Ru-Pd/C Catalyst for Neutral pH Chlorate Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts for reducing chlorate (ClO3−) in water purification are ineffective at neutral or alkaline pH, requiring acidic conditions and high doses of platinum group metals (PGMs) to maintain activity, which is not feasible in many water treatment scenarios.
Innovation Solution
Development of Ru0 catalysts, in combination with Pd0, Pt0, Rh0, or Ir0, supported on a solid material, which enables high activity for ClO3− reduction at pH 7 through a rapid and convenient preparation method, showcasing synergy and robustness in challenging scenarios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional PGM catalysts are used for ClO3− reduction, then catalytic activity is maintained under acidic conditions, but the catalysts become ineffective at neutral or alkaline pH
Solution Approach 1:
The patent modifies the catalyst composition by combining Ru with other PGMs (Pd, Pt, Rh, or Ir) to change the catalytic parameters, enabling effective operation across a broader pH range including neutral conditions where conventional catalysts fail
Solution Approach 2:
The invention creates composite catalyst materials by combining Ru with another PGM component, where the synergistic interaction between the two metals enhances both activity and adaptability to different pH conditions, resolving the contradiction between maintaining reliability across varying pH environments
2Productivity
If acidification is applied to maintain catalyst activity, then ClO3− reduction efficiency is improved, but the complexity and cost of the water treatment process increases
Solution Approach 1:
The patent extracts the pH dependency limitation from the catalytic system by designing a Ru-based catalyst that inherently functions at neutral pH without requiring external acidification, thereby eliminating the need for additional pH adjustment equipment and processes
Solution Approach 2:
The catalyst is designed to autonomously function at neutral pH conditions without requiring external intervention for pH adjustment, making the system self-sufficient and eliminating complex acidification infrastructure
3Productivity
If high doses of PGM catalyst are used to compensate for activity loss at neutral pH, then ClO3− reduction efficiency is maintained, but the cost and quantity of precious metals increases
Solution Approach 1:
The patent changes the catalytic parameters by selecting Ru as the base metal combined with another PGM, creating a system that achieves high productivity at neutral pH with optimized metal dosage, avoiding the need for excessive PGM quantities
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 Ru—Pd/C catalyst achieves unprecedented high activity for ClO3− reduction at neutral pH, with over 50% reduction efficiency, outperforming existing catalysts and maintaining performance in the presence of inhibitory species, demonstrating robustness and efficiency in water treatment applications.
Implementation Method 1
Ru0 catalysts, in combination with Pd0, Pt0, Rh0, or Ir0, supported on a solid material, which enables high activity for ClO3− reduction at pH 7
Implementation Method 2
Platinum group metal (PGM) catalyzed hydrogenation provides a clean degradation route: ClO3−+3H2→Cl−+3H2O
Data Source
AI summary
The invention provides a catalyst comprising 1) Ru0 and 2) Pd0, Pt0, Rh0, or Ir0, on a solid support. The catalyst is useful for water purification applications. In particular, the catalyst is useful for reducing ClO3− and ClO2− from water. The invention also provides catalysts that are useful for reducing nitrate in a water supply and methods for their use.