Europium oxide (Eu2O3) is used in the manufacture of fluorescent materials, laser materials, X-ray sensitized screen activators, and stimulated emission phosphors for new X-ray medical diagnostic systems. It can also be used to make colored lenses and optical filters, for magnetic bubble storage devices, control materials for atomic reactors, shielding materials and structural materials. Europium absorbs more neutrons than other elements, is used as neutron absorbing material in atomic reactors, and is used as raw material for the synthesis of other europium compounds. With the development of science and technology, europium oxide will show its importance in the field of special-purpose materials.
The preparation of rare earth oxides is usually carried out by liquid phase precipitation, which mainly includes oxalate precipitation, ammonium bicarbonate precipitation, urea hydrolysis and ammonia precipitation. Europium oxide is prepared by oxalate precipitation and ammonium bicarbonate precipitation. In general, oxalate precipitation method is to add solid oxalate or solution to europium solution at a certain temperature and get europium oxide after aging, washing and burning. Oxalate precipitation method has the advantages of good crystal shape of sediments and easy filtration, etc. However, oxalate price is high and the precipitate mother liquor is acidic, which needs further treatment. Ammonium bicarbonate precipitation is generally under a certain temperature will join the europium solution, ammonium bicarbonate, or solid solution, washing, burning get europium oxide by Chen, has low cost and process stability are good, but the law of precipitation wastewater containing high concentration of NH4Cl, not emissions, if direct emissions, can cause the pollution of water body, be badly in need of the development of new low-cost non-polluting precipitation process. In addition, the current production technology of Europium oxide (Eu2O3) is mainly extracted by reduction extraction method, and the solution of europium chloride or europium nitrate is obtained, and then the solution of europium oxide (Eu2O3) is prepared by precipitation and burning.
The present invention aims to provide a method for preparing europium oxide with plant precipitant. The process is simple, easy to operate, high quality, low cost, precipitation wastewater does not contain ammonia nitrogen, will not cause water pollution, green environmental protection, good crystal precipitation, easy to filter and wash, burning after the europium oxide product purity is high, suitable for large-scale industrial production.
To achieve the above purposes, the technical scheme provided by the invention is as follows:
First, the invention provides a method for preparing europium oxide with plant precipitator, including the following steps: S1: Heat europium solution, then add plant precipitator to get a mixed reaction system; White crystal precipitation was obtained by adjusting the pH value of the mixed reaction system to 6 ~ 8. S2: The white crystal precipitation and the mother liquor were allowed to stand and age, and the white precipitation after standing aging was filtered, washed and burned to obtain europium oxide.
Preferably, the europium solution in S1 is an inorganic salt solution of europium, and the inorganic salt solution preferably includes one or more of the chloride solutions, nitric acid solutions and sulfuric acid solutions of europium.
The concentration of europium solution was calculated as REO, 0.2 ~ 1.5mol/L.
In S1: The heating temperature is 40℃ ~ 100℃, and the mass ratio of plant precipitator and solute (as REO) in europium solution is (5 ~ 50) : 1.
S2: The static aging time was 0.5 ~ 72h, the burning temperature was 850℃ ~ 1100℃, and the burning time was 1 ~ 12h.
Preferably, S2 also includes the following steps: discharge the filtered mother liquor directly or recycle it.
In the second aspect, europium oxide is prepared by the method provided by the present invention.
Compared with the existing technology, the technical scheme of the invention has the following advantages:
(1) The invention uses plant precipitator to prepare Europium oxide. The process is simple, the operation is convenient, the quality is high, the cost is low, the precipitation wastewater does not contain ammonia nitrogen, will not cause water pollution, green environmental protection, and the precipitation crystal shape is good, easy to filter and wash, after burning the product of europium oxide has high purity, suitable for large-scale industrial production.
(2) The invention uses plant precipitator to prepare europium oxide, the yield of the product is greater than 98.5%, and the concentration of NH4+ in the precipitated mother liquor is lower than 2mg/L. In addition, the precipitation obtained in the preparation process of the invention is easy to be filtered and washed and is suitable for large-scale industrial production.
(3) the present invention USES europium oxide precipitating agent preparation plants, plant precipitant including herbs and the precipitating agent made of herbs, can replace the current process using ammonium bicarbonate, oxalic acid and other chemical raw materials, and does not produce or acid wastewater containing ammonia nitrogen, not cause of eutrophication pollution, oxide in lower production cost but also can effectively solve the problem of production process of waste water discharge.
24
Dec
