8 results about "Higher alkanes" patented technology

The invention relates to a low-carbon alkane dehydrogenation olefin preparation catalyst, which comprises an alumina carrier and an active component, and is characterized in that the alumina carrier is a millimeter-scale sulfur-containing theta-alumina pellet, the particle size is 1.6-2.5 mm, the specific surface area is 80-150m < 2 > / g, the pore volume is 0.40-0.75 mL / g, the crushing strength is greater than 50N / pellet, the bulk density is 0.55-0.80 g / mL, the length-diameter ratio b / l value is more than 0.95, and the sulfur content is 0.05-0.50%. The theta-alumina pellets are prepared by the following steps: adding an acid solution into an alumina suspension of at least two kinds of hydrated alumina, wherein the acid peptizing index DI of at least one kind of hydrated alumina is 50-85%, peptizing to obtain alumina sol, then dropwise adding the alumina sol into an oil ammonia column through a dropper, pelletizing, drying and roasting. When the catalyst is used for an alkane dehydrogenation reaction, the alkane conversion rate and olefin selectivity are high, and the carbon deposition resistance is strong.

The invention provides a device and a method for producing olefin through negative pressure driven catalysis of alkane dehydrogenation. A reaction unit comprises a pre-lifting zone, an oil agent contact zone, a reaction zone, a product quenching zone, a reaction outlet zone, an oil agent separation zone and a steam stripping zone; the device further comprises a negative pressure driving device, a spent catalyst receiver and a regenerant receiver; an oil-gas outlet of the oil-agent separation zone is communicated with an oil-gas inlet of the negative pressure driving device, and a catalyst outlet of the oil-agent separation zone is communicated with a catalyst inlet of the steam stripping zone; a catalyst outlet of the steam stripping area is communicated with a catalyst inlet of a spent catalyst receiver, and a catalyst outlet of the spent catalyst receiver is communicated with a spent catalyst inlet of the regeneration unit; a regenerated catalyst outlet of the regeneration unit is communicated with a catalyst inlet of a regenerant receiver, and a catalyst outlet of the regenerant receiver is communicated with a catalyst inlet of the oil agent contact area. The alkane dehydrogenation reaction can be carried out under negative pressure, the safety is good, and the alkane conversion rate and the olefin selectivity are high.

The invention provides a device and a method for producing olefin through downward alkane catalytic dehydrogenation. The device comprises a reaction unit and a regeneration unit, the reaction unit sequentially comprises an oil agent contact zone, a reaction zone, an oil agent separation zone and a steam stripping zone from top to bottom; the oil agent contact area is provided with a catalyst distributor and an alkane feeding distributor from top to bottom, and an oil agent contact space is formed between the alkane feeding distributor and the bottom of the oil agent contact area; the reaction zone is a downstream reaction zone; the oil agent separation zone is provided with a reaction oil gas outlet and a catalyst outlet, and the catalyst outlet is communicated with the inlet of the steam stripping zone; the oil agent separation area is provided with a settler and a first two-stage cyclone separator, or is provided with a quick separation device; a spent catalyst outlet of the steam stripping area is communicated with a spent catalyst inlet of the regeneration area, and a regenerated catalyst outlet of the regeneration area is communicated with the catalyst distributor. Based on the device and the method provided by the invention, alkanes are produced into alkenes with high alkane conversion rate and selective dehydrogenation of alkenes.

The invention relates to a molecular sieve morphology regulation and control preparation technology, and aims to provide a method for synthesizing a nanosheet ZSM-23 zeolite molecular sieve by using a double quaternary ammonium base organic template agent. Comprising the following steps: mixing water, a silicon source, an aluminum source, an alkali source and a biquaternary ammonium base organic template agent solution which are used as reaction raw materials, and uniformly stirring to obtain a gel mixture; transferring the gelatinous mixture into a reaction kettle for dynamic crystallization reaction, and centrifuging, washing and drying a reaction product to obtain the zeolite molecular sieve. The molecular structural formula of the bis-quaternary ammonium base organic template agent is shown as a formula I in the specification. According to the invention, the rigid framework is utilized to determine the structure and the flexible tail end adapts to and stabilizes the characteristics of the structure, so that the template agent with higher guiding efficiency is obtained; the molecular sieve synthesized by a hydrothermal single-template method is of a nanoscale sheet structure, has higher alkane conversion rate, monoisomer selectivity and yield, shows better mass transfer efficiency, and is very suitable for long-chain alkane isomerization reaction.

