Although the current use of holmium and erbium is still limited, some are equal to people’s further development, but it is certain that, with the development of science and technology, the application of holmium and erbium will be more and more widely, more and more people’s attention. At present, an important reason restricting the application of holmium and erbium is that it is very difficult to separate and purify the holmium and erbium, and the purification process is complex and the cost is very high. For example, baotou steel rare earth research institute adopts high temperature and high vacuum distillation purification technology to develop high purity metal holmium Ho/∑RE > 99.9% with very low non-rare earth impurity content. This kind of process is very complex, high cost, at present only can be applied to the research and experimental stage, if used for industrial applications, is not realistic.
Invented to solve the technical problems in technical solution is a, will contain holmium (Ho), erbium (Er) of rare earth materials into acidic aqueous solution a loop into to the first extraction tank, with P507 (isooctyl phosphonic acid single diisooctyl) mixture extraction agent mixed with kerosene organic phase B, and in contrast to the water phase a pass into the direction of the loop into the first extraction tank, in the water phase and organic phase B a good contact with slot using blender mixing, get Ho, Y, Er and rarely content of rare earth elements (refers to the periodic table) before ion water phase A1, The organic phase B1 containing Ho, Y, Er and subsequent rare earth ions was also obtained. B. The aqueous phase A1 and the organic phase B1 were circulated into the second extraction tank in opposite entry direction. The trough segment where A1 and B1 were fully in contact was stirred with an agitator to separate the rare earth elements before Ho and after Er, and finally the mixed rare earth solution C containing Ho, Y and Er ions was obtained. C, prepare and pre-balance solution C; D, use naphthenic acid, octyl alcohol mixture extraction agent mixed with kerosene organic phase X, will through the c stage of solution in the form of aqueous phase and organic phase c X access in the opposite direction loop into the third extraction tank, c and X full contact slot using blender mixing, separated off Y elements, organic phase at the exit by reverse extraction from mixed rare earth solution containing Ho, Er ion water phase d; E. The aqueous phase D and the organic phase B2 were circularly pumped into the fourth extraction tank in the opposite direction of entry. The tank section where D and B2 were fully in contact was stirred with a blender to separate Ho and Er. The organic phase was backextracted Er ionic solution at the exit and Ho ionic solution was obtained from the remaining aqueous phase. F. Add oxalic acid into the Er and Ho ionic solutions to obtain the precipitate, and burn the precipitate to obtain holmium oxide and erbium oxide respectively.
According to the above method, the first, second, third and fourth extraction tanks are all composed of mixing chamber, submergence chamber and clarification chamber.
According to the above method, the volume ratio of each component in the extractant organic phase B1 and B2 is P507∶ kerosene = 1∶(1-2). The saponification rate is 25% to 40%.
According to the above method, the volume ratio of each component in the extractant organic phase X is naphthenic acid: octanol: kerosene = 22: (16-18) : (60-62); The saponification rate is 75-85%.
The saponification agent for the organic phase of the extractant uses NaOH, and the saponification concentration of B1 and B2 is 0.3-0.6mol/ L and X is 0.45-0.51mol/ L.
According to the above method, all extraction tanks are acidic medium.
According to the above method, the preparation of C solution in stage C is to make the PH value of the solution be 3-4, the concentration be 1-1.5mol/ L, and the layering time after pre-equilibrium shall not exceed 5 minutes.
According to the foregoing method, the burning temperature in the F phase is 800-950℃.
Beneficial effects of the present invention is that the present invention after separation and purification of raw materials can be of yttrium oxide of rare-earth residue or other rich HoEr residue, the applicability is wide and for raw materials of the present invention holmium oxide, erbium oxide of high purity can reach more than 99.95%, and because of the material liquid circulation ventilation with high yield, low consumption, easy operation, continuous production, can also with other process, such as the purification of yttrium oxide and other rare earth oxides adjacent matching, economic benefit is obvious.
The aqueous phase A1 and the organic phase B1 were circulated into the second extraction tank in the opposite entry direction. The mixing chamber, where A1 and B1 fully contacted, was stirred with an agitator to separate the rare earth elements before Ho and the rare earth elements after Er, such as Tb, Dy, Tm, Yb, etc. Finally, the mixed rare earth solution C containing Ho, Y, and Er ions was obtained.
The solution C was prepared and hydrochloric acid was added to make the PH value 3 and the concentration 1.5mol/ L. After pre-equilibrium, the layering time was 3 minutes.
The aqueous phase of solution C was cycled into the third extraction tank in the opposite direction from the organic phase X, and the Y element was separated. The aqueous phase D containing Ho and Er ions in the mixed rare earth solution was obtained by the reverse extraction of the organic phase at the exit.
The aqueous phase D and the organic phase B2 were circularly pumped into the fourth extraction tank in opposite inlet direction, and Ho and Er were separated. The organic phase was backextracted to obtain the Er ionic solution at the exit, and the Ho ionic solution was obtained in the remaining aqueous phase.
Erbium oxalate and holmium oxalate were obtained by adding oxalic acid into the Er and Ho ionic solutions respectively. Erbium oxalate and holmium oxalate were centrifugally dried and placed into a Muff furnace for burning at 900℃ to obtain the products, respectively.