Composite Oxygen Transport Membrane for Low-Temperature Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing oxygen transport membranes face challenges in maintaining thickness at low temperatures while enhancing oxygen transport capacity, as they suffer from reduced catalytic ability and internal fractures, leading to decreased efficiency and product yield.
Innovation Solution
A composite material type oxygen transport membrane is developed, comprising a conductive oxygen ion conducting substrate with a high ionic conductivity and a reductive oxygen ion conducting layer of high catalytic capacity, where small particles of mixed conductor materials are uniformly dispersed and adhered to the substrate, formed through a method involving tape casting, sintering, and deposition processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the thickness of the oxygen transport membrane is reduced to enhance oxygen transport efficiency, then the oxygen ion moving distance is reduced and transport efficiency is improved, but the overall strength of the membrane becomes inadequate and damage occurs during assembly or heating
Solution Approach 1:
The patent uses a composite structure consisting of a porous support substrate and a dense ceramic layer. The porous substrate provides mechanical strength while the dense ceramic layer enables oxygen ion transport. This composite approach allows the membrane to maintain both sufficient strength and high oxygen transport efficiency by combining materials with complementary properties.
2Strength
If a multilayer structure with porous support substrate and dense ceramic layer is used to maintain strength, then membrane strength is improved, but internal fracture of the porous substrate reduces fracture toughness and sintering complexity decreases yield
Solution Approach 1:
The patent applies local quality by creating a dense ceramic layer with specific properties on the surface of the porous substrate. The dense layer has high fracture toughness and serves as a protective barrier, while the porous substrate provides overall structural support. Each layer is optimized for its specific function, with the dense layer compensating for the lower fracture toughness of the porous substrate.
3Productivity
If barium strontium cobalt iron oxide (BSCF) is used due to its high ionic conductivity, then oxygen transport rate is improved, but its low catalytic ability results in surface reaction rate being less than oxygen ion transport speed at lower temperatures, leading to drops in oxygen transport
Solution Approach 1:
The patent combines BSCF material with catalytically active materials to create a composite oxygen transport membrane. The BSCF component provides high ionic conductivity for efficient oxygen ion transport, while the catalytically active component enhances the surface reaction rate. This composite approach ensures that both the oxygen ion transport speed and surface reaction rate are sufficiently high, preventing oxygen transport drops at lower operating temperatures.
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 solution effectively improves oxygen separation efficiency at low temperatures, increases oxygen transport flow rate by over 10% at 900°C and 60% at 700°C, and reduces production costs by simplifying the manufacturing process and avoiding thermal stress rupture.
Implementation Method 1
Oxygen transport membrane is usually made of dense ceramic material having a high temperature oxygen ion conductive function, and the material properties of the dense ceramic material operating at temperature above 600° C. has very high oxygen ion selectivity
Implementation Method 2
barium strontium cobalt iron oxide (Ba0.5Sr0.5Co0.8Fe0.2O3-δ, BSCF) has a highest Ionic conductivity, leading to a high oxygen transport rate per unit area in theoretical value
Implementation Method 3
a pure ion conductor oxygen transport membrane with a mechanism in which the oxygen may obtain electrons and dissociate into oxygen ion, and the oxygen ion conductor reverted back into the oxygen through loss of the electron
Implementation Method 4
the complexity of the process and uncertain success rate of sintering may also cause the yield to decrease
Data Source
AI summary
A composite material type oxygen transport membrane and its preparation method are disclosed. The composite material that is an ionic-electronic mixed conducting material having high ionic conductivity is stirred into slurry and formed into a thin strip-shaped green tape substrate through tape casting to obtain a predetermined half-finished substrate, and then sintered to form the half-finished substrate into a conductive function type oxygen ion conducting substrate, followed by choosing small particle shaped highly catalyzed ionic-electronic mixed conducting material to be evenly adhered to at least one side surface of the conductive function type oxygen ion conducting substrate to form a reductive function type oxygen ion conducting layer. The reductive function type oxygen ion conducting layer and the conductive function type oxygen ion conducting substrate are then bonded to produce a composite material type oxygen transport membrane element.