Patent Number: 046612912
Section: abstract

According to the method of this invention for fixation of incinerator ash, incinerator ash containing SiO.sub.2 and Al.sub.2 O.sub.3 is incorporated with NaOH or NaOH and an SiO.sub.2 -containing substance in such an amount that the resulting mixture contains 25 to 90 wt % of SiO.sub.2, 2 to 10 wt % of Na.sub.2 O, and more than 3 wt % of Al.sub.2 O.sub.3 which is less than the content of SiO.sub.2 in terms of mol %; 100 parts by weight of the mixture is mixed with more than 5 parts by weight of water; and the resulting mixture is subjected to hydrothermal reaction under a pressure of 70 kg/cm.sup.2 or above and at a temperature of 150.degree. C. and above, whereby the fixation is accomplished.. According to the method of this invention for fixation of iodine sorbent, iodine is allowed to be adsorbed on a silver-loaded silicate sorbent; the iodine sorbent is mixed with 1 to 30 wt % of at least one of sodium hydroxide, potassium hydroxide, and barium hydroxide; and the resulting mixture is subjected to hydrothermal reaction under a pressure of 70 kg/cm.sup.2 and above and at a temperature of 150.degree. C. and above, whereby the fixation is accomplished.