Method for preparing acetone by oxidation of isoparaffin

Abstract

A method for preparing acetone from isoparaffin comprises: using isoparaffin as a raw material, under the action of a catalyst, oxidizing the isoparaffin to acetone at a temperature of 50-500° C.; the catalyst comprises an active component and a carrier, wherein the active component comprises a metal element, or the active component comprises a metal element and a zeolite molecular sieve, and the content of the metal element is 0.1-40wt%. The method avoids the danger caused by the complicated reaction process and the generation of organic peroxides, improves the safety of the reaction, and reduces the production cost; the byproduct of the reaction product is also a raw material for MTBE, and the economic benefit is good.

Description

Technical Field

[0001] The present application relates to a method for preparing acetone, and in particular, to a method for directly preparing acetone by isomerization oxidation. Background Art

[0002] The simplest saturated ketone, acetone, is an important organic chemical raw material, mainly used in the production of organic glass, medicine, pesticides, epoxy resin, polycarbonate. In addition, it can also be used as a solvent in industrial production.

[0003] The main methods for producing acetone include fermentation, organic matter hydration, propylene oxidation, isobutyraldehyde oxidation, etc.

[0004] The earliest production method of acetone is fermentation. This method uses grains or other sugars as raw materials, and obtains sterile fermentation liquid after high-temperature boiling and sterilization. Then, a specific strain of bacteria is added for fermentation. After fermentation, the liquid can be distilled to obtain acetone. The fermentation method has backward technology, high production cost and low efficiency. At present, this method has been basically eliminated.

[0005] Chinese patent application publication number CN104402692A discloses biomimetic catalytic isobutane to prepare acetone, using isobutane as a raw material, oxygen as an oxygen source, adding a solvent, an auxiliary agent and a free radical initiator, the catalyst is μ-oxygen-binuclear metalloporphyrin, the auxiliary agent is one of multi-walled carbon nanotubes, carboxylated carbon nanotubes, activated carbon, etc., and the solvent is selected from one of methanol, acetonitrile, ethyl acetate, etc. Acetone is prepared by catalytic reaction under the action of the catalyst.

[0006] The propylene oxidation method uses oxygen as an oxidant to oxidize propylene to acetone, and copper chloride-palladium chloride as an active component catalyst to catalyze the oxidation of propylene to acetone, and the catalyst can be recycled through the following reaction. First, propylene is oxidized to PdCl 2 Reduced to Pd, acetone and HCl are generated at the same time, and Pd is absorbed by another component CuCl on the catalyst. 2 Oxidized again to PdCl 2 , while CuCl 2 is reduced to CuCl, and finally CuCl is reacted with HCl and O 2 Under the action of 2 , thus completing the cycle.

[0007]

[0008] Pd+2CuCl 2 →PdCl 2 +2CuCl

[0009] 2CuCl+1 / 2O 2 +2HCl→2CuCl2 +H 2 O

[0010] Although this method has a high yield of acetone, it is difficult to apply in industry due to the price of the reaction raw material isobutyraldehyde.

[0011] Chinese patent application CN201410431315.1 discloses a method for synthesizing acetone using synthesis gas as raw material. The method uses CO and H in the synthesis gas as raw materials. 2 As raw materials, methanol is first synthesized, and then methanol and CO are carbonylated to produce acetone. This method has low efficiency in producing acetone and is not conducive to the continuous production of acetone.

[0012] Chinese patent application publication Nos. CN106946639A, CN106883107A and CN106883088A disclose a method of generating ethylene, acetaldehyde and acetone through a photocatalytic reaction of ethanol in the presence of Au and Ag-based catalysts. This method has a low acetone yield, high cost and low efficiency.

[0013] US Patent No. 6933414B1 discloses a method for generating acetone from formaldehyde and methyl chloride, the products of which are acetone and hydrochloric acid. This method has high production cost and is prone to environmental pollution.

[0014] At present, the main production method of acetone is the cumene oxidation method, and the main production steps of this method are the synthesis of cumene, the peroxidation of cumene, the concentration, decomposition and neutralization of cumene peroxide, and product refining.

