CN106365942B

CN106365942B - Mixed C4 conversion method

Info

Publication number: CN106365942B
Application number: CN201510435645.2A
Authority: CN
Inventors: 孙世林; 李长明; 黄剑锋; 程亮亮; 程琳; 田亮; 张松显; 王玫; 刘飞; 马应海; 王艳飞; 李秋颖; 许江; 景媛媛; 孔祥冰
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2015-07-22
Filing date: 2015-07-22
Publication date: 2020-02-14
Anticipated expiration: 2035-07-22
Also published as: CN106365942A

Abstract

The invention provides a method for preparing a high-octane gasoline component and butadiene from mixed C4, which is a method for producing butadiene and the high-octane gasoline component by mainly carrying out oxidative dehydrogenation, etherification and catalytic dehydrogenation combined processes on the mixed C4 according to the composition characteristics that the contents of n-butane, isobutane and olefin in the mixed C4 are relatively rich. The method has the characteristics of overcoming the defect that diolefins seriously influence the conversion rate of tertiary carbon olefin, the yield of high-octane gasoline and the content of etherification products in the gasoline, producing a certain amount of high-value diolefins as byproducts, and improving the economic benefit and market competitiveness of the process.

Description

Mixed C4 conversion method

Technical Field

The invention relates to a process method for producing butadiene and high-octane gasoline components by mixed C4 conversion.

Background

In the twelfth five year, with the promotion of projects such as 2000 million tons/year oil refining of Guangdong petrochemical of China, 1000 million tons/year oil refining of Kunming, integrative engineering of four-Sichuan petrochemical refining, 80 million tons/year ethylene smoothening petrochemical, 120 million tons/year ethylene reconstruction and expansion of Daqing petrochemical and the like, the oil refining capacity and the ethylene capacity of the China petroleum are further expanded, and the yield of catalytic cracking C4 and cracking C4 resources which are byproducts of a refinery is also greatly increased. The C4 resource is mostly used as civil fuel to burn out except for part of MTBE, alkylate and polymer monomer. And C4 hydrocarbon and topped oil are not only low in price, but also high in transportation cost and large in loss in the transportation process, and belong to low-value products for refineries.

With the rapid development of national economy in China, the automobile holding capacity is continuously increased, and the demand for automobile fuel gasoline is increasingly large. Meanwhile, along with the increasing strictness of the environmental protection requirements on the gasoline quality standard, the quality standard of the motor gasoline is developing towards the direction of low sulfur content, low olefin content, low vapor pressure and high octane number. The market has great demands for increasing the yield of high-quality gasoline and blending components of low-sulfur low-olefin content high-octane gasoline, and the technical development in the aspect also becomes a hot problem concerned by various domestic research units and enterprises.

Butadiene is the main raw material of synthetic rubber, accounts for 71 percent of the total raw material, and the demand of butadiene reaches 350 ten thousand tons in 2015. The source of butadiene in China is single, a carbon four-extraction method is mainly used, the butadiene is produced by an ethylene device, the total resource amount of the butadiene is 284-294 ten thousand tons calculated according to 2100 ten thousand tons of ethylene capacity in 2015, and the butadiene is seriously notched. Another important source of butadiene is the technology of oxidative dehydrogenation of butenes. The butene oxidative dehydrogenation takes normal butene as a raw material, the domestic n-butene dehydrogenation catalyst is subjected to a ternary molybdenum catalyst, a six-membered molybdenum catalyst, an H-198 iron catalyst and a B-O2 iron catalyst under the joint efforts of domestic related units, and a reaction bed is also developed to a subsequent two-stage axial adiabatic fixed bed from an initial guide baffle fluidized bed. The industrial production proves that the combined process of the H-198 iron-based catalyst and the guide baffle fluidized bed and the combined process of the B-O2 iron-based catalyst and the two-section axial adiabatic fixed bed can greatly reduce the production cost and the environmental pollution of the domestic n-butene oxidative dehydrogenation device, and the comprehensive economic benefit reaches the advanced level at the same time.

However, since the 80 th century, with the continuous establishment of large-scale domestic ethylene plants, butadiene production process was gradually replaced by the lower-cost carbon four-extraction method, and many n-butene oxidative dehydrogenation plants were gradually stopped, so that the domestic n-butene oxidative dehydrogenation technology could not be further developed. However, in the long run, due to the influence of the light weight of raw materials of the ethylene cracking device, the new butadiene capacity of the extraction method is more and more difficult to meet the requirement of future downstream synthetic rubber on butadiene. From the production cost, the production cost of butadiene prepared by oxidative dehydrogenation of n-butene is 30-40% higher than that of the traditional extraction method.

On the other hand, with the building and expansion of more and more oil refining devices and ethylene devices, the production capacity of oil refining and ethylene in China is further expanded, and the yield of mixed carbon four resources such as catalytic cracking carbon four and cracking carbon four, which are byproducts of refineries, is also greatly increased. The carbon four resources are mostly used as civil fuel to be burnt except for part of the carbon four resources used for producing MTBE, alkylate, aromatized oil and polymerization monomer. The carbon four resources contain quite abundant n-butene and isobutene except n-butane and isobutane, and are very good raw materials for producing butadiene.

Phillips first developed a two-step n-butane dehydrogenation process to produce butadiene, the first step using a chromium-aluminum catalyst to dehydrogenate n-butane, and the second step further dehydrogenating n-butenes to butadiene in the presence of steam. The raw material of the method is only n-butane, and the method is not suitable for utilizing mixed carbon four generated in oil refining and chemical engineering processes.

In order to improve the product yield of butadiene prepared by dehydrogenating n-butane, BASF company continuously improves on the basis of Phillips two-step method technology, oxygen is added into a second-step dehydrogenation system to combine dehydrogenation reaction and oxidation reaction together, thereby greatly improving the conversion rate of n-butene and the selectivity of butadiene, and the process flow is as follows: a normal butane-containing feedstock is introduced into a first dehydrogenation zone and normal butane is catalytically dehydrogenated non-oxidatively to a first product gas stream of 1-butene, 2-butene and butadiene. The first product gas stream is introduced into a second dehydrogenation zone and 1-butene and 2-butene are oxidatively dehydrogenated to butadiene to produce a second product gas stream comprising butadiene, n-butane, etc., and butadiene is then recovered from the second product gas stream. The non-oxidative catalytic dehydrogenation of n-butane is carried out as autothermal catalytic dehydrogenation in a plate reactor comprising one or more continuous catalyst beds, the dehydrogenation catalyst being a platinum group catalyst. The catalyst for the oxidative dehydrogenation of n-butene to l, 3-butadiene is a molybdenum-bismuth-oxygen multimetal oxide system. Although the product yield of the two-step dehydrogenation process is greatly improved after oxygen is introduced, the process has multiple production steps, high cost and high steam consumption.

