Rhenium itself has no independent deposit, and is often dispersed in other non-ferrous ore bodies. It is mainly associated with molybdenite and mostly occurs in trace minerals such as molybdenum, copper, lead, zinc, platinum and niobium. Therefore, we should make full use of regional resources, give full play to regional advantages, and vigorously build the high-tech industry of scattered metals.
A former Soviet union carbide plant, oxidizing roasting – sedimentation method to extract the rhenium: flue gas containing a Re2O7 via leaching tower and wet electrostatic precipitator dust, the flue gas of Re2O7 soluble in water and generate high rhenium acid, soluble have Re2O7 aqueous solution circulating leaching flue gas accumulation to a certain concentration, take out a part of the solution for enrichment, join the potassium chloride, recovery of rhenium. In France, from the roasting-molybdenite flue gas, using the oxidation roasting-extraction method to extract rhenium: the Re2O7 in the flue gas is absorbed by sulfuric acid, and the rhenium in the absorption solution is extracted by isoamyl alcohol. Due to the huge difference in the distribution ratio D of rhenium and molybdenum, molybdenum and rhenium are well separated, which has become one of the leading processes in the production of rhenium. The main problem is that a third phase is often produced and rhenium recovery is low, only 75%. In addition, isoamyl alcohol is water-soluble, volatile, reagent consumption, high cost, and emit a pungent odor.
However, the above technology is the extraction of ammonium rhenate or rhenium oxide technology, in the existing technology to prepare rhenium trichloride technology is rarely reported.
The purpose is to provide a process for preparing rhenium trichloride from rhenium powder.
The technical scheme adopted is: a preparation method of rhenium trichloride, the method is as follows: The rhenium powder is evenly filled in the atmosphere furnace, into chlorine gas, slowly rise to 280-320℃, reaction 9-11h, cooling, when the temperature is reduced to 180-220℃, stop into chlorine gas, into nitrogen, and reaction at 180-220℃ for 3-4h, natural cooling to room temperature, the target product rhenium trichloride.
In the above preparation method, rhenium powder is uniformly filled in an atmosphere furnace with a thickness of 2-3cm.
The stage of temperature control: the rhenium powder is evenly filled in the atmosphere furnace, the furnace temperature will rise to 90-110℃, keep 1-2h, and then into chlorine gas, and then slowly rise to 280-320℃, reaction 9-11h, cooling. At a heating rate of 20℃/min, the temperature is slowly raised to 280-320℃. The gas flow rate of chlorine is controlled to be 1m3/h. The gas flow rate of nitrogen is controlled to be 3m3/h.
The beneficial effect is: the invention takes rhenium powder as raw material, by adopting the method of stage control temperature, the preparation of rhenium trichloride, the yield is greater than 80%, the economic benefits, social benefits and environmental benefits are significant.