Morphology Of Y₂O₃Precursor Synthesized Assist By External Field Under Liquid Phase Research On Control Technology

Ultrafine yttrium oxide defects, reunite and low product quality, its application is restricted. Sandyttrium oxide has advantages of large specific surface area, coarse particles and high activity,effectively overcome the ultrafine yttrium oxide used in molten salt electrolysis illiquid, float in the skywhen losses big shortcoming. In this paper, ion adsorption type rare earth concentrate by hydrochloricacid dissolution and extraction separation of rare earth yttrium chloride solution as raw material,ammonium bicarbonate and oxalic acid respectively as a precipitating agent, in a single microwave,microwave and ultrasonic by collaborative mode aided, and through liquid phase precipitation methodprepare super fine and sand yttrium oxide precursor. Study on mole ratio, the initial concentration ofyttrium chloride, precipitant concentration, precipitant drop method, the temperature of the reactionsystem, reaction time, aging time, roasting temperature, roasting time, ultrasonic and microwaveintervention on Y2O3powder particle size and morphology and so on. By using means of techniquessuch as scanning electron microscope (SEM), Thermogravimetric-Derivative ThermogravimetryAnalysis (TG-DTG), X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectrometry tomorphology, particle size, composition and structure of the sample are characterized.The results show that, with NH4HCO3as precipitating agent, in the microwave with ultrasonicmode and under the condition of liquid without modifying agent, yttrium oxide precursor synthesis ofbetter conditions for precipitation methods were：addition, YCl3concentration was0.25mol·L-1,microwave temperature of80℃, reaction time was90min; The needle sub-micron Y2O3precursorwith uniform scatter and the average particle size of about0.26μm was produced. And it is concludedthat microwave drying is superior to the conventional thermal drying. By microwave with ultrasonicsynergy instead of add the effect of dispersant PVP. Yttrium oxide precursor roast1h under600℃after can be obtained high crystallization degree and dispersed yttrium oxide, and yttrium oxidepowders after thermal decomposition is heritable.With oxalic acid as precipitant agent, in a single microwave mode, sandy yttrium oxide precursorsynthesis of better conditions for precipitation methods were：yttrium chloride and oxalic acid molarratio of1:2, YCl3initial concentration is0.5mol·L-1, the reaction temperature of40℃, reaction timeis3h, aging time is8h; D50for about45μm of sandy large particle yttrium oxide precursor can beobtained under the conditions of liquid. Precursor by TG-DTG thermal analysis, when the temperaturerose to about650℃, the TG curve as the horizontal line, decomposition process of precursor basicend; By XRD, cubic yttrium oxide has been initially formed at500℃. When the temperature is900 ℃, the diffraction peak has become very sharp, and the yttrium oxide grain has completedcrystallization, and the grain increase significantly.