CN103664634B - For loaded catalyst prepared by 1,2 propane diamine - Google Patents

Abstract

The invention discloses a type of supported catalyst. The catalyst is used to catalyze the preparation of 1,2-propylenediamine. The main synthesis steps are as follows: add 1,2-dichloropropane, ammonia water, and the supported catalyst into the reaction kettle, and the reaction kettle Rotating at a uniform speed in a homogeneous reactor, the amination reaction is carried out at a reaction temperature of 140° C. to 170° C. to prepare 1,2-propylenediamine, and the yield of the product is higher than 65%. After the reaction finishes, first remove the unreacted ammonia, and then obtain the aqueous solution of 1,2-propylenediamine by atmospheric distillation. Advantages of the present invention: (1) the supported catalyst catalyzes the preparation of 1,2-propylenediamine, and obtains a higher yield; (2) adopts the by-product 1,2-dichloropropane produced in the process of producing chloropropene as The raw materials greatly reduce the production cost; (3) the reaction process is simple and the operation is convenient; (4) the method is safe and environment-friendly, and is beneficial to industrialized production.

Description

Supported Catalyst for Preparation of 1,2-Propanediamine

Technical field:

The invention belongs to the technical field of chemical synthesis, relates to the preparation of a class of supported catalysts, and uses the catalysts to catalyze the synthesis of 1,2-propanediamine.

technical background:

1,2-Propylenediamine is an important organic chemical intermediate and raw material. Its applications include the production of beneficiation agents, metal deactivators, and aviation resin curing agents; in the production of rubber vulcanization accelerators Also has a certain use value; at the same time, 1,2-propylenediamine is also used in dyes, electroplating and reagents for analyzing metals (in the determination of elements such as mercury, copper and silver); for the production of 1,2-propylenediaminetetraacetic acid ; Use in pharmaceuticals, including as an intermediate in the production of propylene imine anticancer drugs.

At present, with the gradual expansion of the scope of application of 1,2-propanediamine, its market demand also increases. Global demand is in the thousands of tons. So far, most of the domestic 1,2-propylenediamine products are imported from BASF. The domestic traditional process uses 1,2-dichloropropane as a raw material to synthesize 1,2-dichloropropane through amination reaction. As far as the applicant knows, the product yield of this route is lower than 50%.

The reason why the reaction yield of dichloropropane is low is that the specific surface area of the granular catalyst is small and the active sites provided are few. As a result, the reaction is insufficient and rapid, causing more side reactions. By dispersing the active components of the catalyst on the carrier with a large specific surface area, the catalytic activity of the catalyst is improved as a whole, which is beneficial to the improvement of the conversion rate of raw materials and the selectivity in the reaction.

Contents of the invention

The invention prepares a type of supported catalyst, which aims to disperse the active components of the catalyst on the surface by virtue of the large specific surface area of the carrier, thereby increasing the dispersion of the active components and increasing the active sites of catalysis. The catalyst is used to catalyze the amination reaction of 1,2-dichloropropane to prepare 1,2-propanediamine. The catalyst has high catalytic activity, which improves the yield of products to a great extent.

The process of this experiment is: add 1,2-dichloropropane, ammonia water, and supported catalyst into the reactor, and the reactor is rotated at a constant speed in a homogeneous reactor, and reacted at 140°C to 170°C for 1h to 4h. The reaction equation is as follows:

The active component of the catalyst is CuO, and its carrier is nano or micron SiO ₂ , TiO ₂ , Al ₂ O ₃ , ZrO ₂ powder or their composites, and the proportion of the active component is 5% to 5%. 20%. It is a black powder catalyst prepared by impregnation precipitation method, co-precipitation method, sol-gel method, hydrolysis precipitation method, hydrothermal method, reverse micellar method, spraying method, and then dried and calcined.

The molar ratio of the 1,2-dichloropropane to ammonia is 1:10-40, and the amount of the catalyst is 1%-20% of the mass of the 1,2-dichloropropane.

The reaction temperature of the present invention is 140°C-170°C; the reaction time is 1h-4h.

Compared with the existing technology, the present invention has the following advantages: (1) the supported catalyst catalyzes the preparation of 1,2-propylenediamine and obtains a higher yield; (2) adopts the by-product produced in the process of producing chloropropene The product 1,2-dichloropropane is used as a raw material, which greatly reduces the production cost; (3) the reaction process is simple and the operation is convenient; (4) the method is safe and environment-friendly, and is beneficial to industrial production.

detailed description:

Comparative example 1

Add 10 mL of 1,2-dichloropropane, 0.05 g of CuO, and 100 mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. The temperature was lowered to room temperature, unreacted ammonia gas was removed, and gas chromatography was used to detect that the yield of 1,2-propanediamine was 40%.

Comparative example 2

Add 5mL of 1,2-dichloropropane, 0.5g of CuO, and 100mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. The temperature was lowered to room temperature, unreacted ammonia gas was removed, and gas chromatography was used to detect that the yield of 1,2-propanediamine was 47.05%.

