Catalyst for preparing acrylic acid and butyl ester using lactic acid method and preparation method thereof

Abstract

The invention discloses a catalyst used for preparing acrylic acid and butyl ester by the dehydration of butyl lactate and a preparation method thereof. The catalyst is a composite catalyst, comprising a main catalyst A and auxiliary catalysts B, C, D and E, wherein, A is calcium sulphate, B is sulphuric acid, C is phosphate, D is alkaline matter and E is promoter. The preparation method comprises the steps as follows: five compositions A, B, C, D and E are sufficiently mixed, baked for 2-10 hours at the temperature of 200-800DEG C and formed for standby. The catalyst has high catalytic activation; under the catalysis of the catalyst, the molar yield reaches 75.1 percent and the molar selectivity of the acrylic acid and butyl ester reaches 71.5 percent. The preparation method has the advantages that the crystal structure of the main catalyst can be improved so as to be beneficial for carrying out the reaction; and the introduction of different auxiliary catalysts and quantities is helpful to improve the conversion ratio of the raw material and the product selectivity and is beneficial for improving the strength of the catalyst.

Description

Technical field

[0001] The invention relates to the composition and preparation method of a catalyst for preparing acrylic acid by dehydration of butyl lactate and its butyl ester. Background technique

[0002] Acrylic acid and its butyl ester are basic organic chemical raw materials, and they are used in huge amounts in coatings, paints, adhesives, synthetic rubber, plastics, and water-absorbent resins. The preparation processes of acrylic acid and its butyl ester mainly include: cyanoethanol method, improved Reppe method, acrylonitrile hydrolysis method, and propylene oxidation method. The dominant one is the propylene oxidation method, which is currently used in 90% of operating devices.

[0003] The propylene oxidation method uses petroleum cracked product propylene as the raw material. The process is divided into two steps: the first step is to oxidize propylene to acrolein; in the second step, acrolein is further oxidized to acrylic acid. The raw material of the process comes from petroleum, which is not renewable. Resources will inevitably be exhausted in the foreseeable future, and world oil prices continue to rise. As of May 2008, oil prices have risen to 130 US dollars per barrel. With the continuous depletion of petroleum resources and the rise of oil prices, the source of raw materials for the production of acrylic acid and its butyl ester by propylene oxidation method has gradually decreased, and the production cost has continued to increase. However, the market demand for acrylic acid and its butyl ester has continued to increase. Solving this contradiction and exploring a new preparation process for acrylic acid and its butyl ester has become a top priority no matter from the perspective of future industry development or from the perspective of current actual industrial production.

[0004] Biological lactic acid is a typical renewable resource, which can be obtained through the fermentation of crops, and its process technology has been very mature. Lactic acid and acrylic acid have similarities in molecular structure, and the development of a process for preparing acrylic acid and its derivatives using biological lactic acid as the starting material has broad prospects.

[0005] In 1958, the patent US2859240 first reported the research work on the preparation of acrylic acid from lactic acid. The gas-solid phase reaction was adopted to realize the conversion of lactic acid to acrylic acid through the catalyst bed in gaseous form at high temperature. The molar ratio of the catalyst was CaSO. 4 :Na 2 SO 4 =25:1 composite catalyst, the raw material is 10% lactic acid aqueous solution, the reaction temperature is 400℃, the normal pressure, the yield of acrylic acid is 54%; in 1988, the patent US4729978 reported a new supported catalyst, the main component is Na 2 HPO 4 The carrier is silica gel and alumina, gas-solid phase reaction, reaction temperature 350℃, normal pressure, acrylic acid yield is 58%; Patent US4786756 in 1988 uses NH 3 Treated AlPO 4 As a catalyst, the reaction temperature is 340℃, normal pressure, and the yield of acrylic acid is 43%. In 1993, US5252473 reported using CaSO 4 As a catalyst, the raw material is methyl lactate, the reaction temperature is 350-400°C, and the yield of methyl acrylate is 53%.