The company Snamprogetti SPA, italy, developed DET processes for the etherification of tertiary olefins in light gasolines, using its own tubular and tubular reactor technology, mainly consisting of: light gasoline separating tower, selective hydrogenation reactor, 2 etherification reactors, depentanizer, TAME separating tower, MPP adsorber and non-tertiary olefin skeletal isomerization reactor.

The TAME production process developed by French Petroleum Institute (IFP) includes raw material purification, etherification reaction and methanol recovery 3 parts. Except that the etherification reaction employs a main reactor (expanded bed reactor) and a final reactor (catalytic rectification column) in series, wherein 90% of the total feed is carried out in the expanded bed reactor.

A catalytic light gasoline etherification process developed by the Arco chemical technology company (ARCO) is mainly used for producing MTBE and co-producing TAME. The etherification reaction in the light gasoline etherification process adopts a series fixed bed adiabatic reactor. The technological process includes 3 unit processes of material purification, etherification reaction and methanol recovery. The C5 raw material is mixed with methanol after being washed and pretreated by selective hydrogenation, enters two fixed bed adiabatic reactors connected in series and reacts under the action of an ion exchange resin catalyst.

In the process of producing butadiene by using the two-step dehydrogenation method, n-butene and n-butane mainly contribute, and the conversion rate of isobutene and isobutane is lower. And in the catalytic dehydrogenation process, the conversion rate of converting isobutane into isobutene is high. The etherification technology can be used for converting tertiary carbon olefin in the material flow into corresponding ether compounds under the action of the catalyst, the conversion rate of the tertiary carbon olefin is over 95 percent, and isobutene is converted into the ether compounds with high octane number to be used as gasoline blending components. Different from n-butene and n-butane raw materials, the mixed C4 contains rich n-butane and also contains n-butene, isobutene and isobutane with equivalent content.

Disclosure of Invention

The invention aims to provide a method for producing butadiene and high-octane gasoline components by using mixed C4 through a process of combining oxidative dehydrogenation, etherification and catalytic dehydrogenation aiming at the composition characteristic that the mixed C4 contains relatively rich n-isobutane and n-isoolefin.

A mixed C-C conversion method is characterized in that the conversion process at least comprises the following steps: the first step, mixing a carbon four raw material, a material flow containing an oxidant and water or steam, feeding the mixture into an oxidative dehydrogenation unit, reacting in a reactor filled with an oxidative dehydrogenation catalyst, feeding the mixture into a separation unit I, and separating the reacted material flow into butadiene, other carbon four fractions and other components; secondly, sending other carbon four fractions separated in the first step and alcohol material flows into an etherification unit, carrying out etherification reaction in a reactor filled with an etherification catalyst, sending reaction products into a separation unit II, and separating the material flows after the reaction into more than five carbon components, carbon four hydrocarbons and other components; and thirdly, the carbon tetrahydrocarbon and the hydrogen separated in the second step are sent into a catalytic dehydrogenation unit, alkane catalytic dehydrogenation reaction is carried out in a reactor filled with a catalytic dehydrogenation catalyst, non-condensable gas is separated from the material flow after catalytic dehydrogenation through a separation unit III, and the material flow and the mixed carbon tetrahydrocarbon raw material are sent into an oxidative dehydrogenation unit together.

In the invention, the mixed C-C raw material refers to C-C hydrocarbons generated in oil refining and chemical engineering processes, such as C-C, C-C. Wherein the mass content of the C-tetrahydrocarbon is not less than 95%, preferably not less than 99%, the mass content of the C-tetraolefin is not less than 40%, preferably not less than 50%, and the mass content of the n-butene and the n-butane is not less than 35%, preferably not less than 40%. Can be raw materials from the same source or can be mixed with raw materials from different sources.

The catalyst of the oxidative dehydrogenation unit of the invention is not particularly required, and can meet the requirements that the conversion rate of n-butene is not less than 70%, preferably not less than 75%, the percentages which are not particularly specified in the invention are mass%, the oxidative dehydrogenation catalyst can be prepared by using some high-temperature-resistant framework materials to load a main active component and an auxiliary active component in a specific ratio, wherein the high-temperature-resistant framework structure can be a metal wire mesh, a porous monolith or alumina, silica, zirconia, cordierite, titanium oxide, mullite, stable alumina, stable zirconia and the like in different shapes, or a mixture of two or more of the above high-temperature-resistant materials, the loading mode of the active components can be a micro-wet impregnation method, a chemical vapor deposition method, a coprecipitation method and the like, the main active component can be a lanthanide series metal element or oxide of a metal element in a range of 3% to 8%, or a mixture of the above substances, specifically can be samarium, cerium, praseodymium, terbium and the oxide thereof, or a combination of one or several of the above substances, or a combination of a platinum series metal element and ruthenium in a platinum series oxide, a ruthenium, a specific combination of platinum series metal element in a platinum series, a platinum series oxide, a platinum, a lanthanum, a platinum.

The reaction conditions of the oxidative dehydrogenation unit in the present invention are slightly different depending on the catalyst, but it is preferable that: the temperature is 280-410 ℃, preferably 310-395 ℃, the pressure is 0-100 KPa, preferably 0-40 KPa, and the volume space velocity is 10-500 h^-1Preferably 60 to 400 hours^-1. The space velocities not specifically described in the present invention are all liquid hourly volume space velocities.

The stream containing the oxidant in the oxidative dehydrogenation unit of the present invention may be a stream containing oxygen molecules or strongly oxidizing oxygen atoms such as oxygen, oxygen-rich gas, air, etc., with air, oxygen-rich gas and oxygen being preferred in the present invention. Oxygen-rich gas is particularly preferred. Oxygen-enriched gas with an oxygen content of between 32% and 45% is particularly recommended. Wherein the molar ratio of oxygen to olefin in all hydrocarbon materials entering the oxidative dehydrogenation unit is 0.1-1.0: 1, preferably 0.3-0.85: 1, calculated as oxygen in the stream containing the oxidant. During the feeding process of the oxidative dehydrogenation unit, water or steam is added in a certain ratio to prevent the problems of catalyst coking and over-quick temperature rise of a catalyst bed layer caused by coking. The mass ratio of all hydrocarbon materials in the water or steam oxidative dehydrogenation unit can be 0.5-30: 1, and preferably 5-20: 1.

