Non-crystalline alloy catalyst of uniform grain size and its preparing method

Abstract

The present invention discloses non-crystalline alloy catalyst of uniform grain size and its preparation process. The catalyst is spherical grains of size in 10-500 nm. The preparation process includes: mixing metal salt solution and ligand solution well to form stable metal complex, adding reductant to obtain homogeneously mixed solution, ultrasonic initiation of reduction in the solution to obtain black solid, and washing separately with deionized water and absolute ethyl alcohol to obtain the non-crystalline alloy catalyst of uniform grain size. The said preparation process can maintain the high homogeneity and dispersion of the metal salt and reductant components, so as to prepare high performance non-crystalline alloy with uniform grain size. The catalyst may be used in hydrogenating various compounds with unsaturated functional radical and has hydrogenating performance superior to non-crystalline alloy prepared through conventional chemical reduction process.

Description

technical field [0001] The invention relates to an amorphous alloy catalyst with uniform particle size, in particular to a narrow distribution amorphous alloy catalyst and a preparation method thereof. Background technique [0002] Amorphous alloy means that the atoms or their mixed arrangement that make up the alloy are completely disordered, and there is no periodicity and translation in space. Therefore, amorphous alloys are a type of long-range disorder and short-range order in structure. Its unique structural characteristics endow it with excellent catalytic activity, selectivity, anti-poisoning and corrosion resistance, and it is also environmentally friendly. [0003] Because the amorphous alloy catalyst prepared by the traditional quenching method has the following disadvantages: (1) the requirements for the reaction device are relatively high, and the investment is large; (2) the synthesized catalyst is not active and must be activated before use; (3) ) Since the a...

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Problems solved by technology

[0003] Because the amorphous alloy catalyst prepared by the traditional quenching method has the following disadvantages: (1) the requirements for the reaction device are relatively high, and the investment is large; (2) the synthesized catalyst is not active and must be activated before use; (3) ) Since the amorphous structure is a thermodynamic metastable state, a crystallization reaction will occur when heated, and the thermal stability is poor; (4) The specific surface area of ​​the catalyst is small, generally 0.1-1m 2 / g

However, this method has the following problems: (1) the reduction reaction is rapid and violently exothermic, causing local overheating, resulting in agglomeration and / or crystallization of the generated alloy particles; (2) the process of dropping the reducing agent has a problem of excessive local concentration , making this process an unbalanced process

Even if a very high stirring speed is used, the particle size of the prepared amorphous alloy catalyst is still very uneven, and the particle size distribution range is very wide, resulting in large differences in catalytic performance, poor thermal stability and possible increase in pressure drop in fixed bed reactions. (3) Rapid nucleation and rapid growth cause the prepared particles to wrap a large number of unreduced metal oxides and decomposed boron oxide species. These impurities, which are difficult to completely remove by physical and chemical methods, cover part of the active sites and cause catalytic activity. decline

The above factors have become the bottleneck for the industrial application of amorphous alloy catalysts

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