Thermal investigations of CoAPO materials prepared by using piperidine as a structure-directing agent

Two CoAPO materials (CoAPO-34 and CoAPO-20) with relatively high Co2+/Al3substitution level were synthesised in either fluoride-free or fluoride-con taining reaction mixture using piperidine as a structure-directing agent. P resent investigation established that fluoride ions acted only as a mineral ising agent and did not impart any structure-directing role. TG-DTG-DSCcurv es differ considerably for CoAPO-34 and CoAPQ-20, thus indicating that ther mal decomposition of piperidine proceeds in a different manner for these pr oducts. (C) 2000 Elsevier Science B.V. All rights reserved.