Equilibrium Theory for Adiabatic Desorption of Bulk Binary Gas Mixtures by Purge

Journal Article · Mon Apr 01 00:00:00 EST 1985 · Ind. Eng. Chem. Process Des. Dev.; (United States)

DOI:https://doi.org/10.1021/i200029a023· OSTI ID:5383606

Sircar, S; Kumar, R

A local equilibrium theory for adiabatic desorption of bulk binary gas mixtures by isobaric purge is developed. The model is used for evaluating the effect of adsorption selectivity, the strength of sorption, and the purge gas composition on the desorption process. Examples of the desorption of CO/sub 2/ from mixtures with CH/sub 4/, N/sub 2/, and H/sub 2/ are considered. Analytical equations to describe isothermal desorption of binary Langmuir adsorbates are derived. Desorption profiles obtained from isothermal and adiabatic models are compared. It is demonstrated that (a) desorption of a more strongly adsorbed species (component 1) by purging with a less strongly species (component 2) is more efficient when component 1 is less selectively adsorbed; (b) an adsorbent which exhibits higher adsorption capacity and selectivity for component 1 also requires more purge gas to clean the column and thus the adsorbent may not be preferred for separation by PSA process; (c) composition of the purge gas is important only to determine the level of residual component 1 at the end of the purge step; and (d) assumption of column isothermality during the purge process can severely underestimate the quantity of the purge gas requirement of an adiabatic column.

• Research Organization: Air Products and Chemicals, Inc., Allentown, Pennsylvania
• OSTI ID: 5383606
• Journal Information: Ind. Eng. Chem. Process Des. Dev.; (United States), Vol. 24:2
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBON DIOXIDE
DESORPTION
ADIABATIC PROCESSES
ADSORBENTS
ADSORPTION
CHEMICAL COMPOSITION
EQUATIONS
EQUILIBRIUM
HYDRIDES
HYDROGEN
ISOTHERMAL PROCESSES
METHANE
MIXTURES
NITRIDES
NITROGEN
ALKANES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
DISPERSIONS
ELEMENTS
HYDROCARBONS
HYDROGEN COMPOUNDS
NITROGEN COMPOUNDS
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
SORPTION
400201* - Chemical & Physicochemical Properties