[0015] It is reported in the literature that, with cumene peroxide as the raw material, the temperature of the reactor gradually increases with the flow of the raw material. First, a mixture of cumene peroxide and dicumyl peroxide is generated under the catalytic action of concentrated sulfuric acid, and then the reaction temperature is increased to decompose dicumyl peroxide into a mixed solution of acetone and phenol, and the products phenol and acetone are obtained through distillation and other methods. Alternatively, with a mixed solution of cumene peroxide and cumene as the raw material, the reaction temperature is first 40 to 75°C, and under the catalytic action of organic acids such as 2-hydroxy-5-methyl-benzenesulfonic acid, 4-hydroxybenzene-1,3-disulfonic acid, 2-hydroxy-5-methoxybenzenesulfonic acid, etc., a mixed solution of dicumyl peroxide and cumene is generated, and then the reaction temperature is increased to 110 to 140°C to generate a mixed solution of acetone and phenol, and the acetone product can be obtained after distillation and purification. This method requires a large amount of acid, and the mixed solution after the reaction needs to be added to neutralize the excess acid before refining. Cumene can also be used as a raw material, and part of the cumene is oxidized to cumene peroxide in the presence of oxygen to obtain a mixture of cumene hydroperoxide and cumene. The above-mentioned mixed solution contacts a non-acidic catalyst, and a part of the cumene peroxide and unreacted cumene in the mixed solution generate dimethylbenzyl alcohol. The solution containing dimethylbenzyl alcohol is contacted with an acidic catalyst to generate α-methylstyrene, acetone and phenol. This method effectively avoids the use of concentrated sulfuric acid and alkaline substances, reduces equipment corrosion and reduces production costs. Summary of the invention

[0016] One purpose of the present application is to directly prepare acetone from isomerized alkanes, thereby avoiding the complicated reaction process and the danger caused by the generation of organic peroxides, improving the safety of the reaction and reducing the production cost.

[0017] Another purpose of the present application is to directly prepare acetone from isomerized alkanes, and the by-product of the reaction product is also a raw material for MTBE, which has good economic benefits.

[0018] A method for preparing acetone from isoparaffin comprises: using isoparaffin as a raw material, oxidizing the isoparaffin to acetone under the action of a catalyst at a temperature of 50-500°C; the catalyst comprises an active component and a carrier, wherein:

[0019] The active component is a metal element, and the metal element includes one or a mixture of two or more of Ce, Nb, W, V, Mo, Ti, Zr, Fe, Ni, Cr, Zn and Ag; or,

[0020] The active component is a mixture of metal elements and zeolite molecular sieves, and the metal elements include: one or a mixture of two or more of Mn, Co, Zr, Nb, W, V, Cu, Fe, Ni, Ce, Ti, Cr, Mo, Zn and Ag elements.

[0021] The content of the metal element is 0.1-40wt%.

[0022] The isomerized alkane of the present application is directly catalytically oxidized to acetone, has no co-products, and has high production flexibility. No organic peroxides are generated during the reaction process, thereby improving production safety and reducing the generation of by-products. DETAILED DESCRIPTION

[0023] The method for preparing acetone from isoparaffins of the present application is further described in detail below. The scope of protection of the present application is not limited, and its scope of protection is defined by the claims. Certain disclosed specific details provide a comprehensive understanding of each disclosed embodiment. However, those skilled in the relevant art know that the embodiment can be implemented without using one or more of these specific details and using other materials, etc.

[0024] Unless the context requires otherwise, in the specification and claims, the terms "include" and "comprising" should be construed as having an open-ended, inclusive meaning, that is, "including, but not limited to".

[0025] The "embodiment", "one embodiment", "another embodiment" or "certain embodiments" mentioned in the specification means that the specific features, structures or characteristics described in connection with the embodiment are included in at least one embodiment. Therefore, "embodiment", "one embodiment", "another embodiment" or "certain embodiments" do not necessarily all refer to the same embodiment. Moreover, specific features, structures or characteristics may be combined in any manner in one or more embodiments. Each feature disclosed in the specification may be replaced by any alternative feature that can provide the same, equal or similar purpose. Therefore, unless otherwise specified, the disclosed features are only general examples of equal or similar features.

[0026] The isoalkane in the present application refers to a branched alkane relative to a normal alkane, for example, an alkane having a methyl substituent at the 2- or 3-position, 2-methylalkane, 3-methylalkane, and the like.

[0027] The content of metal elements in the catalyst is calculated as the highest valent oxide and is the ratio of the mass of the catalyst.

[0028] At present, acetone is prepared industrially by the cumene oxidation process. Benzene and propylene are used as raw materials. Cumene is generated through an alkylation reaction. Cumene is then oxidized by air to convert it into cumene peroxide. Finally, cumene peroxide is converted into phenol and acetone under the action of a catalyst.

