Cu-Containing Zeolite Slurry for Direct Catalyst Synthesis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of Cu-containing zeolite catalysts is complex and costly due to multiple treatment steps, which can reduce the crystallinity of zeolites and impair high-temperature performance.
Innovation Solution
A slurry composition comprising aluminosilicate, Cu, and water with specific molar ratios, along with a binder, is used to simplify the catalyst production process by omitting calcination and ion-exchange treatments, allowing for the direct formation of a Cu-containing zeolite with a CHA-type crystal structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If multiple treatment steps (calcination, ion-exchange) are performed to produce Cu-containing zeolite catalysts, then the catalyst can be formed, but the zeolite crystallinity is reduced and high-temperature performance is impaired
Solution Approach 1:
The patent combines multiple treatment steps (calcination and ion-exchange) into a single hydrothermal treatment step. The slurry composition contains both Cu source and zeolite precursor materials, allowing simultaneous formation of Cu-containing zeolite with high crystallinity through one-step hydrothermal synthesis, eliminating the need for sequential calcination and ion-exchange treatments that previously degraded crystallinity.
Solution Approach 2:
The patent changes the chemical parameters of the treatment process by using hydrothermal treatment conditions (temperature, pressure, pH, and composition of slurry) that enable direct formation of Cu-containing zeolite. By controlling parameters such as SiO2/Al2O3 ratio, Cu/Al ratio, and hydrothermal treatment temperature (80-200°C), the process achieves high crystallinity catalyst formation without harsh calcination that would otherwise be required.
2Ease of manufacture
If multiple treatment steps are used to produce the catalyst, then the catalyst can be formed, but the production cost increases
Solution Approach 1:
The patent merges multiple expensive treatment steps (calcination requiring high energy input, ion-exchange requiring multiple washing and drying cycles) into a single hydrothermal treatment step. This consolidation reduces energy consumption, minimizes water and chemical usage, and shortens processing time, thereby significantly reducing production costs while maintaining catalyst quality.
Solution Approach 2:
The slurry composition is designed to be self-assembling under hydrothermal conditions, where the Cu source and zeolite precursor automatically form the desired Cu-containing zeolite structure without requiring additional treatment steps. This self-organization during hydrothermal treatment eliminates the need for costly post-processing operations.
3Object-generated harmful factors
If calcination treatment is performed to remove organic structure directing agent, then the agent is removed, but the zeolite crystallinity is reduced
Solution Approach 1:
The patent changes the removal method by using mild hydrothermal treatment conditions (80-200°C, aqueous environment) instead of high-temperature calcination. The organic structure directing agent is gradually removed or transformed under these gentle conditions, preserving the zeolite crystallinity while achieving the necessary removal of organic contaminants.
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
This method reduces catalyst production costs, maintains zeolite crystallinity, and enhances high-temperature performance, enabling efficient NOx purification even in severe environments.
Implementation Method 1
The CHA-type zeolites are generally produced by hydrothermal reaction using starting materials such as a Si element source, an Al element source, and an alkali source
Implementation Method 2
the selective catalytic reduction (SCR) of NOx using a nitrogen compound such as ammonia or urea is used as the NOx purification system
Data Source
AI summary
A slurry composition for a catalyst and a method for producing the same, a catalyst and a method for producing the same using the slurry composition for a catalyst. The method omits many heretofore required treatment steps and reduces catalyst production cost. The method comprising the steps of providing a slurry composition for a catalyst, comprising at least an aluminosilicate, Cu, and water, and having a solid concentration of 0.1% by mass to 90% by mass, wherein a component for a catalyst has composition represented by Al2O3·xSiO2·yT2O·zCuO (wherein T is a quaternary ammonium cation, and x, y and z are numbers that satisfy 10≤x≤40, 0.1≤y<2.0, and 0.1≤z<2.0, respectively) in terms of molar ratio based on an oxide; coating at least one side of a support with this slurry composition; and heat-treating at 350° C. or higher.