This article briefly describes the meaning of hydrogenation and classifications of hydrogenation reaction equipment. Those who are interested in hydrogenation can use this as a basis to explore further in the field of hydrogenation.
Hydrogenation is the reaction of an organic compound with molecular hydrogen, usually with a catalyst.
I, Classifications of hydrogenation as per reaction feature
(1)Add hydrogen
Increase the number of hydrogen atoms in the molecule of an unsaturated organic compound to make it a relatively saturated organic compound.
For example, unsaturated fats and oils (such as cottonseed oil, fish oil, etc.) can be changed to saturated hardened oil after hydrogenation.
Benzene is hydrogenated to produce cyclohexane, which is used in the manufacture of polyamide;
Manufacture of synthetic lubricants, soap, glycerol process is also a hydrogenation process.
(2) Hydrolysis
Also known as the Destruction Of Hydrogenation. The reaction goes with the organic molecules rupture and hydrogen atoms increasing simultaneously.
For example, coal dust, heavy petroleum fractions, coal tar, and shale oil by hydrogenolysis, into small molecules of liquid state of margarine, by fractionation can be obtained by artificial gasoline.
II, Difference between hydrogenation and synthesis
Hydrogenation is a chemical reaction between the organic substance and hydrogen.
Synthesis is a reaction between inorganic substances and hydrogen, such as nitrogen and hydrogen to generate ammonia, carbon monoxide reacts with hydrogen to make methanol.
III, The core equipment required by the hydrogenation reaction
The hydrogenation reactor is the core equipment of the hydrogenation plant and the key to the hydrogenation process.
IV, Classification of hydrogenation as per apparatus used
| No. |
Phase |
apparatus name class1. |
apparatus class 2 |
apparatus class 3
|
| 1 |
Liquid-phase hydrogenation
|
Batch liquid-phase hydrogenation
|
Pressure kettle with stirring device |
| Bubbling reactor hydrogenation |
Bubble columns |
| Bubble stirring kettle reactor |
| Continuous liquid-phase hydrogenation |
/ |
/ |
| 2 |
Gas-phase continuous hydrogenation |
Column hydrogenation |
/ |
/ |
| Tower Hydrogenation |
/ |
/ |
1、Liquid-phase hydrogenation reactor
This type of reactor is used for liquid-phase hydrogenation processes of high-boiling-point liquids or solids (solids need to be dissolved in a solvent or heated and melted first) feedstocks, such as the hydrogenation of fats and oils, and the hydrocracking of heavy oils.
The reaction is often carried out under pressure, the process can be carried out in a Batch reaction or a Continuous Reactor.
1.1, Batch liquid-phase hydrogenation
It is often used with a stirring device pressure reaction kettle or bubble reactor.
1.1.1 Pressure kettle with stirring device
Samples of Pressure Kettle with Stirring Device:
 |
 |
| Industrial batch pressurized hydrogenation reactor. |
lab pressurized hydrogenation reactor |
1.1.2 Bubbling reactor
The bubbling reactor is a gas-liquid reactor with the liquid phase as the continuous phase and the gas phase as the dispersed phase.
1.1.2.1 Device characteristics
The main features of the drum bubble reactor are a high liquid phase volume fraction (up to 90% or more) and a small phase boundary area per unit volume of liquid phase (below 200m2/m3).
When the reaction is very slow, the process is controlled by the liquid phase reaction, to improve the reaction rate based on the unit reactor volume mainly by increasing the liquid phase volume fraction, it is appropriate to use the bubbling reactor.
When the reaction is very fast, the process is controlled by the gas-liquid interphase mass transfer, to improve the process rate mainly by increasing the phase boundary area, it is appropriate to use the filled tower or plate tower.
1.1.2.2 Types of Bubbling Reactors
1.1.2.2.1 Bubble columns
Liquid is added in batches and gas is fed continuously in what is known as a semi-continuous operating bubble tower.
Continuously operated bubbling towers gas and liquid are constantly added, and the direction of flow can be upward and parallel or countercurrent.
1.1.2.2.2 Bubble stirring kettle reactor
Also called aeration stirring kettle, the use of mechanical stirring to make the gas dispersion into the liquid stream to achieve mass transfer and chemical reaction.
The commonly used stirrer is the turbine stirrer, and the gas distributor is installed in the center under the stirrer.
Bubble stirring kettle because the form, number, size, installation position, and speed of the stirrer can be selected and adjusted, so it has a strong adaptability.
Most of the continuous hydrogenation reactors system made by WHGCM could be sorted as bubble stirring kettle reactors.
 |
This is typical bubble stirring kettle reactor.
It has an inlet liquid port for continuous feeding of the reactant.
The PLC cabinet monitors and controls the flow rate, stirring speed, and temperature so as to make sure the reaction is under control. |
1.2, Continuous liquid-phase hydrogenation
It can be used as a trickle bed reactor or gas, liquid, solid three-phase continuous flow of tubular reactor.
2, Gas-phase continuous hydrogenation
Another type of reactor is used for gas-phase continuous hydrogenation processes, such as atmospheric pressure gas-phase hydrogenation of benzene to make cyclohexane, high-pressure gas-phase hydrogenation of carbon monoxide to synthesize methanol, etc., and the type of reactor can be either column or tower.