[0029] In addition to the need to generate dangerous isopropylbenzene peroxide, this method also has the following problems: the raw materials benzene and propylene are both important intermediate raw materials for chemical production, with huge demand and high prices; the production process is complicated and requires alkylation, oxidation, catalytic decomposition, separation and purification, etc.; the decomposition of isopropylbenzene peroxide generates one molecule of acetone and one molecule of phenol at the same time, that is, the production of 1 ton of acetone will produce 1.6 tons of phenol, and the production flexibility of acetone is subject to the market demand for phenol. This application uses oxygen to directly oxidize isoparaffins to produce acetone.

[0030] A method for preparing acetone from isoparaffin, comprising: using isoparaffin as a raw material, under the action of a catalyst, oxidizing the isoparaffin to acetone at a temperature of 50-500° C.; the catalyst comprises: an active component and a carrier, wherein the active component comprises a metal element, the active component is a metal element, and the metal element comprises one or a mixture of two or more of Ce, Nb, W, V, Mo, Ti, Zr, Fe, Ni, Cr, Zn and Ag elements; or

[0031] The active component is a mixture of metal elements and zeolite molecular sieves, wherein the metal elements include one or a mixture of two or more of Mn, Co, Zr, Nb, W, V, Cu, Fe, Ni, Ce, Ti, Cr, Mo, Zn and Ag elements, wherein the content of the metal elements is 0.1-40wt%.

[0032] In the above method, isoparaffin and oxygen generate acetone and alcohol substances under the action of catalyst.

[0033] In certain embodiments, the isoalkane includes isomerized alkanes below C10, preferably isomerized alkanes below C7, and more preferably isobutane.

[0034] In certain embodiments, the oxidant comprises oxygen.

[0035] In certain embodiments, the content of the metal element in the catalyst is 0.3-20 wt %.

[0036] The above-mentioned metal elements may exist in the form of metal or metal oxide, preferably metal oxide.

[0037] In certain embodiments, the active metal element in the catalyst is preferably WO 3 、TiO 2 、MnO x 、MoO x 、CoO x ,FeO x , CuO x One or more of the .

[0038] In certain embodiments, the support comprises Al 2 O 3 、SiO 2 , kaolin, diatomaceous earth, MgO, CaO and La 2 O 3 One or more of the following. Preferably Al 2 O 3 、SiO 2 and kaolin or a mixture of both.

[0039] In certain embodiments, the active element is selected from one or a combination of multiple metal elements including Co, Mo, Mn, Ti, and Fe.

[0040] In the catalyst, the content of the active component metal element is 5.0-15wt%.

[0041] In certain embodiments, isoparaffin reacts with oxygen under the action of the above catalyst to produce acetone. The preferred reaction temperature is controlled within the range of 120-350°C.

[0042] In certain embodiments, isoparaffin reacts with oxygen under the action of the above catalyst, and the reaction temperature is controlled within the range of 170-200°C.

[0043] Under this condition, the selectivity of acetone in the reaction of isoalkanes to prepare acetone is higher.

[0044] In certain embodiments, the contact reaction time of isoparaffin and oxygen with the catalyst is 3-240 min. The contact time is preferably controlled at 15-180 min. Preferably, the contact reaction time of isoparaffin and oxygen with the catalyst is 40-150 min.

[0045] In the present application, a mixture of isoparaffins and oxygen is contacted with the above catalyst and converted into acetone and corresponding alcohols at a temperature below 300°C.

[0046] In certain embodiments, the total pressure of isoparaffin and oxygen in the reactor is 0.1-15 MPa, preferably controlled at 0.5-10 MPa.

[0047] In certain embodiments, in the mixture of isoparaffin and oxygen, the volume ratio of oxygen is 1-50%, preferably controlled at 5-30%.

[0048] In certain embodiments, the reaction raw material is isobutane, and in the mixed gas of isobutane and oxygen, the proportion of oxygen is 1-50%, preferably controlled at 5-30%.

[0049] The active component metal element is loaded on the carrier, and in the reaction of directly preparing acetone from isoparaffin, the selectivity of acetone is high and can reach more than 40%.

