USE OF ADSORBENTS FOR RECOVERY OF ACETIC ACID FROM AQUEOUS SOLUTIONS.

Measurements have been made of the uptake of acetic acid and water from low-pH aqueous solution onto polymeric adsorbents and activated carbons. Capacities for acetic acid are determined by the chemical nature of the adsorbent, in addition to surface area. With Lewis-base polymers such as pyridine and tertiary-amine resins, the capacity indicates that internal basic groups come into play. For activated carbon adsorbents, the presence of hetero-atoms results in a greater adsorption per unit surface area. In addition to composite isotherms, isotherms were obtained for acetic acid and water individually by use of gas-chromatographic and Karl Fischer techniques for analyses of both bulk solution and adsorbed phases The amount of water uptake is a critical factor in the design of adsorption processes for recovery of acetic acid. Selectivity is governed by co-adsorption of water and pore volume and swelling tendencies of the adsorbent. Swelling tendencies are particularly important for polymers. Activated carbons and pyrolyzed polymers give better selectivity than do common polymeric adsorbents.

USE OF ADSORBENTS FOR RECOVERY OF ACETIC ACID FROM AQUEOUS SOLUTIONS. Academic Article