Precious Metal Refining
Current position:
Evaluation of Catalyst
Precious metal catalysts are mainly platinum (Pt), palladium (Pd), rhodium (Rh), ruthenium (Ru), iridium (Ir), osmium (Os), etc. mainly based on platinum group metals (Platinum Group Metal) It is a kind of heterogeneous catalyst of carrier type which is a catalytically active component and various types of homogeneous catalysts composed of platinum group metal inorganic compounds or organic complex metal compounds. Platinum group metals are not filled with d electron orbits, the surface is easy to adsorb reactants, and the strength is moderate, which is conducive to the formation of intermediate "active compounds", has high catalytic activity, and also has high temperature resistance, oxidation resistance, corrosion resistance, etc. Comprehensive excellent characteristics, become the most important catalyst material.

According to the type of catalytic reaction, precious metal catalysts can be divided into two categories: homogeneous catalysis and heterogeneous catalysis. Catalysts for homogeneous catalysis are usually soluble compounds (salts or complexes), such as palladium chloride, rhodium chloride, palladium acetate, rhodium carbonyl, triphenylphosphine rhodium carbonyl, rhodium iodide, and the like. The catalyst for heterogeneous catalysis is an insoluble solid, and its main forms are a wire mesh state and a porous inorganic carrier supported metal state. Metal wire mesh catalysts (such as platinum mesh, platinum rhodium alloy mesh, etc.) have limited application scope and dosage. Most heterogeneous catalysts are supported by precious metals, such as Pt/A12O3, Pd/C, Rh/SiO2, Pt-Pd/Al2O3, Pt-Rh/Al2O3, etc. In all catalytic reactions, heterogeneous catalytic reactions account for 80% to 90%. According to the shape of the carrier, the supported catalyst can be divided into particulate, spherical, columnar and honeycomb. According to the main active metals of catalysts, platinum catalysts, palladium catalysts, rhodium catalysts and ruthenium catalysts are commonly used. Noble metal catalysts are highly valued for their excellent activity, selectivity, and stability. They are widely used in reactions such as hydrogenation, dehydrogenation, oxidation, reduction, isomerization, aromatization, cracking, and synthesis. , Petrochemistry, medicine, environmental protection and new energy, automobile exhaust emission control and other fields play a very important role.

The main application performance indicators of the catalyst are as follows: (1) Activity. It is a standard to measure the efficiency of the catalyst. In industry, it is usually expressed by the number of products per unit time (or weight) of the catalyst under certain conditions per unit time. (2) Selectivity. Refers to the specificity of the role of the catalyst, that is, under certain conditions, a certain catalyst only accelerates a certain chemical reaction. The selectivity is usually expressed as a percentage of the ratio of the moles of the expected product obtained after the reaction to the moles of the raw materials participating in the reaction. (3) Stability. Refers to the ability of the catalyst to maintain its activity and selectivity during use, usually expressed in terms of service life. The good performance of the catalyst depends not only on the inherent characteristics of the active metal (atomic electronic structure, etc.), but also on its crystal structure, particle size, specific surface area, pore structure and dispersion state. In addition, co-catalysts and supports also have an important effect on the performance of the catalyst.

Evaluation of performance characterization of common precious metal catalyst materials

Zhejiang Mircro General New Catalytic Material Co., Ltd. can provide customers with physical and chemical performance testing research and services related to precious metal compounds. Establish a fully automatic catalytic performance evaluation device to carry out evaluation research and services such as catalytic activity, selectivity, and stability. Use the instrument to accurately analyze the content of precious metals, catalyst structure and phase structure characteristics of various compounds; and the molecular structure, active components, surface composition, adsorption state, catalytic mechanism, catalytic kinetics of the catalyst, and use the catalytic performance evaluation device Carry out catalyst performance research, etc.

Application test of precious metal catalyst selection

According to the different reaction types of catalysts used by catalyst customers, the research and development department of Weitong Company can use existing organic synthesis equipment for catalyst evaluation and selection, provide customers with efficient and suitable catalyst varieties, and can provide customers with the following types of reaction catalyst selection tests :
(1) Catalytic hydrogenation reaction
(2) Catalytic hydrogenolysis reaction
(3) Cross-coupling reaction
Catalyst Recycling

Zhejiang Mircro General New Catalytic Material Co., Ltd has the "Hazardous Waste Business License" issued by the Zhejiang Provincial Department of Ecology and Environment, which can provide customers with the disposal and recycling services of waste catalysts containing precious metals. Through recycling and processing, the precious metals in the waste catalysts can be realized Reuse can save the cost of using catalysts for customers, and can comprehensively dispose, recycle and recycle platinum, palladium, rhodium series metals in the following materials:

(1) Noble metal-containing waste catalysts produced in the manufacture of basic chemical raw materials;
(2) Precious metal-containing waste catalysts produced during the production of pesticides and veterinary drugs;
(3) Noble metal-containing waste catalysts produced during the production of chemically synthesized APIs;
(4) Invalid petrochemical catalyst;
(5) Precious metal-containing waste catalysts produced in other non-specific industries;
(6) Other complex precious metal scrap.

The precious metals used in the catalyst all have strict impurity requirements. The use of precious metals with impurities exceeding the standard will affect the performance of the catalyst, and even poison the catalyst and inactivate it. The use of precious metals in general catalyst processing requires a purity of more than 99.95%, and requires no specific metal impurities that affect the catalytic activity.

Zhejiang Mircro General New Catalytic Material Co., Ltd has introduced the precious metal research and development team of Zhejiang Provincial Metallurgical Research Institute. It has more than 20 years of experience in precious metal refining and purification. It is equipped with various precious metal and impurity analysis and detection equipment. The precious metal scrap is purified and refined, and the purified precious metal can reach more than 99.99%.