[0050] The content of zeolite molecular sieve in the catalyst is 5%-80wt%, preferably 20-50wt%. In some embodiments, the zeolite molecular sieve includes one or a mixture of two or more of Y-type molecular sieve, USY-type molecular sieve, ZSM-5-type molecular sieve, type molecular sieve, mordenite and offretite.

[0051] In the catalyst, the content of the zeolite molecular sieve is 5wt%-80wt%, preferably 20wt%-50wt%.

[0052] In certain embodiments, the zeolite molecular sieve is selected from one or a mixture of two or more of USY, ZSM-5 and β-type molecular sieves.

[0053] The active component metal and the zeolite molecular sieve are both active as catalysts, and have better catalytic performance in the reaction system of preparing acetone from isoparaffins, and the selectivity of acetone in the obtained product is higher.

[0054] In some embodiments, the active components of the catalyst are metal elements and zeolite molecular sieves, wherein the metal elements include one or a mixture of two or more of Ce, Ti, Zr, Nb, W, V, Cr, Mo, Fe, Ni, Zn and Ag elements, and the content of zeolite molecular sieve is preferably 20-40wt%.

[0055] In certain embodiments, the active components of the catalyst are metal elements and zeolite molecular sieves, wherein the metal elements include one or a mixture of two or more of Mn, Co, and Cu elements, and the content of the zeolite molecular sieve is preferably 20-50 wt%.

[0056] The Si / Al ratio in the zeolite molecular sieve is 1-500, preferably 3-200, more preferably 3-50.

[0057] Active elements such as Co, Mo, and Mn metals work together with molecular sieves. The metal elements reduce the isoalkane oxides to alcohols, and then the molecular sieves can further oxidize acetone and alcohols. In particular, when the Si / Al in the molecular sieve is 3-200, a better catalytic effect can be obtained.

[0058] Here, Si / Al refers to the molar ratio or atomic ratio of Si element to Al element in the zeolite molecular sieve.

[0059] In the catalyst, in addition to the above-mentioned active component metal element, or the content of the metal element and the zeolite molecular sieve, the rest is the carrier.

[0060] In the method for preparing acetone of the present application, the catalyst contains zeolite molecular sieve, which has better catalytic performance in catalytic oxidation isomerization of alkanes. In addition to acetone and alcohol substances, the content of other by-products is less.

[0061] Under the action of the catalyst, the main by-products of the reaction system for isomerizing alkanes to prepare acetone are tert-butyl alcohol, methanol and isobutylene, which are all raw materials for producing MTBE. There are very few by-products such as XO, XO2, methane and water.

[0062] The catalyst preparation method can adopt the common preparation method in the prior art. The catalyst can be manufactured by a method of first beating the pulp and then spraying the granules; it can also be manufactured by a method of kneading and then extruding strips; it can also be manufactured by a rolling ball method.

[0063] On the other hand, in the preparation method of the catalyst for preparing acetone from isoparaffin, a substance containing metal elements and / or molecular sieves is mixed with a sol containing a carrier component, and the mixture is dried and calcined to obtain a catalyst.

[0064] The substance containing metal elements is an oxide containing metal elements.

[0065] In certain embodiments, the calcination temperature is controlled at 550-750°C.

[0066] On the other hand, the preparation method of the above-mentioned catalyst for preparing acetone from isoparaffin includes first loading the metal element on the zeolite molecular sieve by impregnation method, mixing the loaded zeolite molecular sieve with a sol containing a carrier component, and obtaining the catalyst after drying and calcining.

[0067] The substance containing metal elements is a water-soluble salt containing metal elements.

[0068] The mass concentration of the water-soluble salt containing the metal element is 1-60%, preferably 10-40%.

[0069] Compared with the current industrial production method of acetone, the advantages of this application are:

[0070] 1) Isobutane and oxygen directly generate acetone in a reactor in one step, avoiding the complicated reaction process and the danger caused by the generation of organic peroxides, improving the safety of the reaction and reducing the production cost.

[0071] 2) When isobutane is selected as the isoalkane, the selectivity of acetone is above 40%, the conversion rate of oxygen is above 90%, there is no co-product, and the production flexibility is high.

[0072] 3) The raw materials of this method, isobutane and oxygen, are widely available and inexpensive, the yield of low-value by-products is low, and the economic benefits are good. Taking isobutane as an example, the target product of the reaction is acetone, and the main by-products are tert-butyl alcohol, methanol and isobutylene, which are all raw materials for the production of MTBE. 2 There are very few by-products such as methane and water.

