage adiabatic fixed bed reactor loaded with an acid molecular sieve catalyst without rectification and purification to prepare low carbon olefin with the propyleneas a main component. In the method, steam and circulating hydrocarbon as diluent, and a mixture of the crude methanol and water is used for interstage cold shock to control reaction temperature of the reactor in each stage. The method helps obtain high propylene yield, and obviously reduce investment and energy consumption of the integrated unit for preparing the methanol and preparing the propylene from the methanol.

The invention discloses a coproduction method of 1, 2-propanediamine and dimethyl piperazine, which comprises the following steps of: mixing ammonia and isopropanol amine, pre-heating for vaporization, filling steam into a fixed-bed reactor, performing reaction in the presence of a catalyst for condensation and amination and under conditions with the pressure of 1.0MPa to 4.0MPa, the temperature of 300 DEG C to 350 DEG C and the contact time of 1.0-3.0s to obtain product stream of 1, 2-propanediamine, 2, 5-dimethyl piperazine, 2, 6-dimethyl piperazine, unreacted ammonia and unreacted isopropanol amine, and distilling the product stream for separation to obtain the 1, 2-propanediamine, 2, 5-dimethyl piperazine and 2, 6-dimethyl piperazine; wherein the weight ratio of the ammonia and the isopropanol amin is (10-16):1, and the catalyst for condensation and amination comprises the following ingredients by weight percentage: 97-99 percent of HZSM-5 (H-type zeolite sieve of molecular porosity 5) zeolite and 1-3 percent of phosphorus. The coproduction method is mainly applied in preparation of the 1, 2-propanediamine and the dimethyl piperazine.

A work surface guide for portable hand-operated power tools allows their adaptation to a fixed-bed form (for example, a circular saw may be used as a radial arm saw or sliding miter saw). A pair of parallel rails are spaced laterally outwardly and above a table or other work surface so that the power tool may slide along these rails to cut matter located in a cutting area situated below and beneath the rails (and protruding from the edge of the work surface beneath the rails). A board fence is pivotally attached to one of the rails to extend onto the work surface, thereby allowing the board fence to be adjusted to some desired angle, a board to be situated against the board fence to protrude beneath the rails and into the cutting area, and the power tool to be run along the rails to cut the board.

An apparatus for the photocatalyitc oxidation of common industrial effluent contaminants in aqueous solution includes a reactor and a thin film photocatalyst fixed to a support material like Cuddapah stone. The support material is preferably an inert material. The TiO2 preformed does not contain any adsorbent for making the thin film photocatalyst, The catalytic runs were carried out over TiO2 thin film fixed bed reactor. The study is extended to the immobilization of preformed TiO2 with a binder for making thin film using a simple spray technique on inert Cuddapah stone. This method of immobilization require no thermal treatment of the catalyst at high temperatures. The method is applicable for the photocatalytic treatment of industrial effluents at a higher scale. Also it is a method for preparing a photocatalyst adopted for the oxidation of industrial common effluent by simple spray technique. Also it is a method and apparatus for destroying industrial common effluent contaminants in aqueous solution

The technical problem to be solved by the invention is to provide a preparation method for a catalyst for preparing chloroethylene via ethane oxychlorination. The catalyst contains rare-earth elements, alkali metal elements, iron element, tin element and titanium dioxide, and is applied to a fixed bed reactor; the preparation method for the catalyst is simple in process, low in reaction temperature, and reduced in energy consumption; air is used as a raw material gas, so that the cost is low; and the prepared catalyst has good catalytic activity while being applied to a reaction for preparing chloroethylene via ethane oxychlorination, the conversion rate of ethane is 80-100%, and the selectivity of chloroethylene is 40-68%.

Provided is a catalyst system for oxidative dehydrogenation, a reactor for oxidative dehydrogenation including the catalyst system, and a method of performing oxidative dehydrogenation using the reactor. In the catalyst system, a fixed-bed reactor is filled with a catalyst for oxidative dehydrogenation in an n-stage structure (n being an integer of 2 or more), wherein each stage of the n-stage structure satisfies Equations 1 and 2 as claimed so that the concentration of an active ingredient included in the catalyst gradually increases in the direction in which reactants are fed into the reactor. Heat generated inside the reactor may be effectively controlled during oxidative dehydrogenation, thereby improving conversion rate, selectivity, and yield. In addition, catalyst deterioration may be reduced, thereby improving long-term stability of the catalyst.

