supply of heavy chemicals supply of heavy chemicals ( caustic soda flakes and phosphoric acid ) for various sugar factories of sugar coprporation in uttar pradesh for the season 2021-22 - sodium hydroxide ( caustic soda flakes ) . percent by mass minimum purity99.50%. rayon grade conforming to is:252:1991. ( reaffirmed 1996 ) ( rates inclusive of packing & forwarding, transportation, insurance charges ) heavy chemicals ( phosphoric acid ) food grade confirming to is:10508-1983 ( min. purity as h3po4 percent by mass-85%, specific gravity 25° / 25°c-1.71, impurities well within the prescribed limits as is referred above. ( rates inclusive of packing & forwarding, transportation, insurance charges ) floculant color precipitant antifoam