Example 1

Accurately weigh 1g of SiO ₂ and suspend it in 20mL of distilled water, then weigh 0.3196g of CuCl ₂ ·2H ₂ O, add it to the suspension, and ultrasonically disperse the SiO ₂ for 30min. Heat the mixed solution after ultrasonication at 100°C until the solution is evaporated to dryness, then transfer it to an incubator at 120°C for 2 hours, and finally transfer it to a muffle furnace for calcination at 400°C for 3 hours . The prepared catalyst CuO/ _SiO2 was used for the next catalytic reaction. The content of CuO is 15% of the weight of the carrier. Add 5 mL of 1,2-dichloropropane, 0.5 g of CuO/SiO ₂ , and 100 mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. The temperature was lowered to room temperature, unreacted ammonia gas was removed, and gas chromatography was used to detect that the yield of 1,2-propanediamine was 64.72%.

Example 2

Accurately weigh 1g TiO ₂ and suspend it in 20mL of distilled water, then weigh 0.3196g CuCl ₂ ·2H ₂ O, add it to the suspension, and ultrasonically disperse the TiO ₂ uniformly for 30min. Heat the mixed solution after ultrasonication at 100°C until the solution is evaporated to dryness, then transfer it to an incubator at 120°C for 2 hours, and finally transfer it to a muffle furnace for calcination at 400°C for 3 hours . The prepared catalyst CuO/ _TiO2 was used for the next catalytic reaction. The content of CuO is 15% of the weight of the carrier. Add 5 mL of 1,2-dichloropropane, 0.5 g of CuO/TiO ₂ , and 100 mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. The temperature was lowered to room temperature, unreacted ammonia gas was removed, and gas chromatography was used to detect that the yield of 1,2-propanediamine was 66.03%.

Example 3

Accurately weigh 1g of Al ₂ O ₃ and suspend it in 20mL of distilled water, then weigh 0.3196g of CuCl ₂ 2H ₂ O, add it to the suspension, and ultrasonicate the mixture for 30min to remove Al ₂ O ₃ Evenly dispersed. Heat the mixed solution after ultrasonication at 100°C until the solution is evaporated to dryness, then transfer it to an incubator at 120°C for 2 hours, and finally transfer it to a muffle furnace for calcination at 400°C for 3 hours . The prepared catalyst CuO/Al ₂ O ₃ is used for the next catalytic reaction. The content of CuO is 15% of the weight of the carrier. Add 5 mL of 1,2-dichloropropane, 0.5 g of CuO/Al ₂ O ₃ , and 100 mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. Cool down to room temperature, remove unreacted ammonia gas, and detect by gas chromatography, the yield of 1,2-propanediamine is 68.39%.

Example 4

Accurately weigh 1g of ZrO ₂ and suspend it in 20mL of distilled water, then weigh 0.3196g of CuCl ₂ ·2H ₂ O, add it to the suspension, and ultrasonically disperse the ZrO ₂ for 30min. Heat the mixed solution after ultrasonication at 100°C until the solution is evaporated to dryness, then transfer it to an incubator at 120°C for 2 hours, and finally transfer it to a muffle furnace for calcination at 400°C for 3 hours . The prepared catalyst _CuO /ZrO2 was used for the next catalytic reaction. The content of CuO is 15% of the weight of the carrier. Add 5 mL of 1,2-dichloropropane, 0.5 g of CuO/ZrO ₂ , and 100 mL of ammonia water into the reaction kettle. The reaction kettle was put into a homogeneous reactor and rotated at a constant speed, and the temperature was raised to 160° C. for 3 hours. Cool down to room temperature, remove unreacted ammonia gas, and detect by gas chromatography, the yield of 1,2-propanediamine is 66.16%.

Claims (6)

1. A catalytic synthesis method for 1,2-propanediamine, characterized in that: take 1,2-dichloropropane as raw material, add ammoniacal liquor and loaded catalyst in the reactor simultaneously, at a temperature of 140°C to 170°C Carry out amination reaction and synthesize 1,2-propanediamine below, and its reaction equation is as follows: The supported catalyst uses CuO as the active component and SiO ₂ , TiO ₂ , Al ₂ O ₃ , ZrO ₂ as the carrier, and the carrier is selected from nano or micron SiO ₂ , TiO ₂ , Al ₂ O ₃ , ZrO ₂ Powder or their composites are prepared by dipping precipitation method, co-precipitation method, sol-gel method, hydrolysis precipitation method, hydrothermal method, reverse micellar method, spray method, and then dried and calcined. A black powder catalyst; The dosage of the active component CuO in the supported catalyst is 5%-20% of the weight of the carrier. 2. the catalyzed synthesis of 1,2-propanediamine as claimed in claim 1, is characterized in that: the mol ratio of 1,2-dichloropropane and ammonia is 1: 10～40. 3. The catalytic synthesis of 1,2-propanediamine as claimed in claim 1, characterized in that: in the first step, the consumption of the catalyst is 1,2-dichloropropane mass of 1% to 20%. 4. The catalytic synthesis of 1,2-propanediamine as claimed in claim 1, characterized in that: the calcination temperature of the catalyst is 200°C-500°C. 5. The catalytic synthesis of 1,2-propanediamine as claimed in claim 1, characterized in that: the calcination time of the catalyst is 2h-5h. 6. The catalytic synthesis of 1,2-propanediamine as claimed in claim 1, characterized in that: the reaction time is 1h～4h.