EDTA: a synthetic draw solute for forward osmosis

作者：Lutchmiah Kerusha^*; Post Jan W; Rietveld Luuk C; Cornelissen Emile R

来源：Water Science and Technology, 2014, 70(10): 1677-1682.

DOI：10.2166/wst.2014.424

• draw solution
• EDTA
• forward osmosis
• reverse solute leakage

The draw solution is the driving force of the forward osmosis (FO) process; however, the solute loss of the draw solute to the feed side is a general, financial limitation for most applications. The anthropogenic amino acid ethylenediaminetetraacetic acid (EDTA) was investigated as a draw solution for FO. At concentrations of approximately 1.0 osmol/kg, EDTA demonstrated comparable water fluxes (J(v) = 5.29 L/m(2) h) to the commonly used salt, NaCl (J(v) = 4.86 L/m(2) h), and both produced better water fluxes than glucose (J(v) = 3.46 L/m(2) h). EDTA showed the lowest solute loss with J(s) (reverse solute loss or solute leakage) = 0.54 g/m(2) h. The molecular weight, degree of ionisation and charge of EDTA played a major role in this efficiency and EDTA was therefore well rejected by the membrane, showing a low J(s)/J(v) ratio of 0.10 g/L. Owing to the low solute loss of EDTA and its resistance to biodegradation, this compound has the potential to be used as a draw solute for FO during long periods without requiring much replenishment.

• 出版日期2014