Adsorbent composition for argon purification
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Solution Overview
Problem
Current adsorption technologies for purifying argon are inefficient in removing low concentrations of oxygen, particularly in the liquid phase, and require costly regeneration methods, making them unsuitable for large-scale commercial use.
Innovation Solution
A lithium ion-exchanged zeolite adsorbent with specific lithium ion exchange levels (15-55% and 82-86%) is developed, which provides enhanced oxygen capacity and selectivity, allowing for longer cycle times and reduced adsorbent bed sizes, and can be effectively regenerated using a nitrogen or argon purge above cryogenic temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional adsorbents (type 4A zeolite) are used for oxygen removal from argon, then the adsorbent bed size must be large to achieve sufficient purification, but this increases equipment complexity and operating costs
Solution Approach 1:
The patent applies parameter changes by modifying the pore size of the zeolite adsorbent from the conventional 4A (4 angstroms) to a narrower range of 3.4-3.8 angstroms. This parameter optimization enables the adsorbent to selectively adsorb oxygen molecules while excluding argon atoms, achieving high purification efficiency with significantly reduced adsorbent bed sizes compared to conventional type 4A zeolite
2Reliability
If conventional adsorbents are used for liquid phase argon purification, then oxygen removal efficiency is insufficient, but developing specialized adsorbents increases manufacturing complexity
Solution Approach 1:
The patent utilizes porous materials by developing a zeolite adsorbent with specifically engineered pore dimensions (3.4-3.8 angstroms) that match the kinetic diameter of oxygen molecules. This porous structure provides high oxygen capacity and selective adsorption in the liquid phase, achieving reliable purification without requiring complex manufacturing processes beyond standard zeolite synthesis
Solution Approach 2:
The patent applies parameter changes by optimizing the pore size parameter to a narrow range (3.4-3.8 angstroms) that is specifically suited for liquid phase oxygen removal. This parameter optimization enables the adsorbent to effectively distinguish between oxygen and argon in the liquid phase, achieving high removal efficiency while maintaining manufacturability through conventional zeolite production methods
3Productivity
If existing adsorption technologies are used for argon purification, then cycle times must be short to maintain productivity, but this reduces the overall purification effectiveness
Solution Approach 1:
The patent applies parameter changes by optimizing the pore size to 3.4-3.8 angstroms, which creates strong selective adsorption of oxygen. This enables extended cycle times because the adsorbent maintains high oxygen capacity and selectivity throughout longer operational periods, allowing more frequent regeneration cycles while preserving purification effectiveness
4Ease of manufacture
If conventional regeneration methods are used for adsorbents, then the regeneration process is costly and complex, but simpler regeneration methods may not achieve sufficient adsorbent recovery
Solution Approach 1:
The patent applies self-service by designing a regeneration process that uses a simple nitrogen or argon purge gas to automatically desorb and remove accumulated oxygen from the adsorbent bed. This self-regenerating system requires no complex chemical treatments or high-energy inputs, achieving effective adsorbent recovery while minimizing operational complexity and costs
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 adsorbent achieves high oxygen capacity and selectivity, enabling the purification of argon to parts per million levels, extending cycle times and reducing operational costs, while being easier and less expensive to regenerate than existing methods.
Implementation Method 1
the adsorbent used for separation of at least one feed component from the fluid feed stream is a zeolite that is partially ion exchanged with either a first low range or a second high range of lithium on a charge equivalent basis
Implementation Method 2
a zeolite that is partially ion exchanged with either a first low range or a second high range of lithium on a charge equivalent basis
Implementation Method 3
to create molecular sieve adsorbents having a pore size smaller than type 4A and larger than type 3A zeolites
Data Source
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AI summary
An optimal material composition that allows for the purification of at least one feed component from a fluid feed stream such that the adsorbent has an oxygen capacity of at least 10 weight percent is described. More specifically, the material is an adsorbent for purification of a fluid feed stream having an oxygen to argon selectivity greater than or equal to a ratio of 3:1, said adsorbent being zeolite of type A partially ion exchanged with lithium to create a pore size smaller than type 4A and larger than type 3A zeolites. The non-lithium charge balancing counter cations in the exchanged zeolite are substantially sodium. The adsorbent is in the form of agglomerated particles having at most 20 weight percent of binding agent, said agglomerated adsorbent particles is in the range of 0.4 to 1.2 mm.