Assessing the Premature Aging of Chabazite in Natural Gas Drying by TSA

TL;DR

This paper investigates how high temperatures and hydrocarbons cause aging in chabazite used for drying natural gas, affecting its performance.

Contribution

The study reveals how hydrocarbon exposure and thermal stress degrade chabazite structure and performance during natural gas drying.

Findings

High temperatures and n-heptane vapor cause mild crystalline degradation in chabazite.

Hydrocarbons adsorb in pores and surfaces, worsening textural properties and increasing carbon content.

n-Heptane vapor exposure leads to more homogeneous adsorbent composition than liquid addition.

Abstract

Ongoing research on adsorbent deactivation in drying
processes
has unveiled crucial insights into the loss of performance with prolonged
use. Our study builds on previous work by examining the effects of
high temperatures, hydrocarbon exposure, and cycle duration on chabazite
adsorbents with a Si/Al ratio of approximately 2 and in the sodium
form. By aging the material under controlled conditions, we assessed
the impact on its structural and textural properties. Our findings
reveal that maintaining high temperatures, coupled with exposure to n-heptane vapor, induces a mild degradation of the crystalline
structure, with more pronounced effects during longer aging periods.
Notably, hydrocarbons play a critical role in adsorbent deactivation,
adsorbing in both the inner pores and the outer surface of the zeolite.
This leads to a deterioration of the textural characteristics, which
directly correlates with an increase in the carbon content of the
bulk material. Additionally, samples exposed to n-heptane vapor exhibited a more homogeneous composition compared
to those subjected to manual liquid n-heptane addition.
Overall, the degree of degradation varies among aged samples, indicating
the need for tailored applications based on specific aging conditions.

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