Clean

Soap or Detergent?

People often use the terms soap and detergent interchangeably. They both have the same basic function but chemically they are different compounds. Soaps are usually made by processing a fat with an alkali, like sodium or potassium hydroxide, and results in salts of the acids contained in the fat. Detergents are typically made from synthetic substances such as petroleum by-products.

Both soap and detergent act as a surfactant in the cleaning process. The term surfactant is a portmanteau of the words surface acting agent. Surfactants accomplish two things. First, they lower the surface tension of a liquid which allows easier spreading. Used with water in a cleaning application then they essentially “make water wetter”. The second thing a surfactant does is lower the interfacial tension between two liquids. Surfactants have a hydrophilic end (water-loving) and hydrophobic (water-fearing) end. Surfactants work by interacting with water molecules through their water-loving end and other liquids, solids, and gasses through the water-fearing end by forming spherical structures called micelles.

In the case of soap, the water-fearing end is a long hydrocarbon chain called its tail and the water-loving end is a carboxylate head. Oil and grease, which attract dirt, are non-polar molecules insoluble in water. The micelles that form when soap and oil are combined have their tails facing inward surrounding an oil molecule with the heads facing outward held in suspension in the water. Therefore, the grease and oil and the dirt they attract are trapped inside the micelle and can be rinsed away.

Soap is an excellent cleanser but has one attribute that should be understood and counter-acted when used in a cleaning formula. Mineral acids convert the salts of fatty acids in soap into free fatty acids. Free fatty acids are less soluble than the salts of fatty acids – this is what causes soap film – and can be counter-acted with a rinsing agent. Hard water – water rich in magnesium, calcium or iron for example, will cause soap to form insoluble salts. These insoluble salts are what cause “water spots”, bathtub rings and leave our clothes dingy and rough after repeated washings. This can be alleviated by including a water softening agent in cleaning solutions. While synthetic detergents don’t form insoluble precipitates in hard water the use of petroleum by-products in their production makes them a non-choice in my personal cleaning activities.

lemon aide

The citrus limon, or as most of us call it, lemon, is a fruit primarily used for its juice although the pulp and rind are frequently used in culinary applications. Lemon juice is approximately 5% citric acid by volume. It is the citric acid which gives lemons their tart taste and a pH of 2.2.

Citrus fruits also produce an essential oil in glands inside the rind. This oil can be steam distilled and is composed mostly (90%+) of a hydrocarbon classified as a cyclic terpene known as d-limonene. It is a colorless liquid at room temperature and is the substance responsible for the strong citrus smell. You will find lemon oil and orange oil used more commonly in commercial cleaners, strippers and de-greasers as the distillation process requires specialized equipment. You can, however, purchase essential oils of lemon and orange from suppliers of aroma therapy products.

So what makes lemons so great? Lemon juice and lemon oil are an effective, environmentally friendly and relatively *safe solvent that:

1. Will dissolve grease and oil.

2. Dissolves adhesives.

3. Dissolves limescale and hard water spots and tarnish.

4. Will bleach stains on household surfaces and fabrics. It will also bleach your hair and skin.

5. Strips wax and polishes.

6. Will neutralize strong odors.

7. Is an antiseptic and antibacterial effective against candid albicans, e. coli and gram-negative household germs that cause salmonellosis, herpes simplex (types 1 and 2), influenza types A, A/Brazil, A2/Japan, intestinal bacteria, lebsiella pneumoniae, odor-causing bacteria, mold, mildew, salmonella (choleraesuis, typhi, and typhosa), shigella sonnei, staphylococcus aureus, streptococcus (faecalis and pyogenes) and trichophyton mentagrophytes.

8. Is antiviral and will kill the the viral agents of typhoid, gastrotenteritis, rabies, enteric fever, cholera, several forms of meningitis, whooping cough, gonorrhea and some types of dysentery. It is not effective against tetanus, anthrax, polio, rhinovirus, or hepatitis B or C.

9. Will soften hard water and allow soaps and surfactants to be more effective.

10. Can be used as a non-toxic insecticide for house plants or in the garden.

*Citric acid and limonene are skin and mucous membrane irritants. Contact with the eyes can cause a burning sensation. Prolonged exposure of the eyes to high concentrations could cause blindness, as anything with a low enough pH will.

universal solvent

Water is a very strong solvent and often referred to as the universal solvent. A solvent is a liquid or gas that dissolves another substance resulting in a solution. Substances that dissolve in water, like salts, sugars, acids, and alkali are called hydrophilic (water-loving) while those that do not mix well with water, like grease or oil, are called hydrophobic (water-fearing).

