A process for preparing a thin film composite membrane, comprising: (a) preparing an aqueous phase comprising a polyamine, and an organic phase comprising a polyfunctional acid halide, wherein the aqueous phase or organic phase or both further include a flux enhancing combination that comprises: (i) a metal chelate additive containing a bidentate ligand and a metal atom or metal ion; and (ii) a dialkyl sulfoxide; (b) applying the aqueous phase to a surface of a porous support membrane to form a coated support membrane; and (c) applying the organic phase to the coated support membrane and interfacially polymerizing the polyamine and the polyfunctional acid halide to form a discrimination layer of a thin film composite membrane comprising the porous support membrane and the discrimination layer, the thin film composite membrane having a water flux that is greater than the water flux of a thin film composite membrane prepared in the absence of the water flux enhancing combination, wherein the thin film composite membrane has a flux of at least 34 l/h/m 2 (20 gfd) determined by exposing the membrane to deionized water containing 2,000 ppm NaCl at a temperature of 25 °C and a pressure of 10 bar (150 psi), wherein an amount of metal chelate additive in the aqueous phase or organic phase is 0.001 wt% to 1 wt% based on the weight of the aqueous phase or the organic phase, and wherein an amount of dialkyl sulfoxide in the aqueous phase or organic phase is 0.5 wt% to 5 wt% based on the weight of the aqueous phase or the organic phase; wherein the bidentate ligand is selected from among: and wherein each of R 1 , R 2 , R 3 , R 4 and R 5 separately is selected from among a Ci-C 10 alkyl, a halogenated C 1 -C 10 alkyl, a 5-membered aromatic ring, a 6-membered aromatic ring, an aromatic bicyclic ring system containing two fused 6-membered rings, and an aromatic bicyclic ring system containing a 5-membered ring fused to a 6-membered aromatic ring. (a) preparing an aqueous phase comprising a polyamine, and an organic phase comprising a polyfunctional acid halide, wherein the aqueous phase or organic phase or both further include a flux enhancing combination that comprises: (i) a metal chelate additive containing a bidentate ligand and a metal atom or metal ion; and (ii) a dialkyl sulfoxide; (i) a metal chelate additive containing a bidentate ligand and a metal atom or metal ion; and (ii) a dialkyl sulfoxide; (b) applying the aqueous phase to a surface of a porous support membrane to form a coated support membrane; and (c) applying the organic phase to the coated support membrane and interfacially polymerizing the polyamine and the polyfunctional acid halide to form a discrimination layer of a thin film composite membrane comprising the porous support membrane and the discrimination layer, the thin film composite membrane having a water flux that is greater than the water flux of a thin film composite membrane prepared in the absence of the water flux enhancing combination, wherein the thin film composite membrane has a flux of at least 34 l/h/m 2 (20 gfd) determined by exposing the membrane to deionized water containing 2,000 ppm NaCl at a temperature of 25 °C and a pressure of 10 bar (150 psi), wherein an amount of metal chelate additive in the aqueous phase or organic phase is 0.001 wt% to 1 wt% based on the weight of the aqueous phase or the organic phase, and wherein an amount of dialkyl sulfoxide in the aqueous phase or organic phase is 0.5 wt% to 5 wt% based on the weight of the aqueous phase or the organic phase; wherein the bidentate ligand is selected from among: and wherein each of R 1 , R 2 , R 3 , R 4 and R 5 separately is selected from among a Ci-C 10 alkyl, a halogenated C 1 -C 10 alkyl, a 5-membered aromatic ring, a 6-membered aromatic ring, an aromatic bicyclic ring system containing two fused 6-membered rings, and an aromatic bicyclic ring system containing a 5-membered ring fused to a 6-membered aromatic ring. <EOS>