CLEANING PRODUCTS:DRAIN CLEANERS.

DRAIN CLEANERS

Drain cleaners/openers are formulated to unclog kitchen sink and bathroom/lavatory drain traps. Most sinks are synthesized of steel coated with enamel, and the drain trap beneath is usually made of brass or polyvinyl chloride. Brass is an alloy consisting mostly of copper (Cu), with a key additional incorporation of zinc (Zn). Although copper is relatively unreactive toward both bases and acids, zinc reacts easily with acids and slowly with bases. When such drains become clogged, it is usually because of the accumulation of greasy/fatty soap scum, hair, and related unwanted products. Thus, the classic key active ingredient in drain cleaners is the caustic alkaline chemical sodium hydroxide (NaOH), also referred to as “lye,” either in solid form with small chips of aluminum or as a concentrated liquid. When added to the product, the aluminum metal reacts with the sodium hydroxide solution to form hydrogen gas (H2), which initiates a bubbling effect within the clog, thereby creating a stirring and agitation action.

Liquid and gel-based drain cleaners marketed for consumer household use can contain a combination of sodium hydroxide, sodium hypochlorite (NaOCl; bleach), sodium silicate (abrasive), and various detergents (surfactant cleaning action). In general, the sodium hydroxide reacts with the water in the pipe to generate a significant amount of heat, which melts away most of the greasy clog. The melted substances are thus bro- ken down into simpler substances that can be rinsed away. A strong alkali will react with fat (e.g., triglycerides) to produce soap plus glycerine. Thus, the sodium hydroxide also reacts with some of the fatty grease, converting it to soap (i.e., saponification), which then is available to assist in cleaning and emulsifying the remainder of the grease within the pipe by a detergent action. If hair is the primary drain-clogging culprit (e.g., in shower drains), the bleaching agent included in the drain cleaner will degrade the keratin protein-based hair strands via oxidation, helping to unclog the drain.

Drains that simply possess slow water drainage, which are not truly blocked/plugged, can often be cleaned with slow-acting drain cleaners formulated with enzymes designed to degrade large insoluble organic (carbon-based) molecules into many smaller, water-soluble molecules. Examples of such enzymes include amylase (which breaks complex starches into glucose monosaccharide units), lipase (which breaks fats into glycerol and fatty acid units), protease (which breaks proteins into amino acid units), and cellulase (which breaks cellulose into glucose monosaccharide units).