Builders, detergent pyrophosphate

Phosphates are considered to be the most cost-effective detergent builder available, combining the properties of high efficacy (calcium sequestration, antiredeposition, buffering of pH), low toxicity, and relatively low cost. Phosphates are compatible with a wide variety of processing methods and product forms, which allows their use in powders, liquids, and bars. Although sodium tripolyphosphate (STPP) is the most common phosphate builder, sodium pyrophosphate is also used in some countries. In Asia, Latin America, and Africa, phosphates are the predominant detergent builders used. 

Condensed potassium phosphates have been used as builders in Hquid detergents. The compound tetrapotassium pyrophosphate [7320-34-5] which forms by dehydrating K HPO at 400°C, was used. 

Tetrasodium pyrophosphate [7722-88-5] Na4P20y, is another important primary builder and detergent. In sequestration, it is not quite as effective as sodium tripolyphosphate and its usage in heavy-duty laundry powders has declined in recent years. Functionally, tetrasodium pyrophosphate is both a builder for surfactants (ie, water softener) and alkaH. 

Scouring may be conducted on jigs, boil-off machines, or kettles, depending on fabric weight, constmction, and crease tendency ia the rope form. A combination of a synthetic detergent and soda ash is usually used and scouring is conducted at 85—100°C. Certain nylon blends may require less stringent conditions and the use of less alkaline builders, such as tetrasodium pyrophosphate. 

Most of the world production of phosphates goes into fertilizer, but some is used as detergent builders (Section 7.7). In toothpastes, calcium pyrophosphate has proved effective as a mild abrasive in eliminating tartar, while Na2[FP03], made by reaction of NaF with cyclic sodium metaphosphates (NaP03), is widely used as a fluoridating agent to suppress dental caries (Section 12.3). A minor amount of rock phosphate is used to make elemental phosphorus by reduction with coke in the presence of silica in the electric furnace (see Section 17.7) ... 

Tetrasodium pyrophosphate is used as a water softener and as a soap and detergent builder. 

BORCO AP is a versatile aid in scouring as well as in dyeing all fiber substrates. It possesses low foaming characteristics and has good detergent activity when used with alkaline builders such as Tetra sodium pyrophosphate (TSPP), soda ash or caustic soda. Maximum scouring results are obtained with the use of TSPP. 

Potassium phosphates, particularly tetrapotassium pyrophosphate, K4P2O7, are considerably more soluble than their sodium analogs. They have been used as builders in liquid detergents. 

The builders, such as silicates, pyrophosphates (Na4P207) and tripolyphosphates, are generally incorporated into detergent formulations to improve their performance. They produce mildly alkaline solutions, which are favorable to detergent action. They also form soluble non-adsorbed complexes with the metal ions such as Ca2+ and Mg2+, which... 

Ammonium carbonate Citric acid Methyl vinyl ether/maleic acid copolymer Nitrilotriacetic acid Oxidized cellulose PEG-2 cocomonium chloride Sodium disilicate Sodium metaphosphate Sodium sesquicarbonate Sodium silicoaluminate Tetrapotassium pyrophosphate Tetrasodium EDTA Zeolite Zeolite synthetic detergent builder, household cleaners Potassium silicate detergent builder, laundry powders Sodium sulfate... 

Two forms of sodinm phosphates have been nsed as detergent builders sodium tripolyphosphate (STPP), which is the more commonly nsed form, and tetrasodium pyrophosphate (TSPP). 

Another pyrophosphate, tetrapotassium pyrophosphate (K4P2O7), also known as tetrapotassium diphosphate, is used as a builder in liquid detergent formulations at levels in the range 20-25% despite its higher cost [2]. These levels are due to its significantly higher water solubility properties when compared to the sodium salt as well as the stability of the pyrophosphate anion. Tetrapotassium pyrophosphate functions as a dispersant and binds multivalent cations, keeping them in solution. 

Sodium tripolyphosphate is the major builder ingredient in heavy duty laundry detergents, automatic dishwashing compounds, and industrial and institutional cleaners. In liquid consumer laundry detergents, sodium citrate has displaced tetrapotassium pyrophosphate (K4P2O7—TKPP), but TKPP use in industrial and institutional liquids is preferred because of its superior solubility and sequestration characteristics. 

Other possible builder salts include sodium trimetaphosphate, trisodium and tripotassium phosphates, and sodium acid pyrophosphate. Each has a unique property whose utility is dependent upon the particular detergent system or application. The book Phosphorus and Its Compounds presents a complete assessment of phosphates and their role in detergents. 

The conventional detergent builders [viz., sodium tripolyphosphate (STPP) and tetra sodium pyrophosphate (TSPP)], have been identified as environmentally unsafe as they cause excessive deposition of phosphates in the water bodies and result in eutrophication. This is a process which causes excessive growth of algae in water bodies, which once died and decomposed, can cause growth of organic... 

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