Chemical Drain Cleaner
History Drain Cleaner
Danger and Usage Considerations for Drain Cleaner
Handheld Drain Auger
Air burst Drain Cleaner
Home Remedy Drain Cleaners
Hydro-Mechanical Drain Cleaners
Electric Drain Cleaner
Drain Cleaner Water Jetters
Drain cleaners were developed alongside the drainage systems that became more widespread and common within the 20th century. Due to this, the history of cleaners in America is not well documented until the early 20th century when more American homes did begin to feature these systems. Before this, unwanted waste and water was often collected in basins after it had been used and was then disposed of. Lead was originally used to develop piping systems, but lead was discovered to be poisonous, after World War I, and so the systems were refurbished with galvanised iron.
Galvanised iron is actually steel encased in zinc, to protect it, but this was later adapted when it was realised that zinc can be affected and may corrode when exposed to the elements. The zinc corroding occurred down to the base material and so rust was formed. This then led to the drains becoming blocked due to a build-up of deposits which inspired the creation of drain cleaners.
Due to the corrosion that occurred on iron pipes, copper and plastics (PVC) were used to replace the original pipes by the 1960s. These new pipes did not contain zinc and so would not decay or expose the base metal. Materials like hair and oils still proved to be a problem as they still blocked the newer pipes. This was a catalyst for the creation of chemical drain cleaners which could eliminate these materials.
Chemical, alkaline drain cleaners predominantly contain sodium hydroxide (lye), which allows for it to dissolve heavier oils and hair. Potassium hydroxide is also used as a secondary ingredient for alkaline cleaners and these can be purchased as either a liquid or a solid.
Solid variants of the alkaline drain cleaner contain a caustic material (usually potassium hydroxide or sodium hydroxide), additives and aluminium particles. These additives usually contain wetting agents, like alkyl aryl sultanates, but the precise elements included in commercial drain cleaners are unknown as the combinations are different and specific to particular brands.
The aluminium particles, that are present in solid caustic drain cleaners, is an aluminium oxide which disintegrates and re-oxidises and produces gas (hydrogen.) The hydrogen released is an exothermic reaction and residual heat is also produced during this reaction. This heat then helps to break down the oils and hairs that may be blocking the drain. This reaction can be seen below.
Breakdown of aluminium oxide: AI203 + 2NaOH + 3H2O → 2Na[AI(OH)4]
Oxidation of aluminium metal: 2Al + 2NaOH + 6H2O → 2Na[Al(OH)4] + 3H2
The actual removal of the substance blocking the drain occurs when the substance reacts with the hydroxide ions (-OH) which are created by the drain cleaner. These substances blocking the drain are often natural ones like hair and oils and so are broken down via a saponification reaction of triglyceride and a base. Lye dissolves in the water and hydroxide ions are produced. These then attach the carbonyl carbons of the fat and this begins the hydrophobic tails of the triglyceride (e.g glyceryl trifoliate) to separate glycerol and a fatty, acidic salt.
Drain cleaners that can eradicate hair and oils (alkaline cleaners), do so via alkaline hydrolysis of amide and ester functionalities, as shown below.
RCONH2 (amide or protein) + OH− → NH3 + RCOO−
RCO2R’ (ester or fats) + OH− → R’OH + RCOO−
Due to solid lye being hygroscopic, it is imperative that the drain cleaner is placed directly next to the substance blocking the drain. This is to ensure that the lye doesn’t absorb the water going through the pipes, expand and then increase the size of the blockage, therefore making the problem worse.
Liquid alternatives of drain cleaner often include sodium hypochlorite (more commonly known as bleach) and lye (sodium hydroxide or potassium hydroxide) in concentrations of upwards of 50%. Alternative corroding solutions may initially come in separate parts which are mixed as they are poured into the drain. Within the drain, the two solutions mix together, form a gas and surfactants confine the gas by solidifying it as a thick foam. This foam is used to coat the interior of the pipe and the materials forming the blockage are then displaced. Liquid alkaline drain cleaners are heavier than water, as they are a base which is then dissolved in water, and so the formular can descend to the origin of the blockage.
Drain cleaners that contain high concentrations of sulphuric acid are known as acidic drain cleaners. These can disintegrate blockages formed by substances like cellulose and proteins like hair. They can also remove fats via hydrolysis.
Companies that produce acidic drain cleaners do list some potential hazards that may occur from their use. Some of these hazards include: an aggressive reaction with water, the creation of a combustible hydrogen gas upon interaction with the majority of metals, immediate or long-lasting health hazards if inhaled or ingested, and can cause serious burns to the flesh. If this substance comes into contact with eyes, it can potentially result in permanent blindness and can corrode any human tissue. The substance can also be fatal if it is swallowed. The reaction caused by these drain cleaners is so drastic that the drain cleaner must be added into the drain very slowly to minimise any potential hazards.
High concentrations of acidic drain cleaners hydrolyse fats and proteins (like hair) via acid hydrolysis. This is a similar process to the one caused by alkaline cleaners, but the reaction with acidic cleaners can be seen below.
RCONH2(amide or proteins) + H3O+ → NH4+ + RCOOH
RCO2R'(ester or fats) + H2O + H2SO4 → RCO2H + R’OH
High concentrations of sulphuric acid dehydrate materials that contain carbohydrates (for example, tissue paper which is made from cellulose:)
(C6H10O5)n + H2SO4 → 6n C + 5n H2O