| 摘要 |
<p>Sodium silicate for industrial use has the formula 2Na2O.SiO2.8H2O, m.pt. 69 degrees C, solubility in water at 20 degrees C of 288 gpl. density 1.84 at 20 degrees C, and an X-ray diffraction pattern corresp. to a pure cpd. The cpd. is prepd. by heating a sodium silicate (SiO2 : Na2O ratio between 1 and 4) and caustic soda lye for 30 mins at 120-140 degrees C, cooled to a temp. above the cpd. m.pt. when congruent crystallisation is effected. The product is non-corrosive and possesses excellent saponification and emulsifying properties, suitable for degreasing thin metal sheet.</p> |
