raw ash and 1.0 mol L1 of alkali solution without seed addition.
During the investigation with encased PTFE reactors (reactor A),
the autogenous pressure of the system reached a maximum of
3.24 104 Pa. At this pressure polymeric PFA reactors (reactor B)
can be used without metal shielding, but equipped with safety
valves. In addition to being low cost, B reactors display heat
exchange differences and are transparent, enabling the reaction
to be visually monitored. Under optimized synthesis conditions,
the yield of reactor B (77%, Test 14) was 17% higher than that of
reactor A (Test 7). In light of the good results, the effect of a shorter
reaction time (from 24 to 16 h) on the formation of zeolite Na-P1
was assessed. A significant decline was observed in zeolite
production (63%, Test 15), albeit higher than that obtained with
the steel reactor over longer reaction times, these syntheses were
done in replicates and the variation of conversion of coal fly ash