Water is, of course, the substance created when two molecules of hydrogen form a chemical bond with one molecule of oxygen – commonly abbreviated as H₂O. Water is a polar molecule. The oxygen has a negative charge while the hydrogen has a positive charge giving the water molecule a strong dipole structure – like a magnet with it’s north and south (positive and negative) poles. And just like a magnet’s poles, a water molecule’s poles are attracted to the opposite charge in other water molecules. This weak interaction causes both water’s cohesive property and adhesion property and is responsible for the high surface tension of water. If you’ve seen water bead up on a surface you’ve seen surface tension. This tension also exhibits another of water’s properties and that is capillary action – or the tendency of water to move upward in a tube against the force of gravity.

Unlike a bar magnet with a single positive and single negative pole the water molecule has two positive poles (the hydrogen atoms) and one negative pole (the oxygen atom) so a U shaped magnet with the bend of the U being the negative pole is a better model. Because magnetic poles attract the opposite charge, if you had 100 water molecules, the negative poles (the oxygen atoms) would be attracted to one of the negative poles (a hydrogen atom) of one of the other 99 water molecules. What about the second hydrogen atom on each of the molecules? They attract other negatively charged molecules. Guess what has a negative charge? Dirt.

Have you ever wondered why fine particles of dirt settle on all the surfaces in your home? Yes, dust is just fine airborne particles of dirt. Well, our planet is constantly bombarded by waves of energy that we can’t see. Besides the UV (ultraviolet) rays that cause sunburn, there are longer wave lengths of energy called Gamma Rays. Unlike UV rays, however, which can be blocked by materials (like a hat) or chemicals (like a sunblock lotion), gamma rays go right through everything – including us. When the gamma rays pass through objects they knock electrons out of the atoms the object is made of. And when atoms lose electrons they become slightly positively charged. Since this occurs constantly, most objects in our homes have an overall positive charge. Along comes a breeze that disperses some fine dirt particles in the air that are negatively charged and – you guessed it – the negatively charged dust is attracted to the positively charged surfaces and sticks there.

So let’s imagine a dirty surface, a counter-top for instance, and think what would happen when we spread some water on the counter. Firstly, the “extra” positive poles (hydrogen atoms) would be repelled by the slight positive charge of the counter-top so that the water molecules would be positioned like a U with both positive poles upward and the negative pole downward. The dirt particles on the counter-top, because they have a slight negative charge would be attracted to the “extra” positive poles at the “top” of the water. The dirt particles have now be separated from the surface of the counter and in effect are being held in suspension by the water. Now we simply wipe away the water and the dirt in solution right along with it. In my humble opinion, water certainly deserves the moniker of universal solvent.

airborne dirt

The next worst offender in the ingress of dirt into our homes are airborne particles and they enter through multiple sources.  First and foremost are open windows.  Unfortunately, it’s the one we can do the least about except to keep them closed.  I love open windows when there is a nice breeze but screens do nothing to keep dirt, dust, pollen or smoke from entering our homes.  So if it’s nice enough to open the windows I just plan on doing a little extra cleaning.  The other sources of airborne dirt we can take steps to mitigate:

• Caulk any cracks around doors and windows and make sure they are properly fitted with weather stripping.  This helps your heating and cooling efficiency as well as keeping dirt out.
• Change your HVAC filter every month, more often if the weather has been particularly dry.  I prefer a permanent washable filter over the disposables for ecological reasons.
• Vacuum inside the heating and air conditioing duct work a couple of times a year.  Check for cracks, holes or any openings that may allow dirt to enter from under the house.  Seal with duct tape.  While you’re under the house why not insulate the duct work to preserve the heat or coolness of the air travelling through it.  You HVAC unit won’t have to work so hard and you’ll save money.
• Make sure your clothes dryer and range hood are properly vented to the outside.
• Always use a splatter cover when cooking with any oils or fats on top of the stove.
• If you smoke . . . consider quitting.  Or at least not smoking inside.  At the very least, only smoke in one room, preferably one with the least amount of fabric (upholstery, carpet, and drapes soak up tar and nicotine and odor like wicks) and get yourself a negative ion generator.  A negative ion generator is a small electric device that spits negative ions out into the air.  The negative ions attach to smoke and dust particles in the air.  The combined weight of the particle with a negative ion makes it drop straight to the floor where it stays until the next time you vacuum.