Process for the manufacture of low-phosphorus or phosphorus-free detergents containing aluminosilicates

A process for the manufacture of a low phosphorus or phosphorus-free spray dried detergent powder containing less than 6% by weight calculated as phosphorus, of phosphorus-containing compounds, from 5% to 30% by weight of at least one surface-active compound selected from the group consisting of anionic surface-active compounds, non-ionic surface-active compounds and zwitterionic surface-active compounds of which from 2.3% to 14% by weight is said nonionic surface-active compounds, from 15% to 90% by weight of water-soluble builder salts, from 0 to 50% by weight of other detergent powder additives, and from 5% to 50% by weight of at least one finely-dispersed water-insoluble silicate compound containing at least some combined water and having primary particles in the size range of from 100.mu. to 0.1.mu. and a calcium binding powder when measured at 22.degree. C. by the Calcium Binding Power Test Method set out in the specification, of from 100 to 200 mg CaO/gm of anhydrous active substance and the formula on the anhydrous basis

• (M.sub.2/n O).sub.x.Me.sub.2 O.sub.3.(SiO.sub.2).sub.y
• where M is a cation of the valence n, selected from the group consisting of sodium and potassium, x is a number from 0.7 to 1.5, Me is a member selected from the group consisting of aluminum and boron, and y is a number from 0.8 to 6, comprising the steps of spraying an aqueous slurry of at least 50% by weight of the total solids of the final spray dried detergent, of detergent ingredients, into a fall space while passing a large volume of air therethrough at an inlet temperature in excess of 150.degree. C. and simultaneously injecting into said fall space, a powder comprising at least 25% by weight of the total amount of said silicate compound, at a rate in proportion to the rate of said spraying whereby the desired total solids ratio of ingredients in said spray dried detergent powder is maintained, and recovering said spray dried detergent powder.

A process for the manufacture of a low phosphorus or phosphorus-free spray dried detergent powder containing less than 6% by weight calculated as phosphorus, of phosphorus-containing compounds, from 5% to 30% by weight of at least one surface-active compound selected from the group consisting of anionic surface-active compounds, nonionic surface-active compounds and zwitterionic surface-active compounds of which from 29.5% to 100% by weight of said surface-active compounds are nonionic surface-active compounds, from 15% to 90% by weight of water-soluble builder salts, from 0 to 50% by weight of other detergent powder additives, and from 5% to 50% by weight of at least one finely-dispersed water-insoluble silicate compound containing at least some combined water and having primary particles in the size range of from 100.mu. to 0.1.mu. and a calcium binding power when measured at 22.degree. C. by the Calcium Binding Power Test Method set out in the specification, of from 100 to 200 mg CaO/gm of anhydrous active substance and the formula on the anhydrous basis

• (M.sub.2/n O).sub.x.Me.sub.2 O.sub.3.(SiO.sub.2).sub.y
• where M is a cation of the valence n, selected from the group consisting of sodium and potassium, x is a number from 0.7 to 1.5, Me is a member selected from the group consisting of aluminum and boron, and y is a number from 0.8 to 6, comprising the steps of spraying an aqueous slurry of at least 50% by weight of the total solids of the final spray dried detergent, of detergent ingredients, into a fall space while passing a large volume of air therethrough at an inlet temperature in excess of 150.degree. C. and simultaneously injecting into said fall space, a powder comprising at least 25% by weight of the total amount of said silicate compound, wherein at least part of said non-ionic surface-active compound is combined with said powder comprising said silicate compound in a ratio of from 0.11 to 0.3 parts by weight of said non-ionic surface-active compound per 1 part by weight of said silicate compound, said powder being injected at a rate in proportion to the rate of said spraying whereby the desired total solids ratio of ingredients in said spray dried detergent powder is maintained, and recovering said spray dried detergent powder.