Lactic acid enrichment with inorganic nanofiltration and molecular sieving membranes by pervaporation

Duke, Mikel C., Lim, Agnes, Castro da Luz, Sheila and Nielsen, Lars (2008) Lactic acid enrichment with inorganic nanofiltration and molecular sieving membranes by pervaporation. Food And Bioproducts Processing, 86 4: 290-295. doi:10.1016/j.fbp.2008.01.005

Author Duke, Mikel C.
Lim, Agnes
Castro da Luz, Sheila
Nielsen, Lars
Title Lactic acid enrichment with inorganic nanofiltration and molecular sieving membranes by pervaporation
Journal name Food And Bioproducts Processing   Check publisher's open access policy
ISSN 0960-3085
Publication date 2008-01-01
Year available 2008
Sub-type Article (original research)
DOI 10.1016/j.fbp.2008.01.005
Open Access Status
Volume 86
Issue 4
Start page 290
End page 295
Total pages 6
Editor John Perkins
Richard Wakeman
Place of publication Oxford, U. K.
Publisher Elsevier
Language eng
Subject C1
090404 Membrane and Separation Technologies
860199 Processed Food Products and Beverages (excl. Dairy Products) not elsewhere classified
Abstract Lactic acid is a valuable product in the food industry, but requires expensive complex systems to purify. Porous inorganic membranes have high fluxes and water separation potential and are driven only by pressure difference without the need for added chemicals. Here we show the application of readily available γ-alumina (nanofiltration), and the more advanced molecular sieve silica membranes, to enrich lactic acid for product use by selectively depleting water through the membrane. The alumina membranes showed flux starting at 6 kg m−2 h−1, reducing to 1 kg m−2 h−1 after 250 min due to pore blocking of lactic acid. The membrane acted to remove water from the 15 wt% feed, with permeate lactic acid concentration at 2 wt% corresponding to a water selectivity factor of 9. Silica membranes on the other hand exhibited a water selectivity factor up to 220 (a rejection coefficient of 0.995) with lactic acid in the permeate as low as 0.08 wt% after regeneration with an overall stable flux of 0.2 kg m−2 h−1. The strong surface charge and wider pore size of the alumina membrane enabled a slow pore blocking mechanism, with flux dropping towards that of the silica membrane. The silica membrane was therefore the choice technology as the tight pore spaces inhibited lactic acid from entering and the charge-neutral surface leading to a more stable separation not subject to pore blocking. Performance results allowed calculation of membrane area for industrial separation. Flux improvements and longer term studies are needed to improve silica membrane commercial attraction.
Keyword Lactic acid
Inorganic membrane
Molecular sieve
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2009 Higher Education Research Data Collection
Australian Institute for Bioengineering and Nanotechnology Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 12 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 20 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 07 Apr 2009, 19:47:16 EST by Mrs Jennifer Brown on behalf of Aust Institute for Bioengineering & Nanotechnology