[0006] Summarizing the existing patented technology, it is found that the dehydration reaction of preparing acrylic acid series derivatives with lactic acid as the starting material has the following characteristics:

[0007] (1) The reaction temperature is higher than 300~500°C, which is mainly due to the higher activation energy of the reaction, and the reaction cannot proceed under low temperature conditions;

[0008] (2) The reaction is carried out under normal pressure. The main reason is that the acrylic acid series derivatives of the product contain C=C double bonds. At high temperatures, if there is a positive pressure, the possibility of polymerization and carbonization of acrylic acid derivatives is greatly increased;

[0009] (3) The reaction process is similar, and both adopt fixed-bed tubular reactors. The raw materials are pumped into the reaction tube in a liquid form by a micro pump to interact with the catalyst, and then leave the reactor, and cool and collect the discharged materials. Summary of the invention

[0010] The invention relates to a composition and preparation method of a catalyst for preparing acrylic acid and its butyl ester by dehydration of butyl lactate, so that the butyl lactate can be converted into acrylic acid and its butyl ester with high selectivity.

[0011] The catalyst of the present invention contains five components, namely A, B, C, D, E, A is the main catalyst is CaSO 4 , B, C, D, E are co-catalysts, among which: component B is sulfate, including: CuSO 4 , MgSO 4 , Na 2 SO 4 , NiSO 4 Any one or more of; C component is phosphate, including: Na 2 HPO 4 , NaH 2 PO 4 , KH 2 PO 4 , K 2 Any one or more of HPO4; D component is an alkaline substance, including: NaCO 3 , NaHCO 3 , La 2 O 3 , ThO 2 Any one or more of them; E is a forming aid, including: H 3 PO 4 , (NH 4 ) 3 PO 4 Any one or more of them. The molar ratios of the four co-catalysts B, C, D and E to the main catalyst A are respectively controlled at: B:A=1:100~1:20, C:A=1:100~1:20, D:A= 1:100~1:10, E:A=1:100~1:10.

[0012] The preparation method of the catalyst of the present invention is characterized as follows, and mainly has four steps:

[0013] (1) Weigh quantitative amounts of A, B, C, and D into the agate mortar to form a material system, grind it fully in a dry state, and then transfer the material system into a beaker;

[0014] (2) Dissolve component E in deionized water and add it to the material system (the amount of deionized water is equal to the total mass of components A, B, C, and D), stir it thoroughly, and place it in an oven at 110°C to dry until nothing Free water, get catalyst;

[0015] (3) Grind and pulverize the dried catalyst, sieving with 18-mesh and 35-mesh standard sieves, to obtain 18-35-mesh catalyst;

[0016] (4) Place the ground and sieved catalyst in a muffle furnace, roast it at 200-800°C for 2-10 hours, and place it in a desiccator for use after cooling.

[0017] The advantages of the present invention are:

[0018] ① The choice of the type and amount of the co-catalyst has a greater impact on the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester; it is mainly manifested in the following three aspects: First, the crystal form of the single-component main catalyst is long and coarse The columnar crystals are not conducive to the progress of the catalytic reaction. The addition of a co-catalyst can improve the crystal structure of the main catalyst, making the main catalyst appear as short columnar crystals, forming a multi-layered, porous catalytic structure, which is conducive to the progress of the reaction; second, The introduction of different types and quantities of co-catalysts is helpful to increase the conversion of raw materials and product selectivity; thirdly, the introduction of co-catalysts is helpful to increase the strength of the catalyst.

[0019] ②The catalyst prepared by the present invention belongs to the solid acid catalyst series. The solid acid catalyst has strong acid sites and weak acid sites. The addition of basic substance D shields some highly active strong acid site catalytic sites, which can inhibit the reaction from proceeding in depth. The selectivity of the butyl ester has a greater impact.

[0020] ③The amount of forming aid E has a direct effect on the strength of the entire catalyst. If the strength of the catalyst is too low, it is easy to collapse in the bed, causing the bed pressure drop to increase, and increasing the possibility of polymerization of the product acrylic acid and its butyl ester. Description of the drawings

[0021] figure 1 It is the SEM spectrum of the catalyst of Example 1.

[0022] figure 2 It is a data graph of the specific surface area of ​​the catalyst in Example 1.

[0023] image 3 It is the distribution diagram of the adsorption pore volume of the catalyst in Example 1.

[0024] Figure 4 It is the area distribution diagram of the adsorption pores of the catalyst in Example 1.

[0025] Specific implementation form

[0026] The following examples will further illustrate the present invention (the reagents used in the examples are chemically pure), but this does not limit the present invention.

