Solvent recovery from soybean oil/n-hexane mixtures using hollow fiber membrane

Abstract

-In this work, the separation of refined soybean oil/n-hexane mixtures was investigated using a commercial hollow fiber ultrafiltration membrane 50 kDa. Three alcohols with different chain lengths were tested for the conditioning of the membrane; n-propyl alcohol showed the highest n-hexane permeate flux after conditioning. There was a decrease in the rejection and an increase in permeate flux over time. This behavior may be related to swelling and membrane plasticization by the oil. Rejections from 10.0 to 28.7% and total permeate fluxes from 12.2 to 65.3 kg/m 2 h were observed. An increase in the oil/n-hexane mass ratio and the pressure caused an increase in the rejection and permeate total flux for most assays. No degradation was observed in the membrane module.

Desolventizing organic solvent-soybean oil miscella using ultrafiltration ceramic membranes

“…Table 1 shows the specifications of the membranes used in this work. The choice of the membranes investigated in this work was based on previous experience of our research group [5][6][7][8][9].…”

“…Briefly, the module was completely filled with n-butanol at room temperature and the membrane was kept soaked in the solvent for 24 h. After removing n-butanol, 3 rinses with n-hexane were carried out, and then the module was maintained filled with n-hexane for 24 h prior to the assays [7]. …”

“…Tres et al [7] investigated the best solvent for the conditioning step in an attempt to increase n-hexane flux in a 50 kDa polymeric hollow fiber membrane. The authors tested a homologous series of alcohols (ethanol, n-propanol and n-butanol) and n-propanol was the one that provided the largest n-hexane flux.…”

“…The first report on membrane separation for oil/solvent mixtures was focused on using polymeric membranes, which present as main disadvantages inherent incrustation, plasticization and swelling when in contact with solutes and organic solvents, hence leading to the reduction of its industrial life time [5][6][7][8][9][10][11][12]. Ceramic membranes, in spite of the higher initial cost, present a great potential application in the separation of solutes from non-aqueous solutions, since the interactions of the solutes and solvents with the membrane ceramic material are much smaller when compared with polymeric membranes [13][14][15].…”

Solvent recovery from soybean oil/n-butane mixtures using a hollow fiber ultrafiltration membrane

“…This study is part of two studies of new technologies for extraction of essential and vegetable oils based on pressurized and liquified gases (Oliveira et al, 2012;Novello et al, 2013;Tres et al, 2009b), and the use of the membrane separation process for recovery of solvents used in such extraction processes (Oliveira et al, 2011;Tres et al, 2009aTres et al, , 2010Tres et al, , 2012aTres et al, and 2012b. The final purpose of these works is the application of this technology to aid solvent recovery in oil extraction plants.…”