[0073] The method for preparing acetone from isoparaffin of the present application is further described below with reference to specific examples.

[0074] In the following examples, all materials used in the following examples are commercially available. 2 Taking the catalyst as an example, the number 10 in front of the Mn element represents the weight ratio of Mn oxide in the catalyst, and the number 30 in front of ZSM represents the weight ratio of the molecular sieve ZSM-5 in the catalyst.

[0075] Example 1

[0076] In this example, isobutane is used as raw material, 10Mn-30ZSM / SiO 2 The catalyst is in a fixed bed reactor. Reaction conditions: temperature 170°C, 3Mpa, residence time 60min; oxygen content in the feed gas is 20%, and the reaction results are shown in Table 1. The conversion rate and selectivity involved in the reaction results are calculated based on mass fraction.

[0077] 10Mn-30ZSM / SiO 2 Preparation method of catalyst: Take a certain amount of silica sol (SiO 2 A certain amount of ZSM-5 molecular sieve (so that the mass fraction of ZSM in the final catalyst is 30%) and a certain amount of MnO 2 powder (so that the final catalyst contains MnO 2 The mass fraction of ZSM-5 molecular sieve is 10%, wherein the Si / Al of ZSM-5 molecular sieve is 38; after stirring for 2 hours, drying at 120°C and calcining at 700°C for 2 hours, 10Mn-30ZSM / SiO 2 catalyst.

[0078] Example 2

[0079] In this example, isobutane is used as the raw material, 10Co-30USY / Al 2 O 3The catalyst is in a fixed bed reactor. Reaction conditions: temperature 170°C, 3Mpa, residence time 60min; oxygen content in the feed gas is 20%, and the reaction results are shown in Table 1. The conversion rate and selectivity involved in the reaction results are calculated based on mass fraction.

[0080] 10Co-30USY / Al 2 O 3 Preparation method of catalyst: Take a certain amount of aluminum sol (Al 2 O 3 A certain amount of USY molecular sieve (making the mass fraction of USY in the final catalyst to be 30%) and a certain amount of CoO powder (making the mass fraction of CoO in the final catalyst to be 10%) were added, wherein the Si / Al of USY molecular sieve was 6. After stirring for 2 hours, the mixture was dried at 120°C and calcined at 700°C for 2 hours to obtain 10Co-30USY / Al 2 O 3 catalyst.

[0081] The catalysts used in the following Examples 3-12 are all 10Co-30USY / Al prepared in Example 2. 2 O 3 The catalyst is different, but the reaction conditions are adjusted.

[0082] Example 3

[0083] In a fixed bed reactor, using isobutane as feedstock, 10Co-30USY / Al 2 O 3 The reaction temperature was 150°C, the reaction pressure was 3Mpa, the residence time was 60min, the oxygen content in the feed gas was 20%, and the feed was sampled and analyzed after stabilization. The reaction results are shown in Table 1.

[0084] Example 4

[0085] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 180°C, the reaction pressure was 3 MPa, the residence time was 60 min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0086] Example 5

[0087] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3The catalyst was 200°C, the reaction pressure was 3 MPa, the residence time was 60 min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0088] Example 6

[0089] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 2Mpa, the residence time was 60min, the proportion of oxygen in the raw material was 20%, and the sample was analyzed after the feed was stable. The reaction results are shown in Table 1.

[0090] Example 7

[0091] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 1 MPa, the residence time was 60 min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0092] Example 8

[0093] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 3 MPa, the residence time was 40 min, the proportion of oxygen in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0094] Example 9

[0095] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 3 MPa, the residence time was 100 min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0096] Example 10

[0097] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 3 MPa, the residence time was 60 min, the oxygen content in the raw material was 5%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0098] Embodiment 11

[0099] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 3 MPa, the residence time was 60 min, the oxygen content in the raw material was 10%, and the sample was analyzed after the feed was stable. The reaction results are shown in Table 1.

[0100] Example 12

[0101] In a fixed bed reactor, isobutane was used as the raw material and 10Co-30USY / Al 2 O 3 The catalyst was 170°C, the reaction pressure was 3 MPa, the residence time was 60 min, the oxygen content in the raw material was 25%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 1.

[0102] Example 13

[0103] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Cu-30ZSM / SiO 2 Other conditions are as shown in Example 1. The reaction results are shown in Table 1.