[0027] Example 1:

[0028] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0029] Step 2: Put H 3 PO 4 Dissolved in quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of ), add it to the beaker in step 1, mix and stir thoroughly, the molar ratio of raw materials: CaSO 4 :H 3 PO 4 =50:2;

[0030] Step 3: Dry the material in step 2 in an oven at 110°C until there is no free water, grind and pulverize, sieving with a standard sieve of 18 mesh and 35 mesh to obtain a catalyst of 18 to 35 mesh;

[0031] Step 4: Roast the catalyst prepared in step 3 at 450°C for 4 hours, and place it in a desiccator for use after cooling;

[0032] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 77.6%, acrylic acid and its butyl ester The molar selectivity reached 70.8%.

[0033] Example 2:

[0034] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O3 =50:3:1:3;

[0035] Step 2 to Step 4: Same as Step 2 to Step 4 in Example 1.

[0036] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 75.7%, acrylic acid and its butyl ester The molar selectivity is 70.5%.

[0037] Example 3:

[0038] Step 1: Weigh a quantitative amount of CaSO 4 , MgSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :MgSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0039] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0040] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 69.1%, acrylic acid and its butyl ester The molar selectivity reached 65.1%.

[0041] Example 4:

[0042] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:3:3;

[0043] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0044] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 70.9%, acrylic acid and its butyl ester The molar selectivity is 68.2%.

[0045] Example 5:

[0046] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , KH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0047] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0048] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 77.5%, acrylic acid and its butyl ester The molar selectivity reached 65.9%.

[0049] Example 6:

[0050] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:5;

[0051] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0052] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 70.0%, acrylic acid and its butyl ester The molar selectivity reaches 60.0%.

[0053] Example 7:

[0054] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :NaHCO 3 =50:1:1:3;

[0055] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0056] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 72.3%, acrylic acid and its butyl ester The molar selectivity reached 66.8%.

[0057] Example 8:

[0058] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0059] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker of step 1, and fully mixed and stirred;

[0060] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0061] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 70.7%, acrylic acid and its butyl ester The molar selectivity is 60.9%.

[0062] Example 9:

[0063] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NiSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NiSO 4 :NaH 2 PO 4 :La 2 O 3 =50:0.5:0.5:1:3;

[0064] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NiSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker of step 1 and mixed thoroughly;

[0065] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0066] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 68.3%, acrylic acid and its butyl ester The molar selectivity is 68.1%.

[0067] Example 10:

[0068] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , MgSO 4 , Na 2 SO 4 , NaH 2 PO 4 , La 2 O 3, After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :MgSO 4 :Na 2 SO 4 :NaH 2 PO 4 :La 2 O 3 =50:0.5:0.5:0.5:1:3;

[0069] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , MgSO 4 , Na 2 SO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0070] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0071] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 71.3%, acrylic acid and its butyl ester The molar selectivity reached 64.1%.

[0072] Example 11:

[0073] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , Na 2 HPO 4 , KH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :Na 2 HPO 4 :KH 2 PO 4 :La 2 O 3 =50:1:0.5:0.5:0.5:3;

[0074] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , Na 2 HPO 4 , KH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0075] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0076] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 74.3%, acrylic acid and its butyl ester The molar selectivity is 59.6%.

[0077] Example 12:

[0078] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , ThO 2 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :NaHCO 3 :La 2 O 3 :ThO 2 =50:1:1:1:1:1;

[0079] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , ThO 2 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0080] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0081] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 66.3%, acrylic acid and its butyl ester The molar selectivity is 69.6%.

Examples

Embodiment 1

[0028] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0029] Step 2: Put H 3 PO 4 Dissolved in quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of ), add it to the beaker in step 1, mix and stir thoroughly, the molar ratio of raw materials: CaSO 4 :H 3 PO 4 =50:2;

[0030] Step 3: Dry the material in step 2 in an oven at 110°C until there is no free water, grind and pulverize, sieving with a standard sieve of 18 mesh and 35 mesh to obtain a catalyst of 18 to 35 mesh;

[0031] Step 4: Roast the catalyst prepared in step 3 at 450°C for 4 hours, and place it in a desiccator for use after cooling;

[0032] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its...

Embodiment 2

[0034] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O3 =50:3:1:3;

[0035] Step 2 to Step 4: Same as Step 2 to Step 4 in Example 1.

