Separation and Purification Technology, Vol.116, 124-130, 2013
PAN hollow fibre membranes with triacetyl-beta-cyclodextrin for the removal of pesticides from citrus essential oils
Polyacrylonitrile (PAN) hollow fibre membranes, loaded with triacetyl-beta-CD, were prepared according to the dry-wet spinning technique by non-solvent induced phase inversion a. The resulting membranes were tested for the reduction of pesticides from citrus essential oils. Results concerning the selection of the polymeric membrane material, the treatment of citrus essential oils with the prepared membranes and their selectivity towards specific pesticides (imazalil, thiabendazole and o-phenylphenol) were analyzed and discussed. In selected operating conditions average permeate fluxes between 15 and 30 kg/m(2) h were obtained for the analyzed essential oils (orange, lemon and mandarin). The removal of imazalil from these essential oils was in the range 49.7-53%. For the orange essential oil a 48.9% removal of thiabendazole was observed. On the contrary, no significant reduction of o-phenylphenol (lower than 5%) was detected in the permeate fractions coming from the treatment of all the investigated essential oils. The volatile fraction composition in the permeate of lemon essential oil treated with the prepared membranes remained unchanged if compared with that of the initial feed. Therefore, PAN membranes loaded with triacetyl-beta-CDs did not modify the organoleptic and physicochemical characteristics of the essential oil. On the contrary, the treatment of orange essential oil with ceramic membranes having MWCO of 750 and 1000 Da produced a removal of the volatile fraction of 5-10%, a removal of non-volatile fraction in the range of 10-50% (especially in terms of cumarines) and a removal of carotenoids higher than 90%. (c) 2013 Elsevier B.V. All rights reserved.