[0104] 10Cu-30ZSM / SiO 2 The preparation method comprises: taking a certain amount of silica sol (SiO 2 A certain amount of ZSM-5 molecular sieve (making the mass fraction of ZSM in the final catalyst to be 30%) and a certain amount of CuO powder (making the mass fraction of CuO in the final catalyst to be 10%) were added to a stirring kettle, and the mixture was stirred for 2 hours, dried at 120°C, and calcined at 700°C for 2 hours to obtain 10Cu-30ZSM / SiO 2 catalyst.

[0105] Embodiment 14

[0106] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Ti-30Hβ / Al 2 O 3 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0107] 10Ti-30Hβ / Al 2 O 3 The preparation method comprises: taking a certain amount of aluminum sol (with Al 2 O 3The catalyst was stirred in a stirred tank, and then a certain amount of Hβ molecular sieve (so that the mass fraction of Hβ in the final catalyst was 30%) and a certain amount of TiO 2 powder (so that the final catalyst contains TiO 2 The mass fraction of Hβ molecular sieve is 10%), Si / Al=21, and after stirring for 2h, drying at 120℃ and calcining at 700℃ for 2h, 10Ti-30Hβ / Al 2 O 3 catalyst.

[0108] Embodiment 15

[0109] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Fe / Al 2 O 3 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0110] 10Fe / Al 2 O 3 Preparation method of catalyst: Take a certain amount of aluminum sol (Al 2 O 3 , mass fraction is 30%) in a stirred tank, and then a certain amount of Fe 2 O 3 (so that the Fe 2 O 3 The mass fraction of 10% was obtained by stirring for 2 hours, drying at 120°C, and calcining at 700°C for 2 hours. 2 O 3 catalyst.

[0111] Example 16

[0112] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Mo / SiO 2 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0113] 10Mo / SiO 2 Preparation method of catalyst: Take a certain amount of silica sol (SiO 2 The mass fraction is 30%) and placed in a stirring kettle for stirring, and then a certain amount of MoO 3 (so that the MoO 3 The mass fraction of 10% was obtained by stirring for 2 hours, drying at 120°C, and calcining at 700°C for 2 hours. 2 catalyst.

[0114] Embodiment 17

[0115] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Ti / Al 2 O 3 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0116] 10Ti / Al 2 O 3 Preparation method of catalyst: Take a certain amount of silica sol (SiO 2 The mass fraction is 30%) and placed in a stirring tank for stirring, and then a certain amount of TiO 2 (so that the final catalyst contains TiO 2 The mass fraction of 10% was obtained by continuing to stir for 2 hours, drying at 120°C, and calcining at 700°C for 2 hours. 2 O 3 catalyst.

[0117] Embodiment 18

[0118] The method for preparing acetone in this embodiment is different from that in embodiment 1 in that the catalyst is 10Cu / Al 2 O 3 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0119] 10Cu / Al 2 O 3 Preparation method of catalyst: Take a certain amount of silica sol (SiO 2 The catalyst was placed in a stirred tank and stirred, and then a certain amount of CuO was added (so that the mass fraction of CuO in the final catalyst was 10%). After stirring for 2 hours, it was dried at 120°C and calcined at 700°C for 2 hours to obtain 10Cu / Al 2 O 3 catalyst.

[0120] Examples 19-22

[0121] The method for preparing acetone in Examples 19-22 is different from that in Example 1 in that the catalyst is 10Cu-30ZSM / SiO 2 Other conditions are as shown in Example 1. The reaction results are shown in Table 2.

[0122] 10Cu-30ZSM / SiO 2 The preparation method of is referred to Example 13, except that the silicon-aluminum ratio of the ZSM-5 molecular sieve is different. The silicon-aluminum ratio of Example 19 is 26; the silicon-aluminum ratio of Example 20 is 100; the silicon-aluminum ratio of Example 21 is 200; and the silicon-aluminum ratio of Example 22 is 500.

[0123] Comparative Example 1

[0124] The comparative example is a method for preparing acetone, the raw material is isobutane. In a fixed bed reactor, quartz sand is filled, the reaction temperature is 170°C, the reaction pressure is 3Mpa, the residence time is 60min, the proportion of oxygen in the raw material is 20%, and sampling and analysis are performed after the feed is stable. The reaction results are shown in Table 2.

[0125] Comparative Example 2

[0126] In this comparative example, the method for preparing acetone is based on isobutane as the raw material. 2 O 3 The catalyst was 90°C, the reaction pressure was 3Mpa, the residence time was 60min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 2.