[0036] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 75.7%, acrylic acid and its butyl ester The molar selectivity is 70.5%.

Embodiment 3

[0038] Step 1: Weigh a quantitative amount of CaSO 4 , MgSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :MgSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0039] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0040] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 69.1%, acrylic acid and its butyl ester The molar selectivity reached 65.1%.

Technical field

[0001] The invention relates to the composition and preparation method of a catalyst for preparing acrylic acid by dehydration of butyl lactate and its butyl ester. Background technique

[0002] Acrylic acid and its butyl ester are basic organic chemical raw materials, and they are used in huge amounts in coatings, paints, adhesives, synthetic rubber, plastics, and water-absorbent resins. The preparation processes of acrylic acid and its butyl ester mainly include: cyanoethanol method, improved Reppe method, acrylonitrile hydrolysis method, and propylene oxidation method. The dominant one is the propylene oxidation method, which is currently used in 90% of operating devices.

[0003] The propylene oxidation method uses petroleum cracked product propylene as the raw material. The process is divided into two steps: the first step is to oxidize propylene to acrolein; in the second step, acrolein is further oxidized to acrylic acid. The raw material of the process comes from petroleum, which is not renewable. Resources will inevitably be exhausted in the foreseeable future, and world oil prices continue to rise. As of May 2008, oil prices have risen to 130 US dollars per barrel. With the continuous depletion of petroleum resources and the rise of oil prices, the source of raw materials for the production of acrylic acid and its butyl ester by propylene oxidation method has gradually decreased, and the production cost has continued to increase. However, the market demand for acrylic acid and its butyl ester has continued to increase. Solving this contradiction and exploring a new preparation process for acrylic acid and its butyl ester has become a top priority no matter from the perspective of future industry development or from the perspective of current actual industrial production.

[0004] Biological lactic acid is a typical renewable resource, which can be obtained through the fermentation of crops, and its process technology has been very mature. Lactic acid and acrylic acid have similarities in molecular structure, and the development of a process for preparing acrylic acid and its derivatives using biological lactic acid as the starting material has broad prospects.

[0005] In 1958, the patent US2859240 first reported the research work on the preparation of acrylic acid from lactic acid. The gas-solid phase reaction was adopted to realize the conversion of lactic acid to acrylic acid through the catalyst bed in gaseous form at high temperature. The molar ratio of the catalyst was CaSO. 4 :Na 2 SO 4 =25:1 composite catalyst, the raw material is 10% lactic acid aqueous solution, the reaction temperature is 400℃, the normal pressure, the yield of acrylic acid is 54%; in 1988, the patent US4729978 reported a new supported catalyst, the main component is Na 2 HPO 4 The carrier is silica gel and alumina, gas-solid phase reaction, reaction temperature 350℃, normal pressure, acrylic acid yield is 58%; Patent US4786756 in 1988 uses NH 3 Treated AlPO 4 As a catalyst, the reaction temperature is 340℃, normal pressure, and the yield of acrylic acid is 43%. In 1993, US5252473 reported using CaSO 4 As a catalyst, the raw material is methyl lactate, the reaction temperature is 350-400°C, and the yield of methyl acrylate is 53%.

[0006] Summarizing the existing patented technology, it is found that the dehydration reaction of preparing acrylic acid series derivatives with lactic acid as the starting material has the following characteristics:

[0007] (1) The reaction temperature is higher than 300~500°C, which is mainly due to the higher activation energy of the reaction, and the reaction cannot proceed under low temperature conditions;

[0008] (2) The reaction is carried out under normal pressure. The main reason is that the acrylic acid series derivatives of the product contain C=C double bonds. At high temperatures, if there is a positive pressure, the possibility of polymerization and carbonization of acrylic acid derivatives is greatly increased;

[0009] (3) The reaction process is similar, and both adopt fixed-bed tubular reactors. The raw materials are pumped into the reaction tube in a liquid form by a micro pump to interact with the catalyst, and then leave the reactor, and cool and collect the discharged materials. Summary of the invention

[0010] The invention relates to a composition and preparation method of a catalyst for preparing acrylic acid and its butyl ester by dehydration of butyl lactate, so that the butyl lactate can be converted into acrylic acid and its butyl ester with high selectivity.

