... triphenylphosphine (TPP), caprolactam, asphalt and other organic chemical products; and sodium sulfide, ion-exchange membrane ... ) caustic soda, potassium hydroxide, chromic anhydride, sodium hydrosulfide, calcium chloride dihydrate , sulfur, phosphorus ... disodium hydrogen phosphate, sodium phosphate, magnesium chloride, sodium sulfate, sulfonate, alkali metal carbonate, sodium and other minerals ...