| 摘要 |
<p>HCl mfr. involves reaction of CaCl2 with a molar excess SiO2, having a surface area of >=15m2/g, at >=600(1000) degrees C in the presence of steam. Pyrohydrolysis of CaCl2 can be effected faster or at a lower temp. than in the presence of ground quartz. The process is useful for the prodn. of HCl from waste materials, without high energy consumption, and also yields alpha-CaSiO3 in very porous form, which is useful for thermal insulation up to its m.pt. (ca. 1500 degrees C). The CaCl2:SiO2 molar ratio is 0.25-0.90. The mixt. pref. is briquetted and reacted in a stream of steam in a fluidised bed reactor.</p> |