[0011] The catalyst of the present invention contains five components, namely A, B, C, D, E, A is the main catalyst is CaSO 4 , B, C, D, E are co-catalysts, among which: component B is sulfate, including: CuSO 4 , MgSO 4 , Na 2 SO 4 , NiSO 4 Any one or more of; C component is phosphate, including: Na 2 HPO 4 , NaH 2 PO 4 , KH 2 PO 4 , K 2 Any one or more of HPO4; D component is an alkaline substance, including: NaCO 3 , NaHCO 3 , La 2 O 3 , ThO 2 Any one or more of them; E is a forming aid, including: H 3 PO 4 , (NH 4 ) 3 PO 4 Any one or more of them. The molar ratios of the four co-catalysts B, C, D and E to the main catalyst A are respectively controlled at: B:A=1:100~1:20, C:A=1:100~1:20, D:A= 1:100~1:10, E:A=1:100~1:10.

[0012] The preparation method of the catalyst of the present invention is characterized as follows, and mainly has four steps:

[0013] (1) Weigh quantitative amounts of A, B, C, and D into the agate mortar to form a material system, grind it fully in a dry state, and then transfer the material system into a beaker;

[0014] (2) Dissolve component E in deionized water and add it to the material system (the amount of deionized water is equal to the total mass of components A, B, C, and D), stir it thoroughly, and place it in an oven at 110°C to dry until nothing Free water, get catalyst;

[0015] (3) Grind and pulverize the dried catalyst, sieving with 18-mesh and 35-mesh standard sieves, to obtain 18-35-mesh catalyst;

[0016] (4) Place the ground and sieved catalyst in a muffle furnace, roast it at 200-800°C for 2-10 hours, and place it in a desiccator for use after cooling.

[0017] The advantages of the present invention are:

[0018] ① The choice of the type and amount of the co-catalyst has a greater impact on the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester; it is mainly manifested in the following three aspects: First, the crystal form of the single-component main catalyst is long and coarse The columnar crystals are not conducive to the progress of the catalytic reaction. The addition of a co-catalyst can improve the crystal structure of the main catalyst, making the main catalyst appear as short columnar crystals, forming a multi-layered, porous catalytic structure, which is conducive to the progress of the reaction; second, The introduction of different types and quantities of co-catalysts is helpful to increase the conversion of raw materials and product selectivity; thirdly, the introduction of co-catalysts is helpful to increase the strength of the catalyst.

[0019] ②The catalyst prepared by the present invention belongs to the solid acid catalyst series. The solid acid catalyst has strong acid sites and weak acid sites. The addition of basic substance D shields some highly active strong acid site catalytic sites, which can inhibit the reaction from proceeding in depth. The selectivity of the butyl ester has a greater impact.

[0020] ③The amount of forming aid E has a direct effect on the strength of the entire catalyst. If the strength of the catalyst is too low, it is easy to collapse in the bed, causing the bed pressure drop to increase, and increasing the possibility of polymerization of the product acrylic acid and its butyl ester. Description of the drawings

[0021] figure 1 It is the SEM spectrum of the catalyst of Example 1.

[0022] figure 2 It is a data graph of the specific surface area of ​​the catalyst in Example 1.

[0023] image 3 It is the distribution diagram of the adsorption pore volume of the catalyst in Example 1.

[0024] Figure 4 It is the area distribution diagram of the adsorption pores of the catalyst in Example 1.

[0025] Specific implementation form

[0026] The following examples will further illustrate the present invention (the reagents used in the examples are chemically pure), but this does not limit the present invention.

[0027] Example 1:

[0028] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0029] Step 2: Put H 3 PO 4 Dissolved in quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of ), add it to the beaker in step 1, mix and stir thoroughly, the molar ratio of raw materials: CaSO 4 :H 3 PO 4 =50:2;

[0030] Step 3: Dry the material in step 2 in an oven at 110°C until there is no free water, grind and pulverize, sieving with a standard sieve of 18 mesh and 35 mesh to obtain a catalyst of 18 to 35 mesh;

[0031] Step 4: Roast the catalyst prepared in step 3 at 450°C for 4 hours, and place it in a desiccator for use after cooling;

[0032] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 77.6%, acrylic acid and its butyl ester The molar selectivity reached 70.8%.

[0033] Example 2:

[0034] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O3 =50:3:1:3;

[0035] Step 2 to Step 4: Same as Step 2 to Step 4 in Example 1.

