This is a bit of a pet peeve with me. The conventional wisdom is that PBW is percarbonate based. Other than the Internet echo chamber, I have absolutely no evidence this is true, and some evidence to the contrary. I’m hoping somebody has some convincing evidence, one way or the other.
This is a chemistry question, please no posts on ‘I use this’, ‘this is how I clean’ etc.
From the MSDS:
PRODUCT NAME: PBW
COMPOSITION: SILICATES, PHOSPHATES, AND SURFACTANTS
Sodium Metasilicate (CAS# 006834-92-0) 30%
by comparison, the MSDS for OxiClean
COMPOSITION/INFORMATION ON INGREDIENTS
CAS Number Chemical Ingredients % By Wt.
0497-19-8 Sodium carbonate 50-75%
15630-89-4 Sodium percarbonate 30-45%
68002-97-1 Ethoxylated Alcohol C12-C16 1-3%
68479-09-4 Sodium polycarboxylate 1%
06834-92-0 Sodium metasilicate 1%
I think we can all agree OxiClean really is percarbonate. When I use it to clean bottles, little bubbles form on the bottles. It precipitates calcium carbonate in hard water. It loses it’s effectiveness in a few hours.
None of these things is true of PBW. If I remember correctly, Charlie Talley developed PBW for Coors as an alternative to lye. They were cleaning copper plate chillers and the lye, besides being nasty, was dissolving the copper.
Can we bust this myth, or am I all wet?