Trace Additives to Inhibit the Caking of Purple K for 3-D Firefighting
Abstract
The use of crystal-habit modifying additives was evaluated to inhibit the caking of Purple K dry chemical fire suppression agent. Potassium bicarbonate (KHCO3), which is the active ingredient (>99%) of Purple K, was used as the baseline compound. Micron-sized KHCO3 powder containing additives were produced by a spray and drying technique. However, the quantity of sample produced was insufficient to conduct drop tests. A follow-up effort focused on producing salt cakes with six additives. Cakes were made by spraying 1 ml aqueous solution containing 0.0333 g of corresponding additives onto 30 g of KHCO3 powder, followed by baking in an oven at 60 degrees C for 16 hours. The cakes containing NH4Cl, (NH4)4Ce(SO4)4, and K4Fe(CN)6 displayed improved scattering by dropping from a height of 18 inches, suggesting these additives may have weakened inter-crystalline bridges between the salt particles. These results warrant further tests, in terms of other additives, combination of additives, and additive concentration dependence, to fully assess the effect of crystal habit modifiers on the caking behavior of KHCO3.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2004
- Accession Number
- ADA431168
Entities
People
- Doug Dierdorf
- Eric Proudfoot
- Lixiong Li
- Shawn Hunter
Organizations
- Applied Research Associates (United States)