The reactor of the oxidative dehydrogenation unit can be a fixed bed reactor, a fluidized bed reactor, a moving bed reactor and a trickle bed reactor, can also be a catalytic rectification reactor and a fixed bed reaction tube bundle, and can also be connected in series and/or in parallel. The preferable reactor is a parallel connection mode of two or more fixed bed reactors or fluidized bed reactors, so that the regeneration of the catalyst and the continuity of the technological process are facilitated.

The separation method in the separation unit I can be extraction, rectification, extractive rectification, azeotropic rectification, membrane separation, chemical absorption and the like. More technically sophisticated separation techniques may be used to obtain an acceptable 1, 3-butadiene product and to obtain a butadiene content in the other carbon four fractions separated of no more than 0.3%, preferably no more than 0.1%.

In the etherification unit of the present invention, the etherification catalyst is not particularly limited, and the conversion of isobutylene is required to be not less than 95%.

The alcohol material flow in the etherification unit in the invention refers to a low-carbon alcohol with the carbon atom number not more than 4, and particularly, methanol and ethanol are recommended, and methanol is preferred.

When the raw materials enter the etherification reaction unit, the molar ratio of the alcohols to the isobutene in all hydrocarbon materials entering the etherification unit is 0.8-1.5: 1, preferably 1.1-1.3: 1.

The reaction conditions of the etherification unit in the invention are as follows: 30-100 ℃, preferably 45-80 ℃, the pressure is 0.1-2.0 MPa, preferably 0.5-1.5 MPa, and the volume space velocity is 0.1-5 h^-1Preferably 1 to 2 hours^-1。

The etherification reactor in the present invention is not particularly limited, and may be one or a combination of several of a fixed bed, a moving bed suspension bed, a catalytic distillation reactor, and the like. But the catalytic distillation technology is best, tertiary carbon olefin can be fully converted, the carbon four fraction produced at the top of the methanol removing tower in the separation unit is sent to the catalytic dehydrogenation unit, the gasoline component with high octane number is produced at the bottom of the tower, and the recovered methanol can also be recycled to the inlet of the etherification reactor for use.

In the separation unit II of the present invention, the separation method is not limited, and may be rectification, extraction, membrane separation, etc., but rectification is more preferably used. The mass content of the carbon four component in the carbon four material flow for separating the ether is not less than 97 percent, and preferably not less than 99 percent.

The dehydrogenation catalyst is not particularly limited in the catalytic dehydrogenation unit of the present invention, and the olefin content in the catalytic dehydrogenation product is required to be not less than 35%, preferably to be not less than 45%.

The reaction conditions of the catalytic dehydrogenation unit of the present invention are preferably: 480-700 ℃, the pressure of 0.01-3 MPa and the liquid volume space velocity of 0.1-10 h^-1. Particularly preferred reaction conditions are: 560-650 ℃, 0.4-1.2 MPa of pressure and 2-7 h of liquid volume airspeed^-1。

The molar ratio of hydrogen to carbon tetrahydrocarbon entering the catalytic dehydrogenation unit is 0.01-1: 1, and preferably 0.1-0.5: 1.

The catalytic dehydrogenation reactor involved in the invention is a fixed bed reactor, can be a reactor which is used independently and intermittently realized through two processes of reaction-catalyst regeneration, can also be used in parallel for cyclic operation by two or more reactors, and can also be used in parallel and/or in series combination by a plurality of reactors. When the catalyst in one or more reactors is seriously inactivated due to carbon deposition, the inactivated catalyst is recycled after regeneration by switching the material inlet and the material outlet, and the continuous operation of a reaction and regeneration system is realized.

In the invention, the non-condensable gas after the catalytic dehydrogenation unit and the dry gas separated by the separation unit II can be directly recycled to the material inlet of the catalytic dehydrogenation unit for recycling.

In addition, the separation unit may include a separation device for non-condensable gas, such as a flash drum, an absorption/desorption tower, a cooling device, a compression device, and the like.

Hair brushMore specific embodiments are as follows: the mixed C-C raw material is used, wherein the mass content of the C-C is not less than 95%, preferably not less than 99%, the mass content of the C-C. The temperature is 280-410 ℃, the pressure is 0-100 KPa, and the volume space velocity is 10-500 h^-1Mixing the mixture with oxygen-enriched air flow with the oxygen content of 32-45% to perform oxidative dehydrogenation reaction under the process condition that the molar ratio of oxygen to all hydrocarbon materials entering an oxidative dehydrogenation unit is 0.1-1: 1, the mass ratio of water or water vapor to all hydrocarbon materials entering the oxidative dehydrogenation unit is 0.5-30: 1, separating butadiene from reaction products, and then feeding the butadiene and alcohol material flow into an etherification unit, wherein the molar ratio of alcohol to isobutene in the hydrocarbon materials entering the etherification reactor is 0.8-1.5: 1, preferably 1.1-1.3: 1, the reaction product is heated at 30-100 ℃, preferably 45-80 ℃, the pressure is 0.1-2.0 MPa, preferably 0.5-1.5 MPa, and the volume space velocity is 0.1-5 h^-1Preferably 1 to 2 hours^-1After the etherification reaction is carried out under the condition, ether compounds and other components in reaction products are separated, the residual carbon tetrahydrocarbon enters a catalytic dehydrogenation unit, the temperature is 480-700 ℃, the pressure is 0.01-3 MPa, and the volume space velocity is 0.1-10 h^-1And after the hydrogen and all hydrocarbon materials entering the catalytic dehydrogenation unit are subjected to catalytic dehydrogenation reaction under the condition that the molar ratio of the hydrogen to all hydrocarbon materials entering the catalytic dehydrogenation unit is 0.01-1: 1, the hydrogen and the raw material mixed carbon four enter the oxidative dehydrogenation unit together.

The invention has the advantages that in the process of modifying and utilizing the mixed carbon four, the defects of unfriendly environment in the production process of the isomerization technology, high dry gas generation rate of the high-temperature aromatization technology which is always 20 percent, small loss on the economic benefit of the process and the like are overcome, in the process of continuously and deeply researching and utilizing the etherification technology, a diene unit and a diene separation unit are produced by adding oxidative dehydrogenation, the conversion rate of monoolefine etherification and the yield of ether compounds are greatly influenced by the diene, and meanwhile, a certain amount of high-value diene is by-produced, so that the economic benefit and market competitiveness of the process are improved, and another process is provided for more finely utilizing the low-carbon alkane. In addition, during the oxidative dehydrogenation, small amounts of ketones and aldehydes are produced due to the occurrence of side reactions. While the amount of aldehydes and ketones produced is too high, which directly affects the selectivity of diolefins, the process of treating the wastewater produced by washing aldehydes and ketones also increases the cost of the process. In the invention, the total amount of the materials entering the reaction system is controlled by controlling the oxygen content in the oxygen-enriched airflow, so as to control the contact of oxygen atoms and olefin in the reaction system and the catalyst, and control the reaction residence time on the other hand. The method not only can ensure that the monoolefine is fully converted into the dialkene, but also can effectively control the generation of alcohols and aldehydes, and improve the yield and the selectivity of the dialkene.

