Block detergent containing nitrilotriacetic acid

A process for producing a phosphate-free solid, block detergent comprising the steps of:

• a. preparing an aqueous alkaline solution containing from about 5% to about 40% by weight of the formulation of a first alkali metal containing compound selected from the group consisting of alkali metal hydroxides, alkali metal silicates and mixtures of alkali metal hydroxides and silicates, wherein, when the aqueous alkaline solution contains alkali metal hydroxides, the alkali metal hydroxides must include sufficient potassium hydroxide to constitute from about 0.1% to about 30% by weight of the formulation;
• b. mixing from about 5% to about 60% by weight of the formulation of an alkali metal salt of nitrilotriacetic acid into the aqueous alkaline solution to form a slurry;
• c. adding from about 0.1% to about 10% by weight of the formulation of an acid selected from the group consisting of propionic acid, nitrilotriacetic acid, ethylene diamine tetra-acetic acid, diethylene triamine pentaacetic acid, hydroxy ethylene diamine tetra-acetic acid, amino acids, polyamino acids, amino tri(methylene phosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, diethylene triamine penta(methylene phosphonic acid), oxalic acid, succinic acid, adipic acid, citric acid, maleic acid, malic acid, fumaric acid, tartaric acid, gluconic acid, benzoic acid, ascorbic acid, sorbic acid, linear alkylbenzene sulfonic acid, polyacrylic acid and boric acid to the slurry;
• d. mixing from about 5% to about 25% by weight of the formulation of a second alkali metal containing compound selected from the group consisting of alkali metal sulfates, alkali metal carbonates and mixtures of alkali metal sulfates and alkali metal carbonates into the slurry;
• and
• e. curing the slurry.