Chelating Agents as Detergent Builders

Two chelating detergent builders (o) tripolyphosphate (TPP) and (b) nitrilotriacetate (NTA). Each is shown com- 

So what has replaced phosphates in syndets A quick survey of laundry products shows that many of them use suspended sodium carbonate, Na2C03, as a builder. Carbonates precipitate out hard-water ions as a fine, granular precipitate, a process represented in Equation (6.17) silicates also precipitate out hard-water ions [Equation (6.18)] and have found limited use as phosphate replacements  

More recently, zeolites or aluminosilicates have also been used to sequester these ions. (See Section 15.5 for more on the structure and function of aluminosilicates.) Phosphates themselves are still used (although limited to 8.7% in laundry detergents in many states), particularly in industrial-strength cleaners and in dishwasher detergents. 

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