Drawings

FIG. 1 is a schematic view of a process flow for applying the present invention.

In the figure: r1-oxidative dehydrogenation reactor, R2-etherification reactor, R3-catalytic dehydrogenation reactor, T1, T2 and T3-separation systems I, II and III behind the reactors R1, R2 and R3.

Detailed Description

The present invention is described in detail below by way of examples. Tables 1 and 2 show properties of the mixed carbon four raw material used in the examples, mixed carbon four a is catalytic shop mixed carbon four of lanzhou petrochemical company, and mixed carbon four B is one-heavy catalytic mixed carbon four of daqing refinery company. The methanol is the methanol produced by Cangzhou Zhengyuan chemical industry limited company, wherein the mass content of the methanol is 99.5 percent. The ethanol is anhydrous ethanol produced by autumn cloud chemical limited company in Yixing city, wherein the mass content of the ethanol is 99.5%.

TABLE 1 composition of C-C.sub.four A (W%)

TABLE 2 composition of C-C B mixture (W%)

Components	ω％	Components	ω％
				Propane	0.00	Isobutene	12.45
Propylene (PA)	0.00	Cis-butene-2	12.79
				Isobutane	34.29	Isopentane	0.06
N-butane	10.38	1, 3-butadiene	0.07
				Trans-butene-2	17.33	2-methyl-2-butene	0.02
1-butene	12.63	1-pentene	0.04

The example adopts the process shown in figure 1, the catalytic dehydrogenation reactor in the example is a 200ml pressurized fixed bed reactor, two reactors are recycled, the oxidative dehydrogenation unit adopts a 100ml suspended bed reactor, the etherification reaction system adopts a catalytic distillation reaction device, the pre-etherification reactor is a 200ml fixed bed, and the catalyst loading in the reactive distillation tower is 150 ml. The samples analyzed were transient samples after 3 hours of reaction. A rectification column having a theoretical plate number of 18 was used in separation unit I (T1). And (3) dehydrating in a separation unit II (T2) by adopting a cyclone separator, removing non-condensable gas by flash evaporation, and separating the dialkene by an extraction method. The separation unit III (T3) used a rectification column with a theoretical plate number of 10.

In the raw materials used for preparing the catalyst in the examples, sesbania powder is of industrial grade, and the others are all commercially available chemical pure reagents.

The water is deionized distilled water.

The oxygen-enriched air flow is prepared by mixing industrial-grade pure oxygen and air.

In the examples, the methods for calculating the olefin content, the diene yield, the aromatization product yield and the aromatic hydrocarbon content are as follows:

olefin content (mass of butenes and pentenes produced in the catalytic dehydrogenation product/mass of all hydrocarbons in the catalytic dehydrogenation product) 100

Mass yield of alcohols-mass of alcohols produced in the oxydehydrogenation unit and/or mass of hydrocarbon feed to the oxydehydrogenation unit-100

Mass yield of ketones (mass of ketones produced in the oxydehydrogenation unit and/or mass of hydrocarbon feed to the oxydehydrogenation unit) 100

The mass yield of diolefins (mass of diolefins produced in the oxydehydrogenation unit/mass of hydrocarbon feedstock entering the oxydehydrogenation unit) 100

Yield of etherification product (mass of all products after removal of non-condensable gas/mass of hydrocarbon material entering etherification unit 100

Example 1

The olefin oxidative dehydrogenation catalyst is prepared by adopting the preparation method of example 2 in patent CN102671714A, and the preparation method comprises the following steps: 17 g of magnesium nitrate hexahydrate was dissolved in 20ml of distilled water, 20 g of zirconia was then added, and after the above mixed solution was subjected to evaporation drying at 80 ℃ for 12 hours, the resulting solid sample was heated in a muffle furnace in an air atmosphere at 550 ℃ for 3 hours, and then the sample was impregnated with an aqueous solution of ammonium metavanadate. An aqueous solution of ammonium metavanadate was prepared by dissolving 5g of ammonium metavanadate and 10.6 g of oxalic acid in a small amount of distilled water. Drying a sample soaked by the ammonium metavanadate solution at 80 ℃ for 12 hours, then heating the obtained solid sample in a muffle furnace at 550 ℃ in an air atmosphere for 3 hours, and finally sieving the solid sample into 40-80 meshes for later use. The etherification catalyst adopts KC-116 type resin catalyst produced by Kery chemical company, the particle size range is more than or equal to 99 percent (0.355-1.250 mm), the wet density is 1150-1250 g/l, and the total exchange capacity is more than or equal to 1.7mmol/ml [ H ]⁺]The mechanical strength is more than or equal to 98 percent (H type). The catalytic dehydrogenation catalyst is HTPB-DH dehydrogenation catalyst of Haitai company, wherein Al is used₂O₃Pt and Cl are used as active components as a carrier, wherein the mass content of Pt is 1%, the mass content of chlorine is 2%, and the specific surface area is 200m²G, pore volume of 0.5ml/g, diameter of 1.59mm, bulk density of 0.6g/cm³. The raw material A, air and water are preheated and enter an oxidative dehydrogenation reactor, and the temperature, the atmospheric pressure and the space velocity are respectively 340 h^-1The olefin oxygen in all hydrocarbon materials entering the oxidative deoxidation unit is 1:0.68 (molar ratio), and the olefin water in all hydrocarbon materials entering the oxidative dehydrogenation unit is 1:12 (mass ratio). In the reaction product, the mass yield of diolefin was 55.4%, the mass yield of alcohols was 0.52%, and the mass yield of ketones was 0.45%. After butadiene is separated from the reaction product by a separation unit I, other four-carbon fractions enter an etherification reactor, and the reaction conditions of etherification are as follows: the reaction temperature is 45 ℃, and the volume space velocity is 2h^-1The reaction pressure is 1.5MPa, wherein the molar ratio of the methanol to the isobutene in the hydrocarbon material entering the etherification reactor is 1.2: 1. Reaction productIn the above, the mass yield of the ether compound was 49.2%. After ether compounds are separated by the separation unit II, the carbon-tetrahydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering the catalytic deoxidation unit is 0.25:1, the reaction temperature is 480 ℃, and the volume space velocity is 0.1h^-1And carrying out catalytic dehydrogenation under the reaction pressure of 0.01MPa, wherein the olefin content in the dehydrogenation product is 37.1%.

