Facile Synthesis of Zinc-Containing Mesoporous Silicate from Iron Tailings and Enhanced Fire Retardancy of Rigid Polyurethane Foam

Iron tailings (ITS), as solid decay absolved afterward beneficiation, are adverse to the environment. ITS to prepare zinc-containing mesoporous silicate (MAO-Zn) by a calcination-crystallization method are used. An admixture of ammonium polyphosphate (APP) and MAO-Zn can solve the problem of poor flame retardancy in rigid polyurethane foam (RPUF), giving them higher thermal stability and lower heat release. The total heat release rate and smoke factor values exhibited by RPUF-3 are 24.52 MJ m(-2) and 234.29 MW m(-2) respectively, a decrease of 38.45% and 29.60% respectively compared to pure RPUF. Lower combustible and toxic gas release intensities are in RPUF-3. Meanwhile, RPUF-3 possesses enhanced compactness char residue with higher graphitization degree, endowing RPUF-3 with excellent fire observed performance. This work demonstrates the potential of ITS in the fire retardancy field.