CN-122006727-A - Water treatment ozone catalyst and preparation method and application thereof

CN122006727ACN 122006727 ACN122006727 ACN 122006727ACN-122006727-A

Abstract

The invention provides a water treatment ozone catalyst, a preparation method and application thereof. The water treatment ozone catalyst comprises a carbon-based carrier and active metal oxide particles M x N y O z‑δ distributed on the surface of the carbon-based carrier, wherein M and N are respectively selected from at least one of transition metal or lanthanide metal, x and y are positive numbers, x and y= (1-9) are satisfied, 1 is 0< delta < z, the active metal oxide particles M x N y O z‑δ are partially embedded in the carbon-based carrier and partially embedded in the carbon-based carrier, and the problems of poor agglomeration and dispersion, insufficient activity and poor structural stability of metal particles of metal oxides used in the current HCO system are solved. The invention also provides a water treatment ozone catalyst, a preparation method and application thereof.

Inventors

SHI KAIMIN
LIANG ZHU
LIN LIN
LI XIAOYAN
WANG PEI
ZHAO QI
WANG YIXUAN

Assignees

香港大学
清华大学深圳国际研究生院

Dates

Publication Date: 20260512
Application Date: 20251231

Claims (10)

1. The water treatment ozone catalyst is characterized by comprising a carbon-based carrier and active metal oxide particles M x N y O z-δ distributed on the surface of the carbon-based carrier, wherein M and N are respectively selected from at least one of transition metals or lanthanide metals, x and y are positive numbers, and x is y= (1-9) 1,0< delta < z, and the active metal oxide particles M x N y O z-δ are partially embedded in the carbon-based carrier and partially embedded in the carbon-based carrier.
2. The water treatment ozone catalyst of claim 1, wherein the transition metal comprises at least one of Fe, mn, co, ni and Cu, and/or the lanthanide metal comprises at least one of Ce and La.
3. The water treatment ozone catalyst according to claim 1, wherein the metal combination in the active metal oxide particles M x N y O z-δ comprises Co-Ce, mn-Ce, fe-Ce, co-Mn or Fe-Mn, and/or the metal combination in the active metal oxide particles M x N y O z-δ comprises a mixed oxide or solid solution of Co-Mn-Ce, fe-Co-Ce.
4. A method for preparing the water treatment ozone catalyst as claimed in any one of claims 1 to 3, comprising the steps of precursor generation, carbon layer construction and oxygen vacancy induction, or the steps of precursor generation and carbon layer construction being performed simultaneously and then oxygen vacancy induction, which are sequentially performed.
5. The method according to claim 4, comprising the steps of: S1, coprecipitation nucleation and uniform dispersion, namely dissolving soluble metal salt corresponding to active metal oxide particles M x N y O z-δ in water according to a molar ratio x and y, adding the soluble metal salt into a precipitator, reacting, generating in situ an M-N metal hydroxide/basic salt precursor which is uniformly dispersed, and carrying out solid-liquid separation after reaching a titration end point to obtain a precursor; S2, calcining the precursor in air to form a stable active phase, namely calcining the precursor in air atmosphere to finish dehydration and oxidation to obtain an M-N mixed oxide; S3, carrying out hydrothermal carbon compounding and cladding, namely mixing the M-N mixed oxide obtained in the step S2 with a reducing carbon source, and carrying out hydrothermal reaction to generate carbon spheres, wherein the carbon spheres and the M-N mixed oxide form a composite structure; And S4, drying and carrying out thermal stabilization on the product in the step S3 under an inert atmosphere to finish densification of a carbon phase and construction of oxygen vacancies, thereby obtaining the water treatment ozone catalyst.
6. The method according to claim 5, wherein in step S1, the soluble metal salt corresponding to the active metal oxide particles M x N y O z-δ is dissolved in water according to a molar ratio x:y, and then added dropwise into a precipitating agent, and the solution is stirred at 25-70 ℃ until the titration end point is pH=9.0-11.5, and aged for 0.5-6 hours, and/or in step S1, the precipitating agent comprises at least one of sodium hydroxide, sodium carbonate, sodium bicarbonate or ammonia water.
7. The method according to claim 5, wherein in step S2, the calcination temperature is 250-750 ℃, and/or in step S2, the calcination time is 1-6 hours.
8. The method according to claim 5, wherein in the step S3, the temperature of the hydrothermal reaction is 140-220 ℃, and/or the time of the hydrothermal reaction in the step S3 is 2-24 hours.
9. A method for degrading organic micropollutants in water, comprising the steps of: a water treatment ozone catalyst according to any one of claims 1 to 3 is added to the wastewater to be treated, and catalytic ozone oxidation reaction is carried out under the condition of ozone introduction.
10. The method according to claim 9, wherein the concentration of the organic micro-pollutants is 10-100mg/L, and/or the adding amount of the water treatment ozone catalyst is 0.1-1g/L, and/or the ozone concentration is 20-40mg/L.