Example 2

The olefin oxidative dehydrogenation catalyst adopts the preparation method of the catalyst in the patent CN99106660.X in the example 1, and the specific preparation method is as follows: stirring and heating 43.5g of manganese dioxide powder and 1000ml of water in the same container for 10 minutes, then adding 1.09 g of antimony trioxide powder, heating the system to 80 ℃, stirring for 2 hours, then heating the system to 90 ℃, stirring for 4 hours again, drying the system to form paste at 120 ℃ for 14 hours, preparing powder, molding, and finally sieving to 40-80 meshes for later use. The etherification catalyst is D005-II resin catalyst produced by Dandong Mingzhu Special resin Co. The particle size range is 0.315-1.25mm, the wet density is 1180-1200 g/l, and the total exchange capacity is more than or equal to 5.2mmol/g [ H ]⁺]The mechanical strength is more than or equal to 95 percent (H type). The catalytic dehydrogenation catalyst was prepared using the method of example 4 in CN 101940922A. The method comprises the following specific steps: 117.5 g of chromium oxide is weighed and dissolved in deionized water to be fully stirred to prepare a chromium oxide solution with the weight concentration of 47 percent. Then, an aqueous solution of potassium nitrate with a weight concentration of 3.86% was prepared. Then 55.0 g of pseudo-boehmite, 2.2 g of bentonite and 7.59 g of prepared chromium oxide solution are fully mixed, kneaded and extruded into pellets. Then dried at 120 ℃ for 3 hours, then thermostated at 500 ℃ for 3 hours, at 620 ℃ for 2 hours, and finally calcined at 760 ℃ for 4 hours in 20% water and 80% air. And taking 11.39 g of prepared chromium oxide solution, soaking the roasted sample for 20 minutes, drying at 120 ℃ for 3 hours, and roasting at 550 ℃ for 5 hours. Soaking in prepared potassium nitrate water solution, drying at 120 deg.C for 3 hr, and calcining at 620 deg.C for 6 hr. Preheating raw material B, oxygen-enriched air flow containing 45% of oxygen and water, feeding the preheated raw material B, oxygen-enriched air flow and water into an oxidative dehydrogenation reactor, and controlling the temperature at 350 ℃, the pressure at 100KPa and the volume space velocity at 10h^-1The olefin and oxygen in the hydrocarbon material entering the oxidation unit are 1:0.3 (molar ratio), and the hydrocarbon material and water entering the oxidation unit are 1:30 (mass ratio). In the reaction product, the mass yield of diolefin was 49.2%, the mass yield of alcohols was 0.47%, and the mass yield of ketones was 0.23%. The reaction product passes through a separation unit I to separate butadiene, and other four-carbon fractions enter an etherification reactor, wherein the reaction conditions of etherification are as follows: the reaction temperature is 80 ℃, and the volume space velocity is 3.0h^-1The reaction pressure is 1.0MPa, wherein the molar ratio of the methanol to the isobutene in the hydrocarbon material entering the etherification reactor is 1.1: 1. In the reaction product, the mass yield of the ether compound was 44.8%. After ether compounds are separated by the separation unit II, the carbon-tetrahydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering the catalytic deoxidation unit is 0.1:1, the reaction temperature is 700 ℃, and the volume space velocity is 1.0h^-1And reacting at the reaction pressure of 0.15MPa to obtain the dehydrogenation product with the olefin content of 51.6 percent.

Example 3

The olefin oxidative dehydrogenation catalyst is prepared by adopting the method of preparation example 2 in patent 200780013916.9, and comprises the following specific steps: 69 g of ammonium molybdate is dissolved in 500ml of distilled water and stirred, then 108.1 g of bismuth nitrate is added into 5.3 percent nitric acid solution and stirred until the bismuth nitrate is completely dissolved, and then the solution is dripped into the ammonium molybdate solution. Then, ammonia water is dripped to enable the pH value of the solution to be 1.5, the solution is stirred for 1 hour, a solid sample is obtained through decompression and suction filtration, the solid sample is dried for 26 hours at the temperature of 100 ℃, then calcined for 24 hours at the temperature of 475 ℃ in a muffle furnace, and finally the solid sample is crushed and sieved into 20-80 meshes for later use. The etherification catalyst adopts NKC-9 cation exchange resin catalyst produced by the chemical plant of southern Kai university. The particle size range is more than or equal to 95 percent (0.4-1.25 mm), and the specific surface area is 77m²G, pore volume of 0.27ml/g, total exchange capacity of not less than 4.7mmol/g [ H ]⁺]. The dehydrogenation catalyst was prepared by the method of example 1 of patent CN 101618319. Dissolving 2.24 g of calcium oxide and 3.1 g of polyethylene glycol in 120ml of deionized water, carrying out hydrothermal treatment at 240 ℃ for 24 hours, burning at 600 ℃ for 5 hours, and mixing with a proper amount of absolute ethyl alcohol, 7.2 g of chromium nitrate and 6g of aluminum oxideUniformly grinding the mixture after drying for twelve hours, and burning the mixture for 3 hours at 550 ℃ for later use. Preheating the oxygen-enriched gas flow containing 35% of oxygen and water, feeding the oxygen-enriched gas flow and water into an oxidative dehydrogenation reactor, and controlling the temperature at 380 ℃ and the volume space velocity at 50KPa for 60h^-1The olefin and oxygen in the hydrocarbon material entering the oxidation unit are 1:0.1 (molar ratio), and the hydrocarbon material and water entering the oxidation unit are 1:5 (mass ratio). In the reaction product, the mass yield of diolefin was 56.1%, the mass yield of alcohols was 0.39%, and the mass yield of ketones was 0.18%. The reaction product passes through a separation unit I to separate butadiene, and other four carbon components enter an etherification reactor, wherein the reaction conditions of the etherification are as follows: the reaction temperature is 65 ℃, and the volume space velocity is 4h^-1The reaction pressure is 0.5MPa, wherein the molar ratio of the methanol to the isobutene in the hydrocarbon material entering the etherification reactor is 1.3: 1. In the reaction product, the mass yield of the ether compound was 58.8%. After ether compounds are separated by the separation unit II, the carbon-tetrahydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering the catalytic deoxidation unit is 0.01:1, the reaction temperature is 570 ℃, and the volume space velocity is 3.0h^-1And reacting under the condition that the reaction pressure is 1.7MPa, wherein the olefin content in the dehydrogenation product is 54.9%.

