Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for preparing dimethylamine from carbon dioxide, hydrogen and ammonia gas in one step

A carbon dioxide, dimethylamine technology, applied in chemical instruments and methods, reductive alkylation preparation, metal/metal oxide/metal hydroxide catalysts, etc., to achieve the effect of improving selectivity

Active Publication Date: 2019-12-13
NINGXIA UNIVERSITY
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Currently in industry CO 2 Catalytic hydrogenation to methanol and methanol amination to methylamine are relatively mature, and there is no CO 2 A Mature Route for One-step Synthesis of Methylamine by Catalytic Hydrogenation

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing dimethylamine from carbon dioxide, hydrogen and ammonia gas in one step
  • Method for preparing dimethylamine from carbon dioxide, hydrogen and ammonia gas in one step

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0026] Moreover, the Cu-based catalyst in the catalyst is expressed as Cu / M x o y , M is ZnO, Al 2 o 3 、Cr 2 o 3 , ZrO 2 , SiO 2 、TiO 2 One or more of them, preferably ZnO, Al 2 o 3 、Cr 2 o 3 , ZrO 2 , the catalyst is prepared by a co-precipitation method, and the steps of the preparation method are as follows:

[0027] (1) According to the element molar ratio Cu:M=1:1-10, prepare salt solution A containing Cu and M elements, M nitrate solution, preferably containing ZnO and Al 2 o 3 、Cr 2 o 3 , ZrO 2 elemental salt solutions;

[0028] (2) After mixing, stir for 10-60 minutes;

[0029] (3) The preparation is selected from NaOH, Na 2 CO 3 Compound aqueous solution or ammonia solution B, at 100-500r / min speed, water bath temperature 50-90℃, mix A and 0.5-5mol / LB evenly, control pH=8-14, keep stirring until precipitation is complete, precipitation After aging for 2-48h, wash with deionized water;

[0030](4) Drying at 60-120°C for 5-24h, calcining at 350-500...

Embodiment 1

[0037] (1) According to the elemental molar ratio Cu:Zn:ZrO 2 =10:5:1 Weigh copper nitrate, zinc nitrate, zirconium nitrate, prepare a solution with a solid-to-liquid ratio of 1:5, dissolve and stir for 60 minutes; add 1 mol / L of NaOH solution, control pH = 10; continue to stir for 2 hours after the dropwise addition, and age overnight; dry at 100°C for 15 hours, roast at 350°C, grind, granulate to 20-40 mesh, set aside, record as Q;

[0038] (2) Molecular sieve H-ZSM-5 raw material molar ratio TEOS:TPAOH:H 2 O:EtOH:Al 2 o 3 =2:0.68:120:8:0.24. After the mixed solution forms a gel, record it as W; add 20-40 mesh Cu-based catalyst Q to the above mother liquor, mix according to the ratio of mass Q:W=3:1; stir at room temperature for 2 hours, and then transfer to polytetrafluoroethylene In a lined stainless steel reactor, at 160°C, with a rotation speed of 2rpm / min, crystallize for 24h, filter off the mother liquor, centrifuge, wash, dry, and roast at 550°C for 5h to obtain ...

Embodiment 2

[0040] Cu base catalyst preparation step is the same as embodiment 1 (1), molecular sieve SAPO-34 raw material molar ratio is Al 2 o 3 :P 2 o 5 :SiO2 2 :TEAOH:H 2 O=1:1:0.6:2:110. After the mixed solution forms a gel, the preparation process of the core-shell structure catalyst is the same as that in Example 1(2), mixing according to the ratio of mass Q:W=3:1. The crystallization conditions were 200°C, the rotation speed was 2rpm / min, the crystallization time was 24h, and the catalyst was roasted at 550°C for 5h to obtain the product catalyst CuZnZr@SAPO-34 (3:1); see Table 1 and Example 2 for the catalytic reaction results. The reaction condition is H 2 / CO 2 / NH 3 =1:1:3, the reaction temperature is 400°C, and the reaction pressure is 1.5MPa.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a method for preparing dimethylamine from carbon dioxide, hydrogen and ammonia gas in one step. The method is characterized by comprising the following steps: the dimethylamine is prepared in one step by taking the carbon dioxide, hydrogen and ammonia gas as reaction raw materials according to the chemical reaction formula of 2CO2+ 6H2 + NH3=(CH3)2NH + 4H2O, wherein the molar ratio of H2 to CO2 to NH3 of the raw materials is (1-3): 1:(1-3); the reaction temperature is 200-400 DEG C, the reaction pressure is 0.1-5 MPa, the reaction raw materials carry out contact reaction through a core / shell catalyst bed layer in a fixed bed reactor to prepare the dimethylamine in one step, and a reaction catalyst consists of a catalyst for preparing methanol by catalytic hydrogenation of carbon dioxide and a catalyst for preparing methylamine by amination of methanol. The technology is realized in the fixed bed reactor, the CO2, the H2 and the NH3 are selectively synthesized into the dimethylamine, the reaction raw materials are subjected to contact reaction through the core / shell catalyst bed layer in the fixed bed reactor to prepare the dimethylamine in one step, and thereaction catalyst comprises the catalyst for preparing methanol by catalytic hydrogenation of carbon dioxide and the catalyst for preparing methylamine by amination of methanol, and the process flowis simple, energy is saved, and consumption is reduced.

Description

technical field [0001] The invention belongs to the field of chemical synthesis, and relates to a method for preparing a multifunctional core / shell catalyst, in particular to a method for preparing dimethylamine in one step from carbon dioxide, hydrogen and ammonia. Background technique [0002] Methylamine includes monomethylamine (MMA), dimethylamine (DMA) and trimethylamine (TMA). It is an important class of fine organic chemical raw materials. It is used in the synthesis of pesticides, medicines, national defense chemicals, dyes, and surfactants. multiple usage. Among them, dimethylamine can synthesize dimethylformamide, and the market demand is the largest, and the supply exceeds the demand. In industry, the methanol amination method is used to synthesize the crude products of monomethylamine, dimethylamine and trimethylamine with methanol and ammonia as raw materials under high temperature, high pressure and the presence of aluminosilicate catalysts, and then separate...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C07C209/26C07C211/04B01J29/46B01J29/85B01J29/14B01J29/76B01J23/80
CPCC07C209/26B01J29/46B01J29/85B01J29/146B01J29/76B01J23/80B01J35/398B01J35/19C07C211/04Y02P20/584
Inventor 高新华陈国辉赵太奇赵天生张建利马清祥范素兵
Owner NINGXIA UNIVERSITY