Preparation of environmentally acceptable scale inhibitors

The method of claim 21, wherein the scale inhibitor demonstrates greater than about 40% biodegradation in 28 days when tested according to method OECD 306.

A method, comprising:

• controlling the degree of phosphonoalkylation of one or more amino acid species having at least four active hydrogen atoms to produce an effective scale inhibitor composition including at least one alkylphosphonated amino acid species, wherein the at least one alkylphosphonated amino acid species includes greater than 50 weight percent di-substituted alkyl phosphonated amino species and demonstrates greater than about 20% biodegradation in 28 days when tested according to method OECD 306.

A scale inhibitor formulation, comprising:

• a solvent;
• a scale inhibitor composition within the solvent, wherein the scale inhibitor composition includes at least one alkyl phosphonated amino acid species, wherein greater than 50 weight percent of the at least one alkyl phosphonated amino acid species is a lysine functionality that is di-substituted with alkyl phosphonate groups, and wherein the scale inhibitor composition demonstrates greater than about 20% biodegradation in 28 days when tested according to method OECD 306.