Example 4

The olefin oxidative dehydrogenation catalyst is prepared by adopting the method of preparation example 2 in patent 200880014941.3, and comprises the following specific steps: dissolving 14.2 g of zinc chloride and 56.1 g of ferric chloride hexahydrate in 800ml of distilled water, fully stirring until the zinc chloride and the ferric chloride are completely dissolved, dropwise adding a 3M sodium hydroxide aqueous solution to adjust the pH value of the solution to 8, stirring at room temperature for 12 hours, and then carrying out vacuum filtration to obtain a solid sample. And drying the solid sample at 175 ℃ for 16 hours, calcining at 650 ℃ for 12 hours, and finally crushing and screening into 20-65 meshes for later use. The etherification catalyst is macroporous strong acid resin catalyst produced by Jiangsu Oko petrochemical technology limited company, the particle size is 0.315-1.25mm, the bulk density is 0.77-0.85g/ml, and the specific surface area is more than 20-70m²Per g, pore diameter is more than 20-50nm, and pore volume is more than 0.3-0.5 cc/g. The dehydrogenation catalyst was prepared using the method of example 4 in CN 101940922A. The specific steps are: 117.5 g of chromium oxide is weighed and dissolved in deionized water to be fully stirred to prepare a chromium oxide solution with the weight concentration of 47 percent. Then, an aqueous solution of potassium nitrate with a weight concentration of 3.86% was prepared. Then 55.0 g of pseudo-boehmite, 2.2 g of bentonite and 7.59 g of prepared chromium oxide solution are fully mixed, kneaded and extruded into pellets. Then dried at 120 ℃ for 3 hours, then thermostated at 500 ℃ for 3 hours, at 620 ℃ for 2 hours, and finally calcined at 760 ℃ for 4 hours in 20% water and 80% air. And taking 11.39 g of prepared chromium oxide solution, soaking the roasted sample for 20 minutes, drying at 120 ℃ for 3 hours, and roasting at 550 ℃ for 5 hours. Soaking in prepared potassium nitrate water solution, drying at 120 deg.C for 3 hr, and calcining at 620 deg.C for 6 hr. Preheating raw material B, oxygen-enriched air flow containing 40% of oxygen and water, feeding the preheated raw material B, oxygen-enriched air flow and water into an oxidative dehydrogenation reactor, and controlling the temperature at 390 ℃, the pressure at 20KPa and the volume space velocity at 500h^-1The olefin and oxygen in the hydrocarbon material entering the oxidation unit are 1:0.8 (molar ratio), and the hydrocarbon material and water entering the oxidation unit are 1:16 (mass ratio). In the reaction product, the mass yield of diolefin was 46.7%, the mass yield of alcohols was 0.41%, and the mass yield of ketones was 0.20%. The reaction product passes through a separation unit I to separate butadiene, and other four-carbon fractions enter an etherification reactor, wherein the reaction conditions of etherification are as follows: the reaction temperature is 75 ℃, and the volume space velocity is 5h^-1The reaction pressure is 1.2MPa, wherein the molar ratio of the methanol to the isobutene in the hydrocarbon material entering the etherification reactor is 1.5: 1. In the reaction product, the mass yield of the ether compound was 50.5%. After ether compounds are separated by the separation unit II, the carbon-tetrahydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering the catalytic deoxidation unit is 0.3:1, the reaction temperature is 600 ℃, and the volume space velocity is 5.0h^-1And reacting under the reaction pressure of 1.1MPa to obtain a dehydrogenation product with the olefin content of 64.0 percent.

Example 5

The olefin oxidative dehydrogenation catalyst is prepared by adopting the method in CN96113127 and the method in example 4, and comprises the following specific steps: 177 g Fe (NO)₃)₃·9H₂O, 43.3 g Zn (NO)₃)₂·6H₂O, 43 g Ca (NO)₃)₂·4H₂O, 1.5 g Co (NO)₃)₂·6H₂Dissolving O in 500ml of distilled water, dropping 20% ammonia water for precipitation under rapid stirring, and adding 1g of sesbania powder in the precipitation process. When the pH value of the solution is 8.5, the ammonia water dropping is finished. The precipitate was heat-aged at 80 ℃ for 1 hour, at 55 ℃ for 30 minutes, filtered and washed twice with 1000ml of water each time. And drying the filter cake at 110 ℃ for 12 hours, calcining at 650 ℃ for 14 hours, and finally screening to obtain the filter cake with the size of 40-80 meshes for later use. The etherification catalyst is an etherification resin catalyst produced by Kery chemical Co., Ltd, the particle size range of the etherification resin catalyst is 0.335-1.25 mm, the wet density is 0.75-0.85 g/ml, the total exchange capacity is more than or equal to 5.2mmol/g, and the mechanical strength is more than or equal to 95%. The dehydrogenation catalyst was prepared by the method of example 9 of patent No. cn96121452. x. Weighing 17 g Cr (NO)₃)₃·9H₂O, 1.1 g Cu (NO)₃)₂·3H₂O, 80.8 g Al (NO)₃)₃·9H₂And O, preparing the catalyst by using a coprecipitation method, wherein a 10% KOH (or NaOH) solution is selected as a precipitator, nitrate is dissolved in distilled water, the precipitator is added while stirring to completely form gel, the pH value is 8.5-9, the aging is carried out for 3 hours, the filtering is carried out, the drying is carried out for 20 hours at the temperature of 110 ℃, the roasting is carried out for 7 hours at the temperature of 650 ℃, and the catalyst is crushed and screened for later use. Preheating raw material A, oxygen-enriched airflow containing 32% of oxygen and water, feeding the preheated raw material A, the oxygen-enriched airflow and the water into an oxidative dehydrogenation reactor, and controlling the temperature at 280 ℃, the pressure at 10KPa and the volume space velocity at 300h^-1The olefin and oxygen in the hydrocarbon material entering the oxidation unit are 1:0.55 (molar ratio), and the hydrocarbon material and water entering the oxidation unit are 1:10 (mass ratio). In the reaction product, the mass yield of diolefin was 55.6%, the mass yield of alcohols was 0.43%, and the mass yield of ketones was 0.21%. After butadiene is separated from the reaction product by a separation unit I, other four-carbon fractions enter an etherification reactor, and the reaction conditions of etherification are as follows: the reaction temperature is 55 ℃, and the volume space velocity is 0.1h^-1The reaction pressure is 2.0MPa, wherein the molar ratio of the ethanol to the isobutene in the hydrocarbon material entering the etherification reactor is 1.2: 1. In the reaction product, the mass yield of the ether compound was 48.5%. After the ether compound is separated out by the separation unit II,the four-carbon hydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering a catalytic deoxidation unit is 0.15:1, the reaction temperature is 650 ℃, and the volume space velocity is 8.0h^-1And reacting under the condition that the reaction pressure is 2.4MPa, wherein the olefin content in the dehydrogenation product is 35.6%.

