水热刚玉微粉合成过程压力、温度与保温时间的优化

在Al2O3—H2O相态图确定的理论温度和压力基础上，根据水热刚玉微粉实际合成过程中反应物成分、原料粒度以及加热均匀性等影响因素，研究了反应压力、温度和保温时间参数对微粉粒径尺寸和颗粒形状的影响，以进一步优选最佳(压力)P—(时间)T关系曲线，通过不同的(时间)T—(压力)P—(温度)t关系的试验，最后，可得到与预期理想产物相符的T-P-t曲线。结果表明：在矿化剂、原料、温度、保温时间保持稳定条件下，压力越大，产品粒径越粗，结晶越完整，产品转化率越高；而在矿化剂、原料、压力、温度保持稳定条件下，保温时间越长，产品粒径越粗，α-Al2O3转化率也越高；但同等条件下保温时间对粒度的影响不如压力的影响大。

OPTIMIZATION OF PRESSURE,TEMPERATURE AND INSULATION TIME OF THE SYNTHESIS PROCESS OF HYDROTHERMAL CORUNDUM

Based on the theoretical temperature and pressure as determined by the Al 2O 3-H 2O phase state diagram, and considering the influencing factors of hydrothermal corundum such as the reaction materials' compositions, grit sizes and heating evenness, this paper studied how reaction pressure (P), temperature(t) and insulation time (T) affect the grain sizes and shapes of micropowder so as to optimize the P-T relation curve By making experiments on different T-P-t relations, a T-P-t curve can be found in accordance with expected ideal product The results showed that, if the mineralizer, raw materials, temperature and insulation time are stable, the higher the pressure is, the larger the grains will become, and the crystallization will be more complete and the conversion rate will be higher; if the mineralizer, raw materials, pressure and temperature are stable, the longer the insulation time is, the larger the grains will become, the conversion rate of Al 2O 3 will also be higher; if the synthesis conditions are kept the same, the influence of insulation time on grain size is not as strong as that of pressure