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Ferric-Complexed Cyanide (FCC) which was resistant to
destruction by conventional physichemical treatment
technologies was found in various industrial wastes. The
treatment feasibility study was conducted on FCC at high
concentration by using different processes including High
Temperature Hydrolysis (HTH), and Both processes. The
experiments were operated under the following conditions: total
reaction time 150 minutes, mixing rate 1300 rpm and excess air
20%. The reaction temperatures (180℃∼240℃) and hydrolysis
time (0∼150 min.) were selected as the major factors in c
COD, CN, and NH3 were analyzed to evaluate the treatment
feasibility. The results indicated that HTH, WAO and the
combined processes were found effective in the destruction of
FCC at high concentrations. The total cyanide residues showed a
sharp decrease in short time from the start of reaction in all
treatments, and the HTH. In the decomposition of FCC, the HTH
process produced ammonia and formic acid, while WAO yielded
ammonia and carbonate. The results of T-test suggested that the
possible main destruction mechanism of FCC was due to
hydrolysis in the presence of water. Both HTH and WAO processes
in the destruction of FCC appeared to be a first-order two
steps reaction with respect to total cyanide. The activation
energy analyzed by Arrhenius equation was found to be 47229J/
mole for HTH and 54964 J/mole for WAO process in the first
step reaction .
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