Using strong acid–cation exchange resin to reduce potassium level in molasses vinasses

Abstract

Molasses-based distilleries are one of the most vulnerable to pollution industries, which always generate large volumes of high strength vinasse. Recently, one of the most effective re-applications/reuse of vinasse is concentrating the molasses vinasse to prepare as fodder additive for animal food. However, the dosage of molasses vinasse to be added as animal feed is always limited because of the unexpectedly high potassium content in molasses vinasse. In present study, potassium ions were firstly extracted from molasses vinasses using a strong acid–cation exchange resin, and then desorbed from the resin and dissolved into the eluate by H 2SO 4 solution as the strong acid–cation exchange resin was regenerated. Finally, evaluation to recycle and reuse the mother liquor (once-used eluant), after extracting K 2SO 4 crystals from the eluant, was investigated. Results indicated that using the mother liquor to elute the resin column which absorbing K + from molasses vinasse was a potential means for industrial production of potassium salt. Meanwhile, the molasses vinasse which has removed most potassium ions might be used as animal feed.