by Linda Chambers, Soap Warehouse, www.SoapWarehouse.biz
We all know when a cleaner is or is not working, but we do not always know why. Unfortunately for most, learning why becomes a lesson of trial and error. But understanding the basic science of elements and the pH scale can help you safely figure out what should work before you choose a chemical. Also the ability to explain to a customer what you are using and why separates you from the competition as a true professional with specialized knowledge and training.
The Periodic Table of Elements
Most of the products you use will only come from a small portion of these elements. For example, two similar elements that are used in cleaning chemicals every day are Sodium and Potassium. Both are basic alkaline metal elements and are so close to each other they are like cousins. That is why chemical compounds made with the exact same other elements make almost similar chemicals such as Sodium Hydroxide, NaOH (also known as Caustic soda) and Potassium Hydroxide, KOH, also called pot ash.
Due to Potassium Hydroxide’s properties being highly soluble in water and highly reactive to acids, its ability to molecularly infiltrate, (that is break apart acids) and its corrosive nature, it works faster than Sodium Hydroxide when used at the same percentage in a mixture.
To give you an example of the solubility difference, approximately 121 g of KOH will dissolve into 100 ml of water at room temperature, compared with only 100 g of NaOH in the same 100 ml volume, a 20 percent increase. That is why KOH makes a better cleaner – you can get more of a fasteracting chemical in the same volume. But because Potassium Hydroxide is harder to produce, it costs more. That’s why each year in the US, approximately 100 times more Sodium Hydroxide is made over Potassium Hydroxide.
Now let’s do a quick review of the pH scale, which ranges from zero to 14, with a pH of seven considered neutral, like plain pure water.
The pH scale is a logarithmic scale, meaning each point on the scale is based on a multiplier of 10. Moving either direction from neutral (pH 7) means every number on the pH scale is ten times stronger than the previous number unit. Thus, the strength of the acids and bases increase significantly as you move to the extreme ends of the scale. So when you have two cleaners that are only one unit apart, know that the higher one is not just a little stronger, but 10 times stronger.
For instance if the pH of 7 equals one inch then a pH of 3 or 11, just four units in either direction of neutral, would be equal to 278 yards. And the difference of 7, out to 0 or 14 from neutral would equal 158 miles or 10,000,000 inches! Differencesof only 4 pH are a million times different in strength.
Bases are often used in degreasers and caustic cleaners like concrete, truck wash and drain cleaners, which work great in these products for two reasons. First, strong bases break down organic matter such as proteins and greases. Second, when a strong base (alkaline) is mixed with a fat, it turns the fat into soap through a process called saponification. This means it literally turns the thing we are trying to get rid of into a new agent – soap – that helps us clean.
Sounds great, right? Hang on. You first need to be aware of what you are cleaning to be sure it can handle the pH of the cleaner. For instance, bases of high pH are not recommended when cleaning soft stone surfaces like marble or limestone. You also have to be very careful when working with bases, because they breakdown organic matter – which includes skin, muscle and even bone!
On the lower side of the pH scale are acids, which are used for some very specific cleaning jobs: removing rust stains, calcium deposits, and efflorescence on brick; to etch concrete; to dissolve salts and mineral scale created by hard water; to clean coils; and to clean metal surfaces, such as removing tarnish and cleaning polished aluminum. But they also eat, pit and dissolve some soft metals like chrome, and soft stone like limestone and marble. Strong acids can be the deadliest chemicals you may ever have to deal with and must be treated accordingly.
What’s in Your Water?
Checking for the hardness and the pH of the water you are using to mix your chemicals and rinsing can make a big difference in cleaning results. Every decrease in the pH of the water you are using to make your chemical solutions is also reducing the pH of your mix.
You can easily measure pH with a strip of litmus paper that is easy to buy. When you touch a strip of litmus paper to something, the paper changes color depending on whether the substance is acidic or basic. If the paper turns red, the substance is acidic, and if it turns blue, the substance is basic. There will be a color chart that you use to judge the pH level.
We have had customers call to say that a product is not working or is harming a surface. We have usually been able to track it back to improper dilution rates or the water source that customer is using. If the pH is higher than it should be, it usually turns out to be an increase due to salts and other minerals in the water, or water hardness that is increasing the pH. Adding water softeners can help, but most municipalities are already doing this.
Hardness is hard to measure out in the field. You should be getting a water report mailed to you from your local water agency each year that tells you about your water, the hardness and pH. If not, or if you work in other areas, you can request copies. If you use well water, you especially should test it your self a few times a year.
Hardness is associated with the ability of the water to work with soap. As hardness increases, more soap is needed to achieve the same level of cleaning due to the hardness positive ions, most commonly calcium and magnesium.
If you read the box of a yellow cake mix, you may see a lot of the same things in each one, but some may need you to add eggs, oil and water while others only need water. Unfortunately, with chemical products, the only things that must be listed on a label or a Safety Data Sheet are the hazardous parts. Companies are not required to say what else is in them or how available those ingredients are to the product as a whole.
Some percentage of ingredients you think would be working for cleaning may be tied up or neutralized by some other non disclosed ingredient. So you have a lot less to go on then when shopping for a cake mix in the grocery store. And with some product categories like window cleaners (until the new SDS laws come into effect in 2016), you may never know what is in them since these products usually contain all nonhazardous ingredients.
Now if you are really understood chemistry, you might be able to figure out some items with clues from the specific gravity, odor, or other physical characteristics of the product then deduce what else could be in it. But as of today, here in the US there is no way for you to know. It is all a guessing game. You must go with results you can see to compare them. It is almost like having to judge a cake by its looks, not by it’s taste. Even if you knew every ingredient in each similar product you may not have all the information you need.
As of today there are manufactures and vendors that are getting around things with the current MSDS laws and they know it. Many companies use statements on their MSDS like, “The information contained herein is believed to be accurate,” or “Vendor assumes no responsibility for injury with use.” In others words, buyer and user BEWARE.
I am not saying that companies that use these phrases have something to hide, just that they only know as much as their manufacturer is telling them, which may not be everything, so be careful and hopefully in a few year with new SDS regulations it will get better for the contractor.
Which is best?
A question I am asked a lot is “which brand product (that contain the same ingredients) will work better?” That can be very hard to say. The reason is the same ingredients can have a vast difference in quality, which can make a big difference in results. That will usually show up in the price – but not always.
Take white rice for instance. Do you ever notice that the there can be a wide range in price for plain white rice? There isn’t anything else in that bag, so why the difference between the store value brand, Mahatma or Uncle Ben’s? Price may judge some types of quality – whole grain kernels instead of broken pieces, the cost of proper bleaching methods, a better genetic strain of rice. So too with chemical ingredients. Was it made in a clean facility, not cut with fillers, is the ingredient 100 percent chemically available?
So do not always think the cheapest product will still be able to do the job, and don’t think the highest priced product must work the best. You must do your own evaluation of products. Just be sure you are comparing apples to apples. You must get them to the same level to be able to judge them head to head.
Linda Chambers is the Brand and Sales Manager for Soap Warehouse, where she has worked since 2007. She enjoys writing blogs and social media. She also travels for the company, exhibiting at trade shows and events. For more information, visit their website at www.SoapWarehouse.biz.