[0036] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 75.7%, acrylic acid and its butyl ester The molar selectivity is 70.5%.

[0037] Example 3:

[0038] Step 1: Weigh a quantitative amount of CaSO 4 , MgSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :MgSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0039] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0040] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 69.1%, acrylic acid and its butyl ester The molar selectivity reached 65.1%.

[0041] Example 4:

[0042] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:3:3;

[0043] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0044] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 70.9%, acrylic acid and its butyl ester The molar selectivity is 68.2%.

[0045] Example 5:

[0046] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , KH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0047] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0048] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 77.5%, acrylic acid and its butyl ester The molar selectivity reached 65.9%.

[0049] Example 6:

[0050] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:5;

[0051] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0052] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 70.0%, acrylic acid and its butyl ester The molar selectivity reaches 60.0%.

[0053] Example 7:

[0054] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :NaHCO 3 =50:1:1:3;

[0055] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0056] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 72.3%, acrylic acid and its butyl ester The molar selectivity reached 66.8%.

[0057] Example 8:

[0058] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0059] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker of step 1, and fully mixed and stirred;

[0060] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0061] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 70.7%, acrylic acid and its butyl ester The molar selectivity is 60.9%.

[0062] Example 9:

[0063] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NiSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NiSO 4 :NaH 2 PO 4 :La 2 O 3 =50:0.5:0.5:1:3;

[0064] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NiSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker of step 1 and mixed thoroughly;

[0065] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0066] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 68.3%, acrylic acid and its butyl ester The molar selectivity is 68.1%.

[0067] Example 10:

[0068] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , MgSO 4 , Na 2 SO 4 , NaH 2 PO 4 , La 2 O 3, After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :MgSO 4 :Na 2 SO 4 :NaH 2 PO 4 :La 2 O 3 =50:0.5:0.5:0.5:1:3;

[0069] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , MgSO 4 , Na 2 SO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0070] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0071] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 71.3%, acrylic acid and its butyl ester The molar selectivity reached 64.1%.

[0072] Example 11:

[0073] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , Na 2 HPO 4 , KH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :Na 2 HPO 4 :KH 2 PO 4 :La 2 O 3 =50:1:0.5:0.5:0.5:3;

[0074] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , Na 2 HPO 4 , KH 2 PO 4 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0075] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0076] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 74.3%, acrylic acid and its butyl ester The molar selectivity is 59.6%.

[0077] Example 12:

[0078] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , ThO 2 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :NaHCO 3 :La 2 O 3 :ThO 2 =50:1:1:1:1:1;

[0079] Step 2: Add quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , NaHCO 3 , ThO 2 , La 2 O 3 The total mass of) is added to the beaker in step 1, and mixed and stirred thoroughly;

[0080] Steps 3 to 4: Same as steps 3 to 4 in Example 1.

[0081] Step 5: Use the catalyst prepared in Step 4 in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 66.3%, acrylic acid and its butyl ester The molar selectivity is 69.6%.

Examples

Embodiment 1

[0028] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0029] Step 2: Put H 3 PO 4 Dissolved in quantitative deionized water (the amount of deionized water is CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 The total mass of ), add it to the beaker in step 1, mix and stir thoroughly, the molar ratio of raw materials: CaSO 4 :H 3 PO 4 =50:2;

[0030] Step 3: Dry the material in step 2 in an oven at 110°C until there is no free water, grind and pulverize, sieving with a standard sieve of 18 mesh and 35 mesh to obtain a catalyst of 18 to 35 mesh;

[0031] Step 4: Roast the catalyst prepared in step 3 at 450°C for 4 hours, and place it in a desiccator for use after cooling;

[0032] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its...

Embodiment 2

[0034] Step 1: Weigh a quantitative amount of CaSO 4 , CuSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :CuSO 4 :NaH 2 PO 4 :La 2 O3 =50:3:1:3;

[0035] Step 2 to Step 4: Same as Step 2 to Step 4 in Example 1.

[0036] Step 5: The catalyst prepared in Step 4 is used in the reaction of butyl lactate dehydration to prepare acrylic acid and its butyl ester, the specific reaction conditions: temperature 400℃, pressure at normal pressure, space velocity 1.8h -1 , Adopt nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, the experimental result: the molar conversion rate of butyl lactate reaches 75.7%, acrylic acid and its butyl ester The molar selectivity is 70.5%.

