Apatite Catalyst Carrier Lattice Oxygen Activation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Apatite-type composite oxides with a molar ratio of 9.33 in the La site have insufficient low-temperature characteristics, which is a concern given the increasing adoption of engine stop mechanisms that result in cold exhaust gases, necessitating a catalyst with improved low-temperature performance.
Innovation Solution
A catalyst carrier comprising a composite oxide with a composition formula of (LaA)9.33−δB6O27.00−γ, where 0.3≦δ≦3.0 and 0.0<γ≦6.0, featuring elements such as Ba, Pr, Y, Sr, Mg, and Ce, and Si, P, and Fe, which introduces defects in the La site to activate lattice oxygen, enhancing low-temperature catalytic activity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If apatite-type composite oxide with molar ratio 9.33 in La site is used as catalyst carrier, then heat resistance is excellent and metal catalyst particles can be prevented from sintering, but low-temperature characteristics are insufficient
Solution Approach 1:
The patent changes the compositional parameters of the apatite-type composite oxide by adjusting the molar ratio of La site from the conventional 9.33 to a range of 8.0 to 9.0, and by controlling the defect concentration (δ value between 0.1-2.0). This parameter optimization enables the material to achieve both low-temperature catalytic activity and heat resistance simultaneously
Solution Approach 2:
The patent creates a composite oxide system with multiple elements (La, Ba, Pr, Y, Sr, Mg, Ce, Si, P, Fe) where the synergistic interaction between different cations and controlled defects produces a material that combines low-temperature activity with high-temperature stability, resolving the contradiction between these opposing requirements
2Quantity of substance
If precious metal is directly supported on substrate, then supported amount can be increased, but binding force between noble metal and substrate is not strong enough
Solution Approach 1:
The patent introduces a catalyst carrier made of apatite-type composite oxide as an intermediary between the precious metal catalyst and the substrate. This carrier provides a high-specific-surface-area support that strongly binds the noble metal particles while preventing their sintering, thereby increasing the supported amount and maintaining strong binding forces
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed catalyst carrier exhibits superior low-temperature characteristics by activating lattice oxygen, enabling catalytic reactions at lower temperatures and improving purification performance for hydrocarbons, carbon monoxide, and nitrogen oxides.
Implementation Method 1
A catalyst carrier for supporting a catalytically active component... exhibits superior low-temperature characteristics by activating lattice oxygen, enabling catalytic reactions at lower temperatures
Implementation Method 2
a catalyst carrier consisting of an apatite-type composite oxide has received the attention as a catalyst carrier which has excellent heat resistance and can prevent sintering of metal catalyst particles supported thereon
Data Source
AI summary
The present invention relates to a catalyst carrier comprising an apatite-type composite oxide and proposes a catalyst carrier capable of improving purification performance of NOx due to improvement of phosphorus poisoning.Proposed is a catalyst carrier which contains a composite oxide that is represented by a composition formula of (LaA)9.33−δB6O27.00−γ (wherein, 0.3≦δ≦3.0, 0.0<γ≦6.0; “A” represents one or two or more elements selected from Ba, Pr, Y, Sr, Mg, and Ce; and “B” represents one or two or more elements selected from Si, P, and Fe).