【Epoch Times News, November 14, 2024】Doing laundry is an essential part of everyday life. When you are choosing between laundry powder and liquid detergent, have you ever thought about the differences between the two? Which one is better? Let’s hear what the experts have to say.
Nathan Kilah, a senior lecturer in chemistry at the University of Tasmania in Australia, wrote an article on The Conversation website explaining that understanding the chemical components of these cleaning products can help you find the answers to the above questions and maximize the effectiveness of washing your clothes within your budget.
The active ingredients in both laundry powder and liquid detergent are surfactants, also known as detergents. These compounds have two different parts in their structure – one part interacts with water (hydrophilic) and the other part interacts with oil (hydrophobic).
This useful characteristic allows surfactants to remove oil and dirt from clothes and suspend them in water to be rinsed away. Surfactants also help create bubbles.
Metal salts dissolved in water can limit the performance of surfactants. For example, hard water containing dissolved calcium and magnesium salts used by people can easily lead to the formation of soap scum (an insoluble precipitate formed by the reaction of metal salts with surfactants), thus reducing washing effectiveness.
Therefore, modern detergents include phosphates, water softeners, and other metal-binding agents to prevent the formation of soap scum. However, phosphates can lead to excessive algae growth in freshwater environments.
Many detergents also contain optical brighteners. These chemicals absorb ultraviolet light and emit blue light, making clothes appear brighter and whiter.
These cleaning products often contain fragrances. While not necessary, fragrances can give the impression of clean clothes.
Although the ingredients that prevent soap scum formation in detergents and detergents are the most important components in laundry powder, they are not the most abundant ones. The main ingredient in laundry powder is salt (such as sodium sulfate), which increases the volume of the powder and prevents clumping.
Another salt commonly added to laundry powder is sodium carbonate, also known as washing soda (a close chemical relative of baking soda). Washing soda helps chemically alter oils and dirt to dissolve in water.
Laundry powder also often contains oxidizing agents, such as sodium percarbonate. This is a stable combination of sodium carbonate and hydrogen peroxide. An additive called tetraacetylethylenediamine can activate sodium percarbonate, producing a mild bleaching effect.
From a chemical perspective, powders have an advantage – their ingredients can be formulated and mixed but kept in separate solid form.
The main ingredient in liquid detergent is water, and other components must be carefully selected. They must remain stable in the bottle and work together during the wash. These include similar ingredients to laundry powder, such as alkaline salts, metal-binding agents, water softeners, and surfactants.
The surfactants in liquid detergent are usually classified as ionic (charged) or non-ionic (uncharged). Non-ionic surfactants can be liquid, making them unsuitable for powder formulations. Non-ionic surfactants effectively suspend oil stains in water without forming soap scum.
Liquid detergent also contains optical brighteners and preservatives, which prevent microbial growth from damaging the mixture.
Using liquid detergent in washing machines can pose a microbial issue. Liquid detergent lacks the mild bleaching agents found in laundry powder, making it easier for mold biofilm to form in washing machines, and bacteria can more easily transfer between clothes.
However, compared to laundry powder, liquid detergent has an advantage. They can be directly added to stains on clothes before putting them in the washing machine to enhance cleaning effectiveness.
Moreover, some detergents also contain enzymes. Enzymes are proteins that can remove specific stains. Chemically speaking, they are catalysts that accelerate chemical reactions.
Kilah emphasized that consumers choose between laundry powder and liquid detergent based on effectiveness, psychology, cost, scent, environmental factors, and convenience.
You can try different products to find the one that best suits your needs, household budget, and environmental considerations. For example, using products with recyclable packaging is environmentally friendly.
Personally, he uses half the recommended amount of laundry powder for washing at 20 degrees Celsius. These pleasantly scented laundry powders come in recyclable cardboard packaging and contain a variety of enzymes and activated bleaching agents.
He stressed that having some knowledge of chemistry can help keep your clothes clean. Although some manufacturers may not disclose a full list of ingredients on their cleaning product packaging, you can find more information on the product’s website.