This invention discloses a reactive phase change material composition and its applications. The reactive phase change material composition comprises a higher alkane-based solid-liquid phase change material, an isocyanate, and a long-chain compound, wherein the long-chain compound is a long-chain alcohol and / or a long-chain amine. The reactive phase change material composition provided by this invention can be heated and melted at a relatively low temperature near the phase change temperature, generating a solid-gel phase change material in situ. This avoids the occurrence and leakage of liquid phase change materials and eliminates the cumbersome steps of multi-step purification of small molecule gelling agents. Furthermore, after melting into a liquid state, this reactive phase change material composition can be directly used for the synthesis and re-reaction of phase change emulsions, phase change composite materials, and phase change fibers. During processing, in-situ gelation and solidification are completed to form a solid-gel phase change material, thus avoiding the high temperatures required for heating and liquefying solid-gel phase change materials and a series of problems caused by high temperatures.

The invention belongs to the field of mold cores for aerospace, electronic information, precision investment casting and the like, and particularly relates to a method for solving expansion cracking of a ceramic and refractory metal composite mold core. The method comprises the following steps: (1) calculating according to thermal expansion coefficients of selected refractory metal and a ceramic core ceramic material, and reducing the size of a refractory metal core in equal proportion; (2) the outer surface of the refractory metal mold core is evenly coated with a solid higher alkane substance to prepare a buffer layer, and coating is conducted 1-3 times; (3) the refractory metal mold core is placed at the connecting part of the blade ceramic mold core or the part where the special-shaped hole needs to be reserved; and in the subsequent heating process, the buffer layer is heated, melted and decomposed, and a volume expansion space is provided for the refractory metal mold core. According to the invention, the problem of expansion cracking of the ceramic and refractory metal composite core caused by the expansion coefficient difference between the refractory metal core and the ceramic core is solved, the yield is improved, and the production cost is reduced.

This invention relates to the technical field of photocatalytic carbon chain lengthening, and more particularly to a method for photocatalytic decarboxylation coupling of saturated chain carboxylic acids. Saturated chain carboxylic acids, a photocatalyst, and a solvent are added to a photocatalytic reactor. After replacing the atmosphere in the reactor with an inert gas, the reactor is sealed and stirred until homogeneous. The decarboxylation coupling reaction occurs at 10-40°C under external light irradiation for 1-10 hours. The mass ratio of saturated chain carboxylic acid to solvent is 1:1-50, and the mass ratio of saturated chain carboxylic acid to photocatalyst is 10-100:1. Compared with existing processes, this method has the advantages of low catalyst cost, low energy consumption, fast reaction rate, high selectivity, and no hydrogen consumption. This invention provides a new approach for carboxylic acid cross-coupling reactions and the production of higher alkanes from biomass fatty acids.

The invention relates to a method for preparing olefin from low-carbon alkane, which is characterized in that the low-carbon alkane is contacted with a catalyst comprising an alumina carrier and an active component to carry out dehydrogenation reaction, the preparation method comprises the following steps: adding an acid solution into a turbid liquid of at least two kinds of hydrated alumina, of which the acid peptizing index DI of at least one kind of hydrated alumina is 50-85%, for peptizing to obtain alumina sol, then dropwise adding the alumina sol into an oil ammonia column through a water dropper, balling, drying and roasting to obtain the catalyst, the particle size of the catalyst is 1.6-2.5 mm, the specific surface area is 80-150m < 2 > / g, the pore volume is 0.40-0.75 mL / g, and the pore volume is 0.20-0.75 mL / g. The crushing strength is more than 50N / grain, the bulk density is 0.55-0.80 g / mL, the length-diameter ratio b / l value is more than 0.95, and the sulfur content is 0.05-0.50%. The method is high in alkane conversion rate and olefin selectivity, and the catalyst is high in carbon deposition resistance.