The influence of temperature (20–1000 °C) on binary mixtures of solid solutions of CH3COOLi·2H2O–MgHPO4·3H2O

Thermally induced phase transitions (20–1000 °C) in the substrates and binary mixtures of CH3COOLi·2H2O(1)–MgHPO4·3H2O(11) have been analysed. Changes taking place on dehydration and thermal dissociation of binary mixtures prepared with percent molar ratios of 90–10% were studied by differential thermal analysis (TG, DTG, DTA), IR-spectroscopy and WAXS.The above-mentioned substrates changed their structure when heated for 1 h at 500 or 1000 °C. CH3COOLi·2H2O(1) (ID: 23-1171) changed the structure at 500 °C to that of Li2CO3 (ID: 22-1141), while at 1000 °C the structure was impossible to analyse as the compound reacted both with porcelain and with platinum (crucible materials). MgHPO4·3H2O(11) (Newberyite, ID: 35-780, 19-762) changed its structure at 500 °C to amorphous phase and at 1000 °C to Mg2P2O7 (ID: 32-626).The following compounds were assayed in the respective binary mixtures heated at 500 °C for 1 h: 70% (1)–30%(11): LiMgPO4 (ID: 18-735), MgO (ID: 4-829); 50%(1)–50%(11): LiMgPO4 (ID: 18-735), Li3PO4 (ID: 25-1030); 30%(1)–70%(11): LiMgPO4 (ID: 32-574); binary mixtures heated at 1000 °C contained the following compounds: 70%(1)–30%(11): LiMgPO4 (ID: 32-574,18-735), Li3PO4 (ID: 15-760,25-1030), MgO (ID: 4-829); 50%(1)–50%(11): LiMgPO4 (ID: 32-574, 18-735), MgO (ID: 4-829); 30%(1)–70%(11): LiMgPO4 (ID: 18-735, 32-574), Mg2P2O7 (ID: 22-1152, 8-38), Li4SiO4 (37-1472).