CN-122010193-A - Preparation method of cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid and application of prepared catalyst

CN122010193ACN 122010193 ACN122010193 ACN 122010193ACN-122010193-A

Abstract

The invention provides a preparation method of a cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid and application of the prepared catalyst. Firstly, nickel ethylenediamine tetraacetate in the waste nickel plating liquid is broken by sodium hypochlorite oxidation, nickel hydroxide precursor is deposited by nickel hydroxide induction, then cobalt auxiliary components are loaded on nickel hydroxide by cobalt nitrate through an impregnation method, and the cobalt modified nickel hydroxide catalyst based on the nickel plating waste liquid is obtained after purification. When the catalyst is used for preparing ammonia by electrochemical nitrate reduction, cobalt and a nickel hydroxide matrix in the catalyst generate strong interaction, the adsorption and conversion paths of active hydrogen and nitrogen-containing species on the catalytic surface are effectively optimized, excellent electrocatalytic performance is shown, the Faraday efficiency reaches 98.38% under-0.47V (vs. RHE), and the yield reaches 10.06 mg NH3 h ‑1 mg cat. ‑1 under-0.67V (vs. RHE).

Inventors

CAI YUEPENG
Han Aoyan
ZHANG YUN
Wu Zitian
Zheng shida
SONG CHUNLEI

Assignees

华南师范大学

Dates

Publication Date: 20260512
Application Date: 20260213

Claims (10)

1. The preparation method of the cobalt modified nickel hydroxide catalyst based on the nickel plating waste liquid is characterized by comprising the following steps: S1, adding sodium hypochlorite into nickel plating waste liquid containing nickel complex, heating to perform oxidation and network breaking treatment, simultaneously adding nickel hydroxide as a precipitation inducer, adjusting the pH of the solution, and purifying to obtain nickel hydroxide precursor; S2, adding the nickel hydroxide precursor into water, performing ultrasonic dispersion, adding a cobalt nitrate solution, heating, stirring and impregnating, adjusting the pH value of the solution, continuing impregnating, and purifying to obtain a cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid; Wherein, the The concentration of cobalt in the cobalt nitrate solution is 0.5-1.5 g.L -1 ; The mass ratio of cobalt in the nickel hydroxide precursor and the cobalt nitrate solution is 100:5-15.
2. The method for preparing a cobalt-modified nickel hydroxide catalyst based on a nickel plating waste liquid according to claim 1, wherein in step S1, the heating temperature is 25 to 35 ℃.
3. The method for preparing a cobalt-modified nickel hydroxide catalyst based on a nickel plating waste liquid according to claim 1, wherein in step S1, the pH of the solution ranges from 10 to 12.
4. The method for preparing a cobalt-modified nickel hydroxide catalyst based on a nickel plating waste liquid according to claim 1, wherein in step S2, the heating temperature is 50 to 70 ℃.
5. The method for preparing a cobalt-modified nickel hydroxide catalyst according to claim 1, wherein in step S2, the pH of the solution is in the range of 9 to 10.
6. A cobalt-modified nickel hydroxide catalyst based on a nickel plating waste liquid, characterized by being produced by the method for producing a cobalt-modified nickel hydroxide catalyst based on a nickel plating waste liquid according to any one of claims 1 to 5.
7. Use of the cobalt-modified nickel hydroxide catalyst based on nickel plating waste liquid according to claim 6 in the electrochemical nitrate reduction for preparing ammonia.
8. The use of the cobalt-modified nickel hydroxide catalyst based on nickel plating waste liquid according to claim 7 in the electrochemical nitrate reduction ammonia production, wherein the cobalt-modified nickel hydroxide catalyst based on nickel plating waste liquid is loaded on a conductive hydrophilic carbon paper substrate as a working electrode, and the electrocatalytic nitrate reduction ammonia production reaction is carried out in an alkaline electrolyte containing nitrate ions.
9. The use of a cobalt modified nickel hydroxide catalyst based on nickel plating waste solution according to claim 8 for electrochemical nitrate reduction to ammonia, wherein the electrocatalytic reduction reaction has a potential of-0.27V to-0.67V (vs. RHE).
10. The application of the cobalt-modified nickel hydroxide catalyst based on the nickel plating waste liquid in preparing ammonia by electrochemical nitrate reduction according to claim 8, wherein the alkaline electrolyte is a mixed solution of KNO 3 and KOH, wherein the concentration of KNO 3 in the alkaline electrolyte is 0.05-0.2M, and the concentration of KOH is 1-3M.

