38 results about "Inorganic Synthesis Techniques" patented technology

The invention relates to a surface disposal method of an ultraviolet excitation red fluorescent powder, belonging to the field of inorganic synthesis technique of optical function material. The method comprises the steps as follows: the surfactant raw material is screened by a screen of 400 meshes and ball-grinded; subsequently, the consistency of the solution is adjusted and the solution is mixed to gain the surfactant; subsequently, according to the mass percentage in occupation to yttrium europium oxide, 0.005-0.05 percent of surfactant is added into the red fluorescent powder of the yttrium europium oxide; under a mixing state, the surfactant and the red fluorescent powder of the yttrium europium oxide are mixed; the mixture is dehydrated, dried and screened, thus gaining the red fluorescent powder of the yttrium europium oxide with the surface disposed, wherein, according to the mass percentage, the surfactant is one of 5-20 percent Gama-Al2O3 solution, yttrium oxide, potassium silicate, zinc silicate or zinc sulfate. The surface disposal method can prepare the commercial red fluorescent powders which has good powder fluidity, good coating performance, good dispersion performance and good luminescence. The prepared red fluorescent powder of the yttrium europium oxide has the advantages of good fluidity, good coating performance, good dispersion performance and good luminescence.

The method for preparing sodium chromate by calcining chromite includes the following steps: pulverizing chromite and sieving with 200 mesh sieve, adding sodium carbonate whose added amount is 80-150% of chromite amount, and adding magnesite, baudisserite, periclase, brucite or synthetic magnesium oxide, magnesium hydroxide and magnesium carbonate and calcining them at 1000-1200 deg.c for 10-60 min. under the condition of oxidation atmosphere, then extracting clinker and dissolving sodium chromate so as to obtain the goal of preparing sodium chromate. The conversion rate of chromite can be up to 97-99.5%.