Bleach is a common household chemical used to remove stains, disinfect, and deodorize. Two of the most common types of bleach are chlorine bleach (e.g., Clorox) and oxygen bleach (e.g., peroxide, Oxiclean). Here is a look at the difference between chlorine bleach and oxygen bleach, the pros and cons for each chemical, and which type of bleach is best to use.
What Is Bleach?
In general, a bleach is any chemical that decolorizes and removes stains from fibers, fabric, and surfaces. Because of the way they work, bleaches also kill algae, bacteria, and viruses. Some types of bleach also remove odors.
The way bleach works is by breaking chemical bonds in organic molecules. When bonds are broken in pigmented molecules, the molecules can’t absorb light, rendering them colorless. The process changes the molecules so they may lose their ability to bind receptors in the nose, so they lose their odor. Breaking bonds makes algae unable to perform photosynthesis and denatures proteins in bacteria and viruses.
There are two broad categories of bleaches. An oxidizing bleach uses the chemical reaction called oxidation to break the chemical bonds in the colored parts of molecules (the chromophore). A reducing bleach uses the reaction of reduction to change double bonds into single bonds, which also disrupts chromophores.
Oxygen Bleach and Chlorine Bleach Similarities
Both chlorine bleach and oxygen bleach are oxidizing bleaches. They share some similarities:
- Both types of bleach remove stains.
- Both types of bleach are excellent disinfectants.
- Both work best in hot water, but function in cool and warm water.
- Both have shelf lives of several months, although chlorine bleach typically remains active longer than oxygen bleach.
Differences Between Chlorine Bleach and Oxygen Bleach
But, there are significant differences between the two types of bleach:
The active agent in chlorine bleaches is chlorine, usually as hypochlorite (e.g., sodium hypochlorite, NaClO). Chlorine gas and chloramine also act as chlorine bleaches. The active agent in oxygen bleach is oxygen, usually as a peroxide compound, such as hydrogen peroxide (H2O2). Other oxygen bleaches include sodium percarbonate (Na2H3CO6), sodium percarbonate (Na2H4B2O8), ozone (O3), benzoyl peroxide [C6H5COO)2], potassium persulfate (K2S2O8), and peroxoacetic acid [H3CC(O)OOH].
You don’t want to handle or drink either oxygen bleach or chlorine bleach. However, diluted oxygen bleach is usually safe enough to touch, providing you rinse it off. Chlorine bleach is toxic, poses a splash risk to skin and eyes, and evolves toxic fumes.
Oxygen bleach is considered to be more eco-friendly because it’s biodegradable and safe for septic systems. However, household chlorine bleach actually is safe for the environment. It disappears almost immediately in water and soil. The concern is that it releases volatile chlorine species into the air. These chemicals are toxic and suspected human carcinogens. Using chlorine bleach indoors poses a health risk.
Chlorine bleach should not be mixed with any other cleaners unless they are made to work with bleach. It releases dangerous fumes when mixed with ammonia, acetone, alcohol, vinegar, and other chemicals. Oxygen bleach plays well with most other cleaners, but it should not be mixed with vinegar.
Effects on Fabric
Chlorine bleach damages fibers and fabrics. The damage is irreversible and cumulative. It’s more powerful than oxygen bleach, so it decolorizes prints and dyes and not just stains.
Oxygen bleach is gentler to fibers and fabrics. It can be used on delicate fabrics, such as silk and wool. It’s reasonably safe for colored fabrics, although it may fade them over time.
Chlorine bleach deodorizes, while oxygen bleach does not. However, chlorine bleach also leaves a “chlorine” odor.
Both types of bleach work best in hot water, but oxygen bleach is quite a bit less effective than chlorine bleach in warm or cold water.
Which Type of Bleach Is Better?
Oxygen bleach is the hands-down winner for everyday laundry and cleaning surfaces because it’s less toxic, gentle to fabrics, and safe for colors. However, chlorine bleach still has its place. It’s stronger, works well in cooler temperatures, and deodorizes.
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