Esters of volatile organic flavor compounds were recovered from dilute aqueous solutions by pervaporation; ethyl acetate (
EA
), propyl acetate (PA), and butyl acetate (BA). A surface-modified tube-type alumina membrane was used to evaluate the effects of the feed concentration (0.15–0.60 wt%) and feed temperature (30–50°
C
) on the separation of
EA
, PA, and BA from dilute aqueous solutions. The permeation flux increased with the increasing feed ester concentration and operating temperature. The separation factors for the 0.15–0.60 wt% feed solutions of
EA
, PA, and BA at 40°
C
were in the range of 66.
9
–78.
9
,
86
.0–89.0, and 117.1–
94
.7, respectively.
EA
, PA, BA in the permeate were concentrated up to
9
.13–32.26, 11.44–34.
95
, and 14.96–36.37 wt%, respectively. Due to the high selectivity, phase separation occurred in the permeate stream because the ester concentration in the permeate was above the saturation limit. The fluxes of
EA
, PA, and BA at 0.60 wt% feed concentration and 40°
C
were 254, 296, and 318 g/m
2·h, which are much higher than those obtained with polymer membranes. In the case of PDMS at feed concentrations of 90–4800 pp, and at 45°
C
, it was reported that the permeate flux of
EA
was 1.1–58 g/m
2·h. Compared to PDMS, the surface-modified membrane investigated in this study showed a much higher flux of esters.
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