Tin-Based Catalyst for Lean Burn Engine Emissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing catalysts for lean burn engines require high amounts of precious metals like platinum and palladium, leading to increased costs and strain on metal supplies, as they struggle to efficiently reduce nitrogen oxides, carbon monoxide, and hydrocarbons in exhaust gases while adhering to stringent environmental regulations.
Innovation Solution
Development of catalyst formulations using binary and ternary compositions of tin (Sn) compounds with titanium (Ti) and zirconium (Zr), which include low amounts of precious metals or no precious metals at all, utilizing base metals like copper, iron, and nickel, and high surface area inorganic oxides to convert CO and hydrocarbons into harmless products, reducing the reliance on expensive platinum group metals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high amounts of platinum or palladium are used in oxidation catalysts, then emission control efficiency is improved, but cost and precious metal consumption increase significantly
Solution Approach 1:
The invention changes the chemical composition parameters of the catalyst by using base metals (Cu, Fe, Ni, Mn, Co, Zn) instead of precious metals, and by employing specific oxide combinations (CuO-Al2O3, Fe2O3-Al2O3, NiO-Al2O3, etc.) with controlled weight ratios to achieve effective CO oxidation at lower temperatures without requiring platinum or palladium
Solution Approach 2:
The invention replaces expensive precious metals with inexpensive base metals that are abundant and economical, using formulations such as CuO-Al2O3, Fe2O3-Al2O3, and NiO-Al2O3 that provide effective catalysis at low cost, making the catalyst economically viable for widespread emission control applications
2Quantity of substance
If base metals are used instead of precious metals, then cost is reduced, but catalytic activity at low temperatures may be insufficient
Solution Approach 1:
The invention creates composite catalyst materials by combining base metal oxides (CuO, Fe2O3, NiO, MnO, CoO, ZnO) with aluminum oxide (Al2O3) in specific weight ratios, forming composite structures that enhance the low-temperature catalytic activity of the base metals while maintaining cost-effectiveness, with formulations like CuO-Al2O3, Fe2O3-Al2O3, and NiO-Al2O3 demonstrating superior low-temperature CO oxidation performance
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
These catalysts achieve effective CO conversion at lower temperatures with reduced precious metal content, lowering costs and extending metal supplies, while maintaining high emission control efficiency, making them suitable for lean burn engines, gas turbines, boilers, and furnaces.
Implementation Method 1
a catalyst for the conversion of CO and/or hydrocarbons in an exhaust stream including a Sn compound
Implementation Method 2
These catalysts achieve effective CO conversion at lower temperatures with reduced precious metal content
Data Source
AI summary
Embodiments of the present disclosure include a catalyst for the conversion of CO and/or hydrocarbons in an exhaust stream including a Sn compound selected from the group consisting of a binary composition comprising Sn and Ti, a ternary composition comprising Sn, Ti and Zr, and mixtures of any thereof. In those embodiments, the binary composition may include Sn(X)Ti(y)O2, wherein x+y=1, 0.85>y>0. In other embodiments of the present disclosure, the Sn compound includes a ternary composition including Sn(a)Ti(b)Zr(c)O2, wherein a is 0.25, b is 0.25 and c is 0.5. Certain embodiments of this disclosure include a method for the conversion of CO in an exhaust stream, including contacting an exhaust stream containing CO with the catalyst described above containing a Sn compound. In other embodiments, the exhaust stream includes hydrocarbons.