The synthesis and properties of high pure δ layered sodium disilicate

delta layered sodium disilicate (delta-Na2Si2O5) is a single layer silicate and has good properties as detergent builder. However, it is difficult to synthesize high pure delta-Na2Si2O5. In this paper, a feasible and simple technology was found by decreasing Na content in liquid sodium silicate (water glass). The crystalline time was short and no seed needed. The suitable synthesis conditions were Si/Na = 1.05 - 1.10, calcining at 720 degrees C for 5 minutes. The synthesis conditions are of industrial value. XRD and Si-29 NIVIR data proved that synthesized samples were delta-Na2Si2O5 without impure phase. High pure delta-Na2Si2O5 exhibited good ions binding ability and reached 312 to 338 mg CaCO3/g.