[0127] Comparative Example 3

[0128] In this comparative example, the method for preparing acetone is based on isobutane as the raw material. 2 O 3 The catalyst was 170°C, the reaction pressure was 0.1 MPa, the residence time was 60 min, the oxygen content in the raw material was 20%, and the sample was analyzed after the feed was stable. The reaction results are shown in Table 2.

[0129] Comparative Example 4

[0130] In this comparative example, the method for preparing acetone is based on isobutane as the raw material. 2 O 3 The catalyst was 180°C, the reaction pressure was 3 MPa, the residence time was 5 min, the oxygen content in the raw material was 20%, and the sample was taken for analysis after the feed was stable. The reaction results are shown in Table 2.

[0131] Table 1

[0132]

[0133] Table 2

[0134]

Claims

1. A method for preparing acetone from isoparaffins, include: Isoparaffin and oxygen are oxidized to acetone under the action of a catalyst at a temperature of 120-350° C., wherein the total partial pressure of isoparaffin and oxygen in the reactor is 0.5 MPa-10 MPa, and the contact reaction time of isoparaffin and oxygen with the catalyst is controlled at 15 min-180 min; the catalyst comprises: an active component and a carrier, wherein: The active component is a metal oxide, wherein the metal in the metal oxide is selected from: one or a mixture of two or more of Ce, Nb, W, V, Mo, Ti, Zr, Fe, Ni, Cr, Zn and Ag; or, The active component is a mixture of metal oxide and zeolite molecular sieve, the Si / Al ratio of the zeolite molecular sieve is 1-500, and the metal in the metal oxide is selected from: one or a mixture of two or more of Mn, Co, Zr, Nb, W, V, Cu, Fe, Ni, Ce, Ti, Cr, Mo, Zn and Ag; The carrier is selected from Al 2 O 3 、SiO 2 , kaolin, diatomaceous earth, MgO, CaO and La 2 O 3 One or more of the following; The isoalkane is selected from isobutane; The content of the metal oxide is 0.1wt%-40wt%.

2. The method according to claim 1, It is characterized in that The reaction is carried out under the action of a catalyst, and the reaction temperature is controlled within the range of 170-200°C.

3. The method according to claim 1, It is characterized in that The contact reaction time of isoparaffin and oxygen with the catalyst is 60 min-100 min.

4. The method according to claim 1, It is characterized in that The total partial pressure of isoparaffin and oxygen in the reactor is 1MPa-3Mpa.

5. The method according to claim 1, It is characterized in that In a mixture of isobutane and oxygen, the proportion of oxygen is 1-50%.

6. The method according to claim 1, It is characterized in that In a mixture of isobutane and oxygen, oxygen accounts for 5-30%.

7. The method according to any one of claims 1 to 6, It is characterized in that The content of metal oxide in the catalyst is 0.3 - 20 wt%.

8. The method according to any one of claims 1 to 6, It is characterized in that The active component in the catalyst is selected from WO 3 、TiO 2 One or more of the .

9. The method according to any one of claims 1 to 6, It is characterized in that The carrier is selected from Al 2 O 3 、SiO 2 and kaolin or a mixture of both.

10. The method according to any one of claims 1 to 6, It is characterized in that The metal of the metal oxide is selected from one or a combination of multiple ones of Co, Mo, Mn, Ti and Fe.

11. The method according to claim 10, It is characterized in that In the catalyst, the content of the active component metal oxide is 5.0 - 15 wt%.

12. The method according to any one of claims 1 to 6, It is characterized in that The Si / Al ratio of the zeolite molecular sieve in the catalyst is 3-200.

13. The method according to claim 1, It is characterized in that The content of zeolite molecular sieve in the catalyst is 5-80wt%.

14. The method according to claim 1, It is characterized in that The content of zeolite molecular sieve in the catalyst is 20-50wt%.

15. The method according to claim 1, It is characterized in that The zeolite molecular sieve is one or a mixture of two or more of Y-type molecular sieve, USY-type molecular sieve, ZSM-5-type molecular sieve, β-type molecular sieve, mordenite and offretite.

16. The method according to claim 15, It is characterized in that In the catalyst, the content of zeolite molecular sieve is 5wt%-80wt%.

17. The method according to claim 15, It is characterized in that In the catalyst, the content of zeolite molecular sieve is 20wt%-50wt%.

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