Example 6

The olefin oxidative dehydrogenation catalyst is prepared by adopting the preparation method of the example 1 in the patent CN103055890, and comprises the following specific steps: firstly, 280 g of iron powder and 80.3 g of zinc powder are added into 1000ml of 1M nitric acid solution, 97.1 g of manganese nitrate and 3.3 g of magnesium nitrate are added after complete dissolution, 20% ammonia water is added dropwise and fully stirred at the solution temperature of 60 ℃ until the pH value is 7.5, the solution temperature is kept at 60 ℃, stirring and aging are continued for 60 minutes, slurry is filtered and washed until the pH value is 7.0-9.0, then a filter cake is extruded into strips, dried at 200 ℃ for 12 hours, and the strips are chopped into 2-3 mm for standby after being calcined at 500 ℃ for 48 hours. Etherification catalyst RZE-3 zeolite etherification catalyst developed by petrochemical academy of sciences was purchased, the appearance was spherical with a diameter of 8mm and the bulk density was 0.71g/cm³Specific surface area 487m²Per g, pore volume of 0.464mL/g, average pore diameter of 175nm, intensity>20N, and (3). Dehydrogenation catalyst the catalyst was prepared using the procedure for the catalyst preparation of example 1 of patent CN 101623633 a. Firstly, ZSM-5 molecular sieve raw powder is put in 0.16M SnCl₂·2H₂The O solution was immersed at 80 ℃ for 10hr so that the Sn loading in the catalyst reached 4 wt%, and then dried at 120 ℃ for 6 hr. The dried sample was calcined at 550 ℃ for 4hr in an air atmosphere. The calcined powder was at 0.03M H₂PtCl₆·6H₂Soaking in O solution at 80 deg.C for 4hr to obtain catalyst with Pt content of 20 wt%, drying at 120 deg.C for 6hr, and calcining at 550 deg.C for 4 hr. Then reducing with hydrogen at 550 deg.C for 12 hr. Preheating with pure oxygen and water, introducing into an oxidative dehydrogenation reactor at 340 deg.C, 70KPa, and volume space velocity of 250h^-1The olefin and oxygen in the hydrocarbon material entering the oxidation unit are 1:0.1 (molar ratio), and the hydrocarbon material and water entering the oxidation unit are 1:0.5 (mass ratio). Reaction productIn the product, the mass yield of diolefins was 41.7%, the mass yield of alcohols was 0.82%, and the mass yield of ketones was 0.66%. The reaction product passes through a separation unit I to separate butadiene, and other four carbon components enter an etherification reactor, wherein the etherification reaction conditions are as follows: the reaction temperature is 30 ℃, and the volume space velocity is 0.5h^-1The reaction pressure is 1.7MPa, wherein the molar ratio of the methanol to the isobutene in the hydrocarbon material entering the etherification reactor is 0.95: 1. In the reaction product, the mass yield of the ether compound was 42.5%. After ether compounds are separated by the separation unit II, the carbon-tetrahydrocarbon enters a catalytic dehydrogenation reactor, the molar ratio of hydrogen to all hydrocarbon materials entering the catalytic deoxidation unit is 0.5:1, the reaction temperature is 550 ℃, and the volume space velocity is 10.0h^-1And reacting under the condition that the reaction pressure is 3.0MPa, wherein the olefin content in the dehydrogenation product is 44.7%.

Comparative example

Etherification catalyst RZE-3 zeolite etherification catalyst developed by petrochemical academy of sciences was purchased, the appearance was spherical with a diameter of 8mm and the bulk density was 0.71g/cm³Specific surface area 487m²Per g, pore volume of 0.464mL/g, average pore diameter of 175nm, intensity>20N, and (3). Dehydrogenation catalyst the catalyst was prepared using the procedure for the catalyst preparation of example 1 of patent CN 101623633 a. Firstly, ZSM-5 molecular sieve raw powder is put in 0.16M SnCl₂·2H₂The O solution was immersed at 80 ℃ for 10hr so that the Sn loading in the catalyst reached 4 wt%, and then dried at 120 ℃ for 6 hr. The dried sample was calcined at 550 ℃ for 4hr in an air atmosphere. The calcined powder was at 0.03M H₂PtCl₆·6H₂Soaking in O solution at 80 deg.C for 4hr to obtain catalyst with Pt content of 20 wt%, drying at 120 deg.C for 6hr, and calcining at 550 deg.C for 4 hr. Then reducing with hydrogen at 550 deg.C for 12 hr. Mixing the raw material B with methanol, and feeding the mixture into an etherification reactor, wherein the etherification reaction conditions are as follows: the reaction temperature is 73 ℃, and the volume space velocity is 1.4h^-1The reaction pressure is 1.7MPa, wherein the molar ratio of the methanol to the isobutane in the hydrocarbon material entering the etherification reactor is 0.95: 1. The ether compound was isolated via a separation unit with a yield of 34.1%. Hydrogen in dehydrogenation reactor and all hydrocarbon materials entering catalytic deoxidation unitThe molar ratio is 0.5:1, the reaction temperature is 550 ℃, and the volume space velocity is 10.0h^-1And reacting under the condition that the reaction pressure is 3.0MPa, wherein the olefin content in the dehydrogenation product is 42.5%.

