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Drano

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Drāno (also spelled Draino or Drano if the ā character is not available) is a drain cleaner product manufactured by S. C. Johnson & Son.


Crystal Drāno

According to the National Institutes of Health's Household Products Database, the crystal form is composed of sodium hydroxide, sodium nitrate, sodium chloride, and aluminum.

The power crystals are simply colored salt, and are the least powerful ingredient. The crystallized lye reacts with fats to form soap. The machined shards of aluminum react with the lye to generate near-boiling temperatures. The sharp shards in the hot churning lye physically cut hair and dislodge deposits. Several chemical reactions take place here:

  1. When Drāno is added to water, the sodium hydroxide, sodium nitrate, and sodium chloride dissolve. The heat of solution liberated when sodium hydroxide is dissolved warms the mixture.
  2. In solution, sodium hydroxide reacts with aluminum to liberate nascent hydrogen, which is a powerful reducing agent. This reaction is exothermic and the heat can cause the mixture to boil. The formula is 6NaOH + 2Al → 3H2 + 2Na3AlO3.
  3. The nascent hydrogen reduces nitrate ion to ammonia, removing the fire and explosion hazard posed by free hydrogen gas. The reaction is: 2NO3 + 9H2 → 2NH3 + 6H2O. The water and sodium ions then regenerate sodium hydroxide and nascent hydrogen.

Crystal Drāno was invented in 1923 by Harry Drackett. Even as Drackett grew to offering over a hundred household cleaning products in the late 20th century, Windex (introduced a decade later) and Drāno provided the lion's share of revenue and profits. Bristol-Myers bought the Drackett Company in 1965 and sold it to S.C. Johnson in 1992.

For years, Drackett advertised Once every week, Drāno in every drain.[1] As many clogs form where a bacterial matrix has been established, the disinfectant action of the hot lye may prevent clog formation. Various mixes of relatively non-toxic solvents are now sold commercially for the purpose. To a certain extent (see Sterilization), even dumping a gallon of scalding water down the drain, however, would have a similarly salutary result with substantially less risk to the environment and at much lesser expense.

Other Drāno products

Drāno Aerosol Plunger was developed in the late 1960s, intended as a safer product that would be kinder environmentally. It was basically just a can of CFC propellant, the best-known brand of which was Freon. After Earth Day in 1970, there came increasing pressure to eliminate CFC propellants. Drackett used cheaper propellants, a blend of propane and butane, in all its other products. However, the propellant mix created a fire hazard.

The product was problematic. The forceful propellant required most consumers use both hands to control the can, plus another hand or two to hold a rag over the drain vent to contain the pressure. The pressure sometimes knocked apart poor plumbing without blasting free the clog. Consumers who ignored instructions and attempted to use chemical drain openers first could be chemically burned from blow-back. The aerosol product was only useful against complete clogs, not against slow drains.

Liquid Drāno was introduced in response to Clorox's purchase of Liquid-Plumr in 1969. Originally, it was simply a liquid lye (sodium hydroxide) but that product proved ineffective and unpopular with consumers. In the late 1970s, the product was reformulated as a combination of liquid lye and sodium hypochlorite. Sodium hypochlorite is sold in 5% concentration as laundry bleach and in 10% concentration as a swimming pool disinfectant.

Foam and gel products have been introduced in recent years, marketed more for slow drains than for opening clogged drains.

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See also