JPS61119606A - Production of amorphous metallic powder - Google Patents

Abstract

PURPOSE:To obtain amorphous Ni-P powder having a small grain size and large surface area by bringing an aq. soln. incorporated therein with an Ni salt, hypophosphite, complexing agent, phosphite, phosphorous precipitation accelerator, etc. into Ni-ion reduction reaction at a high temp. CONSTITUTION:The Ni salt such as nickel chloride or nickel sulfate, hypophosphite as the reducing agent, the complexing agent, the phosphite as the reaction initiator and the N-(2hydroxy ethyl) ethylenediamine-N',N'-triacetic trialkali metallic salt (C10H15N2Na3O7) are compounded. Further >=1 kinds among ammonium sulfate, lithium sulfate, potassium sulfate, sodium sulfate, etc. are incorporated therein to prepare an aq. soln. for reaction. The pH of the aq. soln. is adjusted to about 7 and the water temp. is increased to 70-100 deg.C to progress the nickel-ion reduction reaction so that amorphous Ni-P powder is precipitated. The precipitate is lightly ground and the pulverous powder of the amorphous metal suitable for a catalyst, etc. is obtd.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention relates to a method for producing a catalyst used in the hydrogen reaction of -carbon oxide (Co) and -nitrogen oxide (No), Nickel (N i ) has a fast reaction rate and a large surface area.
-R(P)- It is used as an amorphous catalyst.

(Prior Art) As a conventional method for producing N1-P amorphous catalyst, there is a liquid quenching method, which is described in the Journal of Chemical Engineering (VOL 47.
P41.1983) It is disclosed that a ribbon with a thickness of 18 μm having a composition of 2N1soPzo is manufactured by a rapid cooling method, and the specific surface area (BET, Nz) is 0.2rrr/g, and furthermore, a method for manufacturing an amorphous powder is described. There are manufacturing methods that reduce the size of droplets in a gas using the spray method, atomization method, and cavitation method.

(Problems to be Solved by the Invention) However, in the ribbon quenching method, in order to provide continuity to the ribbon, there is a natural limit to the thickness, and it is difficult to dramatically increase the surface area. Even in the manufacturing method, it is difficult to manufacture fine powder. For example, the ultrasonic atomization method can produce particles with a particle size of 12.5 to 6.5 μm.
Particle sizes smaller than this are difficult.

Therefore, the technical object of the present invention is to increase the surface area per weight by reducing the particle size of amorphous powder as much as possible.

[Structure of the invention]

(Means for solving the problem) The method taken to solve the above technical problem was to chemically reduce metal ions in an aqueous solution to produce ultrasmall particles. Nickel salt such as nickel, hypophosphite as a reducing agent, phosphite as a complexing agent 1 reaction initiator.

As a phosphorus precipitation accelerator, N-(2hydroxyethyl)-ethylenediamine-N,N',N'-triacetic acid trial-alkali metal salt (hereinafter referred to as C1°H+5NiNa30) and ammonium sulfate, lithium sulfate, potassium sulfate, and sodium sulfate were used. An aqueous solution consisting of one or more components selected from sulfates is heated to a high temperature of 80 to 100°C to perform a nickel ion reduction reaction to precipitate and produce amorphous N1-P powder.

In addition, N1ao exhibits high activity in hydrogenation reactions of Co and No.
The high phosphorus content called Pro is also described in the above chemical engineering, and a P content of 15 to 20 at% is secured by adding C3°H15Nt Na 307 and the above sulfate to the reaction solution from which amorphous powder is precipitated. This is what I did.

(Operation) The technical means is as follows. That is, the aqueous solutions are A liquid and B liquid, and A liquid contains CIo H+ s N zN
a, 0. and the above-mentioned sulfate were added.

A liquid N i Cj' z →30 g /
II binding acid Na -50g/ILi,
SO4 → 25 g/I CIoHrsNz Na3- 07 /1 Saccharin N
a -1g/j2 B tM N i Cl z -30g
/ 1 acidic acid Na -50g / 1 saccharin Na → 1g/l The table shows samples 1 to 1. Kokitsui-co Ae7i,
” Shows the precipitation status of asbestos powder. For Sho 1 to Sho 3, the minimum particle size is small and Pat+m% is 16.0 or more.
Although there are some measurement errors, the overall evaluation is judged to be good.

Furthermore, from the chemical engineering literature mentioned above, P shown in N1aop2o
It is stated that #20 shows the most activation, and as an overall evaluation in Table 2, ■ fineness of particle size as seen in the photograph and ■ P component close to 20 is 16.
An evaluation was performed on a 5 atm% product.

(Example) Hereinafter, specific examples according to the present invention will be described.

Example-1 Nickel chloride 30 g/IA
Bath type Sodium hypophosphite 30g/β sample patient 3 Sodium phosphite 40g/βC10H15Nz N
az o? 3 g/l lithium sulfate 2
5g/n Sodium saccharin l g/l Sodium saccharin 50g/7! The aqueous solution consisting of was adjusted to pH-7, the bath temperature was raised to 90°C or higher, and the reaction was carried out to obtain amorphous N1-P powder.

As a result of measuring the N1-P composition and particle size of the powder using EPMA and a microscope, the P content 9 particle size was P atomic % 17
．． The average particle size was 2 at% and 1 μm.

Next, 1 of the amorphous particle size of NQ1-7 in Table 1 above.
Fig. 1 shows the situation in a micrograph taken at a magnification of 1,000 times.

〔Effect of the invention〕

The present invention has the following unique effects. In other words, in order to increase the specific surface area of the catalyst produced by the conventional liquid quenching method, it is possible to finely pulverize the ribbon produced by the roll method or the powder produced by the atomization method; , crushing high-strength amorphous materials has poor pulverizing effect and requires a large amount of energy and a long time.
Furthermore, it is difficult to make the particle size uniform, resulting in poor yield. However, in the production method of the present invention, the particle size can be made uniform by keeping the residence time of the fine powder in the reaction solution constant, and even if the residence time in the reaction solution is long, the precipitation form of the particles can be made uniform. The particles precipitate in the form of clusters of small particles gathered together like a bunch of grapes, and increase in size. Small particles can be produced.

Next, there is a method of lowering the PH as a means of increasing the P content of N1-P amorphous, but lowering the PH lowers the precipitation speed of the powder, but the present invention does not allow phosphorus precipitation as described in 1); By adding a promoter, a high P content can be ensured without reducing the reaction speed.

[Brief explanation of drawings]

The figures are micrographs taken at a magnification of 1000 times, in which (1) to (5) are those of the present embodiment, and (6) to (7) are those of the conventional example.

Claims (1)

[Claims] (1) Nickel salts such as nickel chloride and nickel sulfate,
(2) hypophosphite as a reducing agent, (3) a complexing agent, (
4) Phosphite as a reaction initiator, (5) N-(2hydroxyethyl)-ethylenediamine-N,N',N'-triacetic acid trial-alkali metal salt (C_1_0H_1_5N_2Na_3O_7) and ammonium sulfate as phosphorus precipitation accelerators , lithium sulfate, potassium sulfate, sodium sulfate, or one or more components selected from the group consisting of sulfates of lithium sulfate, potassium sulfate, and sodium sulfate.
A method for producing amorphous metal powder by precipitating P powder.