51results about How to "The process is clean and environmentally friendly" patented technology

The invention relates to a preparation method of atorvastatin calcium. The method comprises the steps that 5-methyl--2-benzene-1-(4-fluorophenyl)-3-(phenyl amine formyl)-1,4-hexanedione as a starting material, and subjected to cyclization, hydrolysis, aldol condensation, asymmetric hydrogenation, resolution and salifying reaction, and atorvastatin calcium is obtained. The method is short in synthetic route, rich in raw material source, easy and simple to operate and mild in reaction condition and has a good industrialization prospect.

A process for all-wet recovery of valuable elements in a complex low-grade sulphide ore comprises the following steps: crushing and grinding a raw material, sieving the crushed and ground raw material, performing size mixing by use of a sodium hydroxide solution, and after that, performing pressurized oxidizing leaching to obtain an alkaline-leached solution and alkaline-leached residues; acidizing the alkaline-leached solution to obtain a lead sulfate product and a heavy lead solution, and performing potential reduction control step by step on the heavy lead solution to obtain crude selenium powder, crude tellurium powder and a post-reduction solution; performing copper-soaking on the alkaline-leached residues by use of a sulfuric acid solution to obtain copper-leached residues and a copper-leached solution; performing antimony and bismuth soaking on the copper-leached residues by use of an acid liquor containing chloride ions to obtain an antimony-leached solution and antimony-leached residues, feeding the antimony-leached slags to noble metals for recovery, and adjusting the pH of the antimony-leached solution step by step to obtain antimony residues and bismuth residues; adjusting the pH of the copper-leached solution to obtain iron residues and an iron-removed solution, wherein the iron residues serve as a waste water treatment additive, and the iron-removed solution is subjected to zinc dust replacement to obtain copper powder and a post-replacement solution; and merging the post-reduction solution and the post-replacement solution, and performing concentration and crystallization to obtain heptahydrate. The process is good in comprehensive recovery effect, strong in adaptation to the raw material, clean and environment-friendly in process, low in demand on equipment, adjustable in implementation scale and high in practicability.

The invention relates to a method for extracting vanadium from vanadium slag through blank roasting and quaternarization. The method comprises the steps of adding the vanadium slag to a fluidized bedfurnace for blank roasting; mixing roasted clinkers obtained through blank roasting, ammonium salt solutions and regulators for quaternarization, and leaching upon completion of quaternarization; andobtaining vanadium-containing solutions after solid-liquid separation. According to the method provided by the invention, by adopting the fluidized bed furnace as equipment for roasting the vanadium slag, and adding an appropriate amount of the regulators, the heat transfer efficiency is improved, and the roasting time is shortened; the production energy consumption is reduced, and meanwhile the adverse effect of silicon-containing phases is eliminated; and the vanadium conversion rate by quaternarization and the solid-liquid separation performance are improved. With the method provided by theinvention, the phenomena of bonding and sintering hardly occur in the high-temperature roasting process, so that oxygen comes into sufficient contact with vanadium slag particles, and the vanadium conversion rate is improved greatly; meanwhile, the amount of ammonium salt and the production cost are reduced; the cyclic utilization of ammonium salt media can be achieved, and the whole process hasno waste water discharged; and the method has good application prospects.

The invention relates to a process and application for separating and recovering zinc-magnesium sulfate double salt from sulfate solution, and belongs to the technical field of wastewater treatment. First, the