Embodiment 3

[0038] Step 1: Weigh a quantitative amount of CaSO 4 , MgSO 4 , NaH 2 PO 4 , La 2 O 3 , After being fully grinded in an agate mortar and transferred to a beaker, the molar ratio of raw materials: CaSO 4 :MgSO 4 :NaH 2 PO 4 :La 2 O 3 =50:1:1:3;

[0039] Step 2 to Step 4: Same as Steps 2 to 4 in Example 1.

[0040] Step 5: The catalyst prepared in step 4 is used in the dehydration reaction of butyl lactate to prepare acrylic acid and its butyl ester. The specific reaction conditions are: temperature 400℃, pressure is normal pressure, and space velocity is 1.8h -1 , Using nitrogen protection, the feed volume ratio of nitrogen and butyl lactate is: V (nitrogen): V (raw material) = 40:1, experimental results: the molar conversion rate of butyl lactate reaches 69.1%, acrylic acid and its butyl ester The molar selectivity reached 65.1%.

Claims

1. A kind of lactic acid method prepares the catalyst of acrylic acid and butyl ester, It is characterized in that, Contains five components, respectively the main catalyst A, co-catalysts B, C, D, E, of which: A is CaSO 4 ; B is a sulfate, including: CuSO 4 , MgSO 4 、Na 2 SO 4 、NiSO 4 Any one or more of them; the molar ratio of cocatalyst B and main catalyst A is: B:A=1:100~1:20; C is a phosphate, including: Na 2 HPO 4 , NaH 2 PO 4 、KH 2 PO 4 、K 2 Any one or more in HPO4; the molar ratio of cocatalyst C and main catalyst A is: C:A=1:100~1:20; D is an alkaline substance, including: NaCO 3 , NaHCO 3 , La 2 o 3 , ThO 2 Any one or more of them; the molar ratio of promoter D and main catalyst A is: D:A=1:100~1:10; E is a forming aid, including: H 3 PO 4 , (NH 4 ) 3 PO 4 Any one or more of them; the molar ratio of cocatalyst E and main catalyst A is: E:A=1:100~1:

10.

2. a kind of lactic acid method according to claim 1 prepares the catalyst of acrylic acid and butyl ester, It is characterized in that, Cocatalyst B is CuSO 4 , the molar ratio of cocatalyst B and main catalyst A is: B:A=1:

50.

3. a kind of lactic acid method according to claim 1 prepares the catalyst of acrylic acid and butyl ester, It is characterized in that, Cocatalyst C is NaH 2 PO 4 , the molar ratio of cocatalyst C and main catalyst A is: C:A=1:

50.

4. a kind of lactic acid method according to claim 1 prepares the catalyst of acrylic acid and butyl ester, It is characterized in that, Cocatalyst D is La 2 o 3 , the molar ratio of cocatalyst D and main catalyst A is: D:A=1:

50.

5. a kind of lactic acid method according to claim 1 prepares the catalyst of acrylic acid and butyl ester, It is characterized in that, Cocatalyst E is H 3 PO 4 , the molar ratio of cocatalyst E and main catalyst A is: E:A=1:

50.

6. prepare the method for the catalyst of acrylic acid and butyl esters prepared by a kind of lactic acid method described in claim 1, It is characterized in that, Contains the following steps: (1) Quantitative components A, B, C, and D are weighed and fully ground in an agate mortar in a dry state, and then the material is transferred into a beaker; (2) Dissolve component E in deionized water and add to the material system, wherein the amount of deionized water is equal to the total mass of components A, B, C, and D, and fully stirred, then dried in an oven at 110 ° C until nothing free water; (3) Grinding and pulverizing the dried catalyst, and sieving with a standard sieve to obtain a specific mesh catalyst; (4) The ground catalyst is placed in a muffle furnace, calcined at 200-800° C. for 2-10 hours, cooled and placed in a desiccator for use.

7. the preparation method according to claim 6, It is characterized in that, In the step (3), 18-mesh and 35-mesh standard sieves are selected for sieving to obtain a catalyst of 18-35 mesh.

8. the preparation method according to claim 6, It is characterized in that, The calcination temperature in the step (4) is 450°C, and the calcination time is 4h.

Images