Description

Preparation method of cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid and application of prepared catalyst Technical Field The invention relates to the technical fields of environmental chemical engineering and electrocatalysis, in particular to a preparation method of a cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid and application of the prepared catalyst. Background Ammonia is an important chemical raw material and is widely applied to a plurality of industries such as agricultural fertilizers, chemical industry, refrigeration, energy sources and the like. Traditional ammonia production relies mainly on the haber-bosch process, which is energy-intensive and has a significant environmental impact, especially carbon emissions problems under high temperature and pressure conditions. Thus, developing alternative, sustainable ammonia production processes is a key challenge for the global chemical industry. Electrochemical nitrate reduction synthesis of ammonia (NO 3 RR) has received attention as a promising ammonia synthesis method. The technology can not only reduce the content of harmful nitrate in the environment (especially surface water), but also recover valuable nitrogen resources, upgrade and convert the valuable nitrogen resources into high-value chemicals, and provide a sustainable application path for nitrate recovery and utilization. The reduction of nitrate to ammonia is a complex electrochemical process with multi-electron (8 electrons)/multi-proton (9 protons) coupling, which is slow in kinetics, thus a catalyst is often used to regulate the reaction. The NO 3 RR synthesis ammonia is generally divided into two stages, nitrate reduction to the stable intermediate nitrite, and subsequent nitrite hydrogenation to NH 3. To achieve high ammonia yields, the reaction interface is often required to possess sufficient active hydrogen for coupling nitrate/nitrite reduction to produce ammonia, and to prevent the active hydrogen from autotransformed to hydrogen. In combination with the requirement that active hydrogen comes from water cracking under alkaline condition, the NO 3 RR ammonia catalyst must be reasonably designed and constructed by combining various factors. Nickel-based materials, particularly nickel hydroxide, have good electrochemical activity and stability under alkaline conditions, can effectively promote the cracking of water, generate rich hydrogen species on the surface of the catalyst, have certain adsorption/activation capability on nitrate and intermediate species, and are considered as NO 3 RR ammonia production catalysts with great potential. However, the catalytic activity and selectivity of pure nickel hydroxide are generally difficult to meet the practical application requirements. The cobalt element is proved to be an effective auxiliary component for improving the reduction performance of nitrogen-containing species, and the adsorption strength of the catalyst surface to active hydrogen, nitrate and intermediate species is hopefully optimized through cobalt introduction, and the conversion and coupling paths of each species are regulated, so that the ammonia production yield of NO 3 RR is obviously improved. In addition, the high-value nickel-based catalyst prepared by taking the nickel electroplating waste liquid as a nickel source belongs to the environment field waste green recycling category as does NO 3 RR high-value ammonia, and completely accords with the national double-carbon strategic target. In view of the foregoing, a new solution is needed to solve the problems of the prior art. Disclosure of Invention Based on the above, the invention provides a preparation method of a cobalt modified nickel hydroxide catalyst based on nickel plating waste liquid and application of the prepared catalyst. Firstly, nickel ethylenediamine tetraacetate in the waste nickel plating liquid is broken by sodium hypochlorite oxidation, a nickel hydroxide precursor with high activity is deposited by using nickel hydroxide induction, then cobalt auxiliary components are loaded on nickel hydroxide by using a dipping method through cobalt nitrate, and the cobalt modified nickel hydroxide catalyst based on the nickel plating waste liquid is obtained after purification. When the catalyst is used for preparing ammonia by electrochemical nitrate reduction, cobalt in the catalyst and a nickel hydroxide matrix generate strong interaction, and the adsorption and conversion paths of active hydrogen and nitrogen-containing species on the catalytic surface are effectively optimized, so that the catalyst has excellent electrocatalytic performance for preparing ammonia by nitrate reduction, the Faraday efficiency reaches 98.38% under-0.47V (vs. RHE), and the yield reaches 10.06 mg NH3 h-1 mgcat.-1 under-0.67V (vs. RHE). The invention develops the cobalt-modified nickel hydroxide composite material by taking the nickel plating waste liquid as a