What are the types of hair boosters? What are the industrial catalysts?

There are many types of catalysts, which can be divided into liquid catalysts and solid catalysts according to their states; According to the phase state of the reaction system, it can be divided into homogeneous catalysts and heterogeneous catalysts, and homogeneous catalysts include acids, alkalis, soluble transition metal compounds and peroxides.

Catalyst. Heterogeneous catalysts include solid acid catalysts, organic alkali catalysts, metal catalysts, metal oxide catalysts, complex catalysts, rare earth catalysts, molecular sieve catalysts, biological catalysts, nanocatalysts, etc.; According to the type of reaction, it is divided into polymerization, polycondensation, esterification, acetalization, hydrogenation, dehydrogenation, oxidation, reduction, alkylation, isomerization and other catalysts; According to the size of the action, it is also divided into main catalyst and co-catalyst.

Catalytic reactions have four basic characteristics that can be derived from the definition and are important to understand the function of a catalyst:

1. Catalysts can only accelerate thermodynamics.

can carry out Zheng Zhen's reaction. When a new chemical reaction catalyst is required, the first step is to perform a thermodynamic analysis of the reaction to see if it is a thermodynamically feasible reaction.

2. The catalyst can only accelerate the reaction to equilibrium, and cannot change the equilibrium position of the reaction (equilibrium constant.

3. The catalyst is selective to the reaction, when the reaction may have more than one different direction, the catalyst only accelerates one of them, and the promotion reaction rate and selectivity are unified.

4. The life of the catalyst. Catalysts can change the rate of chemical reactions.

It does not enter the reaction on its own, and ideally the catalyst is not altered by the reaction. However, in the actual reaction process, the catalyst will be subjected to long-term heating and chemical reactions, and some irreversible physical and chemical changes will also occur.

The above content reference: Encyclopedia - Catalyst.

The types of catalysts are:

1. According to the state, it can be divided into liquid catalyst and solid catalyst.

2. According to the phase state of the reaction system, it is divided into homogeneous catalyst and heterogeneous catalyst, and the homogeneous catalyst includes acid, alkali, soluble transition metal compound and peroxide catalyst.

Heterogeneous catalysts include solid acid catalysts, organic alkali catalysts, metal catalysts, metal oxide catalysts, complex catalysts, rare earth catalysts, molecular sieve catalysts, biological catalysts, nanocatalysts, etc.

3. According to the type of reaction, it is divided into polymerization, polycondensation, esterification, acetalization, hydrogenation, dehydrogenation, oxidation, reduction, alkylation, isomerization and other catalysts.

4. According to the size of the action, it is also divided into main catalyst and co-catalyst.

Uses of catalysts:

Catalysts have an important and wide range of applications in chemical production, and catalysts are used in the production of chemical fertilizers, pesticides, and a variety of chemical raw materials.

Catalysts are widely used in all walks of life around the world, and in the future, there are great prospects for development in the scientific and theoretical research of catalysts, the development and utilization of clean energy, environmental protection and economic improvement, and the governance and protection of the human living environment.

In short, the survival and development of human beings, food, clothing, housing and transportation are inseparable from catalysts and their development.

The catalysts commonly used in the esterification reaction in the factory are:Concentrated sulfuric acid, concentrated hydrochloric acid, p-toluenesulfonic acid,Thionyl chloride

in absolute ethanol and glacial acetic acid.

Reaction to make ethyl acetate.

In the experiment, concentrated sulfuric acid is used as a catalyst and a water-absorbing agent, and the catalytic mechanism is hydrogen ion polarization carbonyl.

, enhancing the ability of carbonyl C to be attacked by nucleophiles.

There are many catalysts commonly used in industry, such as: pentoxene hail used to catalyze sulfur dioxide in the sulfuric acid industry, vanadium rentalization, ammonia catalytic oxidation to nitric oxide.

Platinum rhodium alloy is used as a catalyst, iron catalyst (iron-based metal) is used in the ammonia industry, nickel or platinum is used for dehydrogenation and hydrogenation in the petrochemical industry, rhenium for catalytic reforming, etc.

Other Definitions. There is also a saying that tung catalysts are involved in chemical reactions. In a total chemical reaction, the role of the catalyst is to reduce the activation energy required for the reaction to occur, essentially turning a relatively difficult reaction into two chemical reactions that can easily occur (the opposite is called an inhibitor).

In these two reactions, the catalyst plays the role of reactant in the first reaction, and the catalyst plays the role of product in the second reaction, so in terms of the overall reaction equation, the catalyst does not change before and after the reaction.

Several common catalysts: 1Catalysts, such as platinum, palladium, rhodium and other metals and their oxides, hydroxides, etc., are often used in automobile exhaust purification, organic chemical synthesis and other fields; 2.

Enzyme catalysts, such as proteases, cellulases, amylases, etc., are commonly used in food, pharmaceutical, winemaking and other fields; 3.Acid catalysts, such as sulfuric acid, salt slow acid, phosphoric acid, etc., are commonly used in hydrophobic modification of oils and fats, saccharification reactions, cracking and other fields; 4.Alkali catalysts, such as sodium hydroxide, potassium hydroxide, etc., are commonly used in soap manufacturing, biofuel chemical reactions, colloidal electrophoresis and other fields; 5.

Oxidation catalysts, such as hydrogen peroxide, potassium permanganate, etc., are commonly used in organic chemical synthesis, environmental pollution control and other fields. A catalyst is a substance that accelerates the rate of a chemical reaction without changing the thermodynamic properties of the reaction. Catalysts can play a role in reducing activation energy, increasing reaction rate, and changing reaction paths in chemical reactions.

Different catalysts have the catalytic effect and application value of special cracking hail determination in different chemical reactions. <>