The invention relates to a catalyst and a method for preparing p-methyl benzaldehyde from synthesis gas and toluene. The catalyst and the method for preparing p-methyl benzaldehyde from synthesis gasand toluene are characterized in that: a copper-zirconium bimetallic catalyst is used as a main catalyst, and an H-ZMS-5 molecular sieve or an H-ZMS-11 molecular sieve is used as a carrier. The raw material cost is low, one-step preparation method is adopted, the process route is simple and efficient, and the economic advantages are obvious. Cheap synthesis gas is used as the raw material to reactwith toluene, the coupling reaction of an active intermediate for preparing methoxyaldehyde from the synthesis gas and toluene is realized in a gas-phase high-selectivity manner by adopting a fixed bed reactor under the action of the catalyst, and the preparation of high-selectivity p-methyl benzaldehyde is realized in a catalyst pore passage.

The invention belongs to the technical field of petrochemical engineering, and particularly relates to a method for producing an ethylene raw material, which comprises the following steps of: mixing a waste plastic material flow with hydrogen, decolorizing the waste plastic through a fixed bed hydrogenation reactor A filled with a catalyst, and removing metals, sulfur, nitrogen and other impurities to obtain a material flow I; and mixing the material flow I with external hydrogen again, cracking the material flow I through a fixed bed hydrogenation reactor B filled with a catalyst to obtain a material flow II containing an ethylene raw material, and fractionating the material flow II to obtain the ethylene raw material. Waste plastic recycling is achieved, the source of the ethylene raw material is expanded, and the circulation process of the ethylene raw material, ethylene propylene, polyolefin plastic and waste polyolefin plastic is formed.

The invention provides a continuous hydrogenation method of ethyl pyrazine-2-carboxylate. The continuous hydrogenation method comprises the following steps: dispersing a mixture of ethyl pyrazine-2-carboxylate and hydrogen to form a gas-liquid mixture containing small liquid drops with sizes of 50 nm-5 mm, wherein the gas-liquid mixture is used as a reaction raw material; and continuously inputting the reaction raw material into a fixed bed reactor, carrying out a catalytic hydrogenation reaction, and continuously discharging ethyl pyrazine-2-carboxylate, wherein the fixed bed reactor is divided into at least two temperature control sections along the flowing direction of the material, and the temperature of the latter temperature control section is controlled to be lower than the temperature of the former temperature control section. According to the above forced dispersion process, the reaction raw material can be subjected to high-performance mass transfer in the catalytic hydrogenation reaction process, so the sufficient reaction degree of the reaction raw material is improved, and reaction time is shortened. The fixed bed reactor is subjected to sectional temperature controlalong the flowing direction of the material, so heat accumulation can be effectively removed, a reaction state in the reactor can be effectively controlled, and the yield, purity and product performance stability of a target product, namely ethyl pyrazine-2-carboxylate are improved.

The invention discloses a preparation process of an improved sulfur-resistant sintering flue gas decarburization catalyst, which comprises the following steps: adding transition metal salt, phosphoric acid and deionized water into a reactor, heating, stirring and reacting, and stopping stirring after the reaction is finished; cooling, adding titanium dioxide, and continuously heating and stirring; a first reactant is obtained; heating the first reactant, removing the solvent to evaporate the solution to dryness, drying the remainder, putting the remainder into a tubular furnace, introducing inert gas for calcining, and cooling to room temperature; the improved sulfur-resistant sintering flue gas decarburization catalyst is obtained; the improved sulfur-resistant sintering flue gas decarburization catalyst is a CuTiPO catalyst; the obtained improved sulfur-resistant sintering flue gas decarburization catalyst is ground, tableted, sieved and placed in a fixed bed reactor to detect the catalytic performance, the sulfur resistance of the decarburization catalyst is improved, active components are subjected to surface acid modification, the combining capacity of SO2 and the catalyst is inhibited, and the inactivation process of the decarburization catalyst is slowed down.

The invention relates to a fixed-bed pure-oxygen continuous gasification device and process adaptable to diversified coals. According to the device and the process, CO2, pure oxygen and superheated steam serve as gasifying agents and subject to a gasification reaction with feed coal in a fixed-bed pure-oxygen continuous gasifier, so as to generate gasified coal gas; the gasified coal gas enters a dust remover so as to remove solid particles from the gasified coal gas, and a water cooler is arranged at the upper part of the efficient dust remover and is used for recovering part of sensible heat from the gasified coal gas; the gasified coal gas subjected to dust removal enters a heat-pipe heat exchanger for heat recovery, and low-pressure steam is a byproduct; and low-temperature gasified coal gas enters a low-pressure coal gas scrubbing tower for final cooling and dust removal, and scrubbed water gas is connected and conveyed to a gas tank. The content of CO and H2 in the gasified coal gas can reach 80% or more, the ratio range of adjustment of CO among ingredients of the coal gas is 40-65%, the ratio range of adjustment of H2 among the ingredients of the coal gas is 5-40%, and the gasified coal gas can serve as raw material gas of a variety of chemical products through being subjected to further deep treatment by processes such as conversion and purification.