Bio-based, PFA-free fire foam concentrate compositions comprising plant proteins, surfactants, alcohols, and builders, production thereof, and use thereof
A PFAS-free fire foam concentrate composition comprising water, a plant-based protein, a surfactant, an alcohol, and a builder. The bio-based content of the PFAS-free fire foam is preferably 80% by weight or greater. There is also disclosed a process to produce the PFAS-free fire foam concentrate composition, and the application of the fire foam concentrate onto a Class A fire or Class B fire.
1 . A method for producing a PFAS-free fire foam concentrate, the method comprising:
mixing water containing 0.1-1 wt % sodium bisulfite or sodium sulfite and a plant protein to form a protein dispersion, wherein the protein dispersion comprises 30 wt % plant protein and has an initial viscosity of greater than 100,000 cps when first dispersed;
adjusting the pH of the protein dispersion to pH 7-8 by adding a mixture of sodium carbonate and sodium bicarbonate;
after adjusting the pH, modifying the plant protein in the protein dispersion through a chemical reaction using an alcalase protease enzyme at a temperature between 30 degrees C. and 50 degrees C. for a reaction time of 1-2 hours to reduce the molecular weight and dispersion viscosity of the protein dispersion to less than 2000 cps utilizing spindle 4 at 100 rpm at 40° C.;
adding 1-biobutanol to the protein dispersion to halt the chemical reaction triggered by the introduction of the enzyme;
combining the modified protein dispersion with a surfactant mixture comprising cocamidopropyl betaine (CAPB) and sodium lauryl sulfate (SLS); and
adding citric acid as a builder to form the PFAS-free fire foam concentrate having a bio-based content of greater than 80% on a dry weight basis and comprising from about 50% to about 70% of plant protein based on the total dry weight of the concentrate.
2 . The method of claim 1 , wherein the plant protein comprises a soy-based protein.
3 . The method of claim 2 , wherein the soy-based protein comprises soy flour.
4 . The method of claim 1 , further comprising adding a bio-based surfactant or bio-based surfactant mixture to the protein dispersion.
5 . The method of claim 4 , wherein the bio-based surfactant is derived from a plant oil selected from the group consisting of soy oil, linseed oil, flaxseed oil, cottonseed oil, canola oil, sunflower oil, peanut oil, lupin oil, palm kernel oil, and coconut oil.
6 . The method of claim 1 , further comprising diluting the PFAS-free fire foam concentrate with water to form a diluted wetting agent for fire suppression.