Description

Water treatment ozone catalyst and preparation method and application thereof Technical Field The invention belongs to the technical field of water treatment, and particularly relates to a water treatment ozone catalyst, a preparation method and application thereof. Background With the acceleration of the progress of new industrialization and high quality urbanization, the problem of accumulation of refractory organic pollutants and new pollutants (such as dyes, pesticides, antibiotics, hormone compounds, etc.) in water is increasingly prominent, and has become a significant challenge in the field of global water environment management. The pollutants have the characteristics of stable chemical structure, poor biodegradability, strong potential toxicity and the like, can be remained in a water ecological system for a long time and form an accumulation effect, not only destroy the ecological balance of the water body, but also form serious threat to human health. Traditional water treatment technologies such as physical adsorption, membrane separation, chemical coagulation precipitation, biological activated sludge process and the like have obvious limitations in treating the pollutants, are generally characterized by low treatment efficiency, high running cost and long reaction period, are easy to produce toxic and harmful intermediate byproducts, and are difficult to realize deep mineralization removal of the pollutants. Advanced oxidation techniques (AOPs) can generate highly active radicals (especially, OH with oxidation-reduction potential as high as +2.80V) in a non-selective manner, so that the organic chemical structure can be thoroughly destroyed, and the advanced oxidation techniques (AOPs) are a research hot spot in the field of water treatment in recent years. The ozone oxidation technology has been widely used in the fields of drinking water purification, sewage deep treatment, reclaimed water recycling and the like by virtue of the advantages of strong oxidizing property, no need of additional reagent, green and environment-friendly product and the like. However, the ozone treatment alone still faces a plurality of technical bottlenecks that the ozone utilization rate is generally lower than 50%, the Total Organic Carbon (TOC) removal rate is generally lower than 25%, the reaction selectivity is high, toxic byproducts can be generated in part of the reaction process, and the application efficiency of the ozone treatment in the treatment of refractory organic wastewater is severely restricted. To overcome the technical drawbacks of ozone oxidation alone, heterogeneous catalytic ozone oxidation technology (Heterogeneous Catalytic Ozonation, HCO) has evolved. The technology promotes ozonolysis and continuously generates a plurality of active oxygen species such as OH, O 2-、1O2 and the like by introducing a solid catalyst, not only improves the reaction rate and mineralization capacity, but also avoids the problem of secondary pollution of metal ions in homogeneous catalysis, and has wide application prospect in complex wastewater treatment. At present, the common metal oxide catalyst in the HCO system generally has the problems of poor agglomeration and dispersion of metal particles, insufficient catalytic activity, poor structural stability and the like, so that the catalytic efficiency is difficult to further improve. Therefore, how to construct a catalytic system with high dispersibility, high activity and high stability through the design of catalyst materials and interface regulation and control solves the key technical problems of low ozone utilization rate, weak mineralization capacity, poor anti-interference performance and the like, and becomes a core requirement for promoting the engineering application of heterogeneous catalytic ozone oxidation technology. Disclosure of Invention The metal oxide and hydroxide are generally considered as catalysts for effectively promoting ozonolysis, however, the metal oxide used in the HCO system generally faces the problems of poor agglomeration and dispersion, insufficient activity, poor structural stability and the like of metal particles, and severely restricts the catalytic efficiency. Therefore, there is a need to develop system optimization and innovation from multiple dimensions of catalyst material design, interface regulation, etc. The present invention aims to solve at least one of the above technical problems in the prior art. Therefore, the invention provides a water treatment ozone catalyst, which solves the problems of poor agglomeration and dispersion, insufficient activity and poor structural stability of metal particles existing in metal oxides used in the existing HCO system. The first aspect of the invention provides a water treatment ozone catalyst, which comprises a carbon-based carrier and active metal oxide particles M xNyOz-δ distributed on the surface of the carbon-based carrier, wherein M and N are respectively selected from