Abstract: A method for removal of sulfide from a stream, the method comprising preparing a metal-chelant complex, designated M-Yn, where M is a divalent or trivalent cation, Y comprises a gluconic acid, glucaric acid or derivative thereof, and n is from about 1 to about 3; contacting a mixture comprising M-Yn and a base with a sulfide stream under conditions suitable for the formation of a metal-sulfide species; and contacting the metal-sulfide species with an oxidizing agent to form a soluble metal sulfide species. A method for removal of sulfide from a stream, the method comprising preparing a sulfide scavenging mixture comprising a base and a metal-complex characterized by Structure (I); contacting the sulfide scavenging mixture with a sulfide stream under conditions suitable for the formation of a metal-sulfide species; and contacting the metal-sulfide species with an oxidizing agent to form a soluble metal sulfide species.

Abstract: A method for removal of sulfide from a stream, the method comprising preparing a metal-chelant complex, designated M-Yn, where M is a divalent or trivalent cation, Y comprises a gluconic acid, glucaric acid or derivative thereof, and n is from about 1 to about 3; contacting a mixture comprising M-Yn and a base with a sulfide stream under conditions suitable for the formation of a metal-sulfide species; and contacting the metal-sulfide species with an oxidizing agent to form a soluble metal sulfide species. A method for removal of sulfide from a stream, the method comprising preparing a sulfide scavenging mixture comprising a base and a metal-complex characterized by Structure I; contacting the sulfide scavenging mixture with a sulfide stream under conditions suitable for the formation of a metal-sulfide species; and contacting the metal-sulfide species with an oxidizing agent to form a soluble metal sulfide species.

Abstract: A method of purifying a produced water comprising contacting a produced water stream with a composition comprising a (i) a chelant; (ii) an oxidizing agent; and (iii) a surfactant under conditions suitable for the formation of a purified produced water. A composition for purifying produced water comprising (i) a biochelant in an amount of from about 1 wt. % to about 10 wt. %: (ii) an oxidizing agent in an amount of from about 3 wt. % to about 50 wt. %; (iii) a surfactant in an amount of from about 0.1 wt. % to about 70 wt. % wherein the weight percentage is based on the total weight of the composition; and (iv) a solvent.

Abstract: A multifunctional wellbore servicing additive composition includes a biochelant and at least one compound selected from the group consisting of acid, oxidizer, protectant, and surfactant. A method of servicing an oilwell includes placing downhole a composition comprising a biochelant and at least one compound selected from the group consisting of acid, oxidizer, protectant, and surfactant.