"buffered" cleaning agents and wool

[Dolly Llama]

One of my mentors here posted this and if someone could further explain "buffers" to me, it would be 'presheeated



"[wool]Pretty easy to work with if you follow those rules: Keep the heat down on deep colored or patterned/colored wool carpet for the sake of the dye; a higher pH can be used if it isn’t buffered to retain that high pH. (I believe that a buffered “8” pH product can be cumulatively worse than an unbuffered “10” pH)"

help me understand what the buffering agent is, why it's used and what the drawbacks are.

and if at all possible, explain it in "6th grade chemistry" language ....cause i wasn't in skOOl much starting with 7th grade ....and paid little attention when I did show up... :shock:


..l.T.A.

 

[Shawn Forsythe]

"Buffering" is the characteristic of a substance to resist pH change, when a substance of disparate(different) pH is added to that substance.

A cleaning agent of a certain pH, say 10 pH, might seem to always be something you would not want to be used in any kind of cleaning of wool. However, it must be understood that the soiling present, and sometimes the natural fiber itself will have some reaction with the cleaning agent used.

If the cleaning agent has very low buffering characteristics, the soil and fiber will have no trouble in "adjusting" the pH of the cleaning agent as to be then rendered harmless, as the net pH will be well in the tolerable range of the fiber in seconds.

If on the other hand, a highly buffered cleaning agent, that is slightly outside the tolerable range of the fiber or dye's "comfort zone", the agent will instead alter the pH of the fiber to a state which is harmful to that fiber.


Think in terms of two armies face to face. pH represents the initial strength of those armies (the number of combatants on the front line). The armies will face off. At face value, we might see that one army has 100 soldiers on their front line, while the other army has only 80. Logic says the army with 100 soldiers on the front line has the advantage. However, what we did not test for is how deep those columns are. If the 80 person wide army has a column depth of 100 soldiers, versus the 100 wide army has a depth of only 5, we then see that the 80 wide army will be much more resistant to a change in the number of soldiers on the front line.

pH is only one test of a the relative acidity and alkalinity of a substance. You have to know the whole picture. Concentration, volume and buffering capacity can make a huge difference in how "strong" an acid or an alkali is, and how it might effect fibers and dyes.

 

[Bob Foster]

People have mentioned cleaning problems occurring because of the previous cleaning with a buffered prespray. Can someone comment on that.


Good to see you back posting again Shawn.

 

[Desk Jockey]

Hey Shawn, good to see you posting! 8)

 

[The Great Oz]

Bob, the affect of a buffered residue can be cumulative.

You clean say, a braided or an Oriental rug with a truck mount and your usual juice. Everything looks great, you collect and go on your way. Three years later you clean the rug again, and again everything's fine. At this point you're firmly convinced that worries about pH are scare tactic BS.

The next time you clean it the dyes explode, or worse the first time YOU clean it after multiple cleanings by some other guy. It just took a few chemical applications for the pH to get high enough to make the damage visible.

You won't see felting in hotel carpet that gets thousands of foot steps per day, so why would the traffic area in a residence have a mat of felted fiber at the top of the nap? Someone used a high pH traffic lane cleaner on it and it probably took several months for the felt to develop. The cleaner is long gone and is convinced that there is nothing wrong with using his nuclear juice on wool.

PS: Nice explanation Shawn.

 

[rhyde]

All buffers are not equal "buffer capacity" it's ability to resist pH changes is the issue a buffer with a low capacity but high pH is less harmful than a lower pH with a high capacity.

The soil load in a wet wash system with a dirty wool rug will kick the pH of many cleaning products that are 8-9 pH to to 6-7 often faster than you can test the pH.

 

[J Scott W]

People have mentioned cleaning problems occurring because of the previous cleaning with a buffered prespray. Can someone comment on that.


Good to see you back posting again Shawn.

Although the time a product spend in contact with the carpet fiber during cleaning may only be a few minutes, the residue may remains for many months or even years.

If the product was highly buffered, even a little residue left for a long time has a much greater effect on the dyes and the fiber than a higher pH but non-buffered product would in a few minutes of cleaning.

 

[Kernm1229]

This is a great discussion. A few additional details might be helpful:

1. A previous note reminded us that the purpose of a buffer is to resist pH changes. By using a buffer, then, we have enough reserve alkalinity to attack that one spot on the carpet that has a lot of soil without having to kick up the pH of the overall cleaning solution.

2. Buffers are salts of different kinds. Because they are salts, of course, they will not evaporate. They have to be actively neutralized or thoroughly rinsed. If previous cleanings involved the use of a buffered detergent, and if the neutralization / rinsing process was inadequate, there could be a pretty significant accumulation of buffering salts over time.

3. It's wise to keep the pH paper or pH stick handy. This way you can test and be sure that any given acid rinse was successful. You might have applied the recommended amount of acid rinse;that recommended amount, however, might not have been enough to overcome the buffer that has accumulated in the carpet during previous cleanings.

4. One other interesting detail: sodium bicarbonate (a.k.a. baking soda) is found in a number of home use odor control products and it does a great job. At about 158 F, however, sodium bicarbonate starts converting to sodium carbonate (washing soda). At that point it becomes a much stronger alkali as well as a buffering salt. That temperature is pretty close to the operating temperature of many cleaning operations. So if there is a lot of white powder packed into the backing of the carpet, you might find that the pH of that carpet will be unexpectedly high after extraction. Easy to correct, of course. You just have to be aware that it might be there.

 

[Dolly Llama]

cool beans
I think ...maybe...it's starting to seep thru the cracks in my rather thick skull ....
lemmie see if i have a grasp of this yet....


A buffering agent is used to strengthen/re-enforce a particular cleaning agent's likelihood to loose efficacy on certain soils and/or fibers???

or in other words ...

if a soil and/or fiber is on the acid side, an unbuffered alkaline pre-spray would rapidly lose it alkalinity and become less effective on the soil???

edit ...pee ess...it IS good to see you posting again, Shawn .
the the first part of your explanation helped .
The others added more clarity

the battle analogy didn't help much though..I got distracted thinking how I'd use the addition 20 soldiers to out flank the deeper 80 man column ......


..L.T.A.

 

[Kernm1229]

Don't be so hard on yourself, Larry.

You described it just right - and in far fewer words than I used!

 

[monica]

At one time, it was believed that photographs stored in buffered enclosures might be adversely affected by buffering. . .