The present invention is capable of other embodiments, and various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A mixed C-C conversion method is characterized in that the conversion process at least comprises the following steps: the first step, mixing a carbon four raw material, a material flow containing an oxidant and water or steam, feeding the mixture into an oxidative dehydrogenation unit, reacting in a reactor filled with an oxidative dehydrogenation catalyst, feeding the mixture into a separation unit I, and separating the reacted material flow into butadiene, other carbon four fractions and other components; secondly, sending other carbon four fractions separated in the first step and alcohol material flows into an etherification unit, carrying out etherification reaction in a reactor filled with an etherification catalyst, sending reaction products into a separation unit II, and separating the material flows after the reaction into more than five carbon components, carbon four hydrocarbons and other components; thirdly, the carbon tetrahydrocarbon and hydrogen separated in the second step are sent into a catalytic dehydrogenation unit, alkane catalytic dehydrogenation reaction is carried out in a reactor filled with a catalytic dehydrogenation catalyst, non-condensable gas is separated from the material flow after catalytic dehydrogenation through a separation unit III, and the material flow and the mixed carbon tetrahydrocarbon raw material are sent into an oxidative dehydrogenation unit;

wherein, the mixed C-C raw material refers to C-C hydrocarbon generated in the oil refining and chemical engineering process; or the mass content of the carbon four hydrocarbon in the mixed carbon four is not less than 95%, or the mass content of the olefin in the mixed carbon four is not less than 40%, or the mass sum of the n-butene and the n-butane in the mixed carbon four is not less than 35%;

the reaction conditions of the oxidative dehydrogenation unit are as follows: the temperature is 280-410 ℃, the pressure is 0-100 KPa, and the volume space velocity is 10-500 h^-1；

And the molar ratio of the oxygen to the olefin of all hydrocarbon materials entering the oxidative dehydrogenation unit is 0.1-1.0: 1 in terms of oxygen in the stream containing the oxidant.

2. The mixed C-C conversion process of claim 1, wherein the mixed C-C feedstock is selected from the group consisting of post-ether C-C, catalytically cracked C-C, cracked C-C and/or separated fractions of light gasoline; or the mass content of the carbon four hydrocarbon in the mixed carbon four is not less than 99 percent, or the mass content of the olefin in the mixed carbon four is not less than 50 percent, or the mass sum of the n-butene and the n-butane in the mixed carbon four is not less than 40 percent.

3. The mixed C-IV conversion process of claim 1, wherein the oxidative dehydrogenation unit has an n-butene conversion of not less than 70%.

4. The mixed C-IV conversion process of claim 3, wherein the oxidative dehydrogenation unit has an n-butene conversion of not less than 75%.

5. The mixed carbon-four conversion process of claim 1, wherein the reaction conditions of the oxidative dehydrogenation unit are: the temperature is 310-395 ℃, the pressure is 0-40 KPa, and the volume space velocity is 60-400 h^-1。

6. The mixed C/D conversion process of claim 1, wherein the oxidant of the oxidative dehydrogenation unit is a stream containing molecular oxygen or a stream containing strongly oxidizing oxygen atoms.

7. The mixed carbon-four conversion process of claim 6, wherein the oxidant of the oxidative dehydrogenation unit is air, oxygen-rich gas, or oxygen.

8. The mixed carbon-four conversion process of claim 1, wherein the molar ratio of oxygen to olefin in the stream containing the oxidant to all hydrocarbon feed entering the oxidative dehydrogenation unit is from 0.3 to 0.85:1, calculated as oxygen.

9. The mixed carbon-four conversion process of claim 1, wherein the mass ratio of water vapor in the oxidative dehydrogenation unit to butylene in all hydrocarbon materials entering the oxidative dehydrogenation unit is 0.5-30.

10. The mixed carbon-four conversion process of claim 9, wherein the mass ratio of water vapor in the oxidative dehydrogenation unit to butenes in all hydrocarbon feeds entering the oxidative dehydrogenation unit is 5 to 20.

11. The hybrid carbon-four conversion process of claim 1, wherein the butadiene content of the carbon-four fraction after butadiene separation in separation unit I is no greater than 0.3%.

12. The hybrid carbon-four conversion process of claim 11, wherein the butadiene content of the carbon-four fraction after butadiene separation in separation unit I is no greater than 0.1%.

13. The mixed carbon-four conversion process of claim 1, wherein the isobutylene conversion in the etherification reaction unit is no less than 92%.

14. The mixed carbon-four conversion process of claim 1, wherein the alcohol stream in the etherification reaction unit is a lower alcohol.

15. The mixed carbon-four conversion process of claim 14, wherein the alcohol streams in the etherification reaction units are methanol and ethanol.

16. The mixed C-IV conversion process of claim 1, wherein the molar ratio of the alcohols to isobutylene in all hydrocarbon materials entering the etherification unit is 0.8-1.5: 1.

17. The mixed carbon-four conversion process of claim 16, wherein the molar ratio of the alcohols to isobutylene in all hydrocarbon materials entering the etherification unit is 1.1-1.3: 1.

18. The mixed carbon-four conversion process of claim 1, wherein the etherification reactions are carried out under the reaction conditions: the temperature is 30-100 ℃, the pressure is 0.1-2.0 MPa, and the volume space velocity is 0.1-5 h^-1。

19. The mixed carbon-four conversion process of claim 18, wherein the etherification reactions occur under the reaction conditions: the temperature is 45-80 ℃, the pressure is 0.5-1.5 Mpa, and the volume space velocity is 1-2 h^-1。

20. The mixed C-IV conversion process of claim 1, wherein the C-IV hydrocarbons separated by separation unit II contain not less than 97% by weight of C-IV hydrocarbons.

21. The mixed C-IV conversion process of claim 20, wherein the C-IV hydrocarbons separated by separation unit II contain not less than 99% by weight of C-IV hydrocarbons.

22. The mixed carbon-four conversion process of claim 1, wherein the catalytic dehydrogenation product in the catalytic dehydrogenation unit has an olefin content of no less than 35%.

23. The mixed carbon-four conversion process of claim 22, wherein the olefin content of the catalytic dehydrogenation product in the catalytic dehydrogenation unit is greater than 45%.

24. The mixed carbon-four conversion process of claim 1, wherein the reaction conditions of the catalytic dehydrogenation unit are: the temperature is 480-700 ℃, the pressure is 0.01-3 MPa, and the liquid volume space velocity is 0.1-10 h^-1。

25. The hybrid carbon-four conversion process of claim 24, wherein the reaction conditions of the catalytic dehydrogenation unit are: the temperature is 560-650 ℃, the pressure is 0.4-1.2 MPa, and the liquid volume space velocity is 2-7 h^-1。

26. The mixed carbon-four conversion process of claim 1, wherein the molar ratio of hydrogen to all hydrocarbon feed entering the catalytic dehydrogenation unit is 0.01-1: 1.

27. The mixed carbon-four conversion process of claim 26, wherein the molar ratio of hydrogen to all hydrocarbon feed entering the catalytic dehydrogenation unit is 0.1 to 0.5: 1.

28. The mixed carbon-four conversion process of claim 1, wherein the catalytic dehydrogenation reactor in the catalytic dehydrogenation unit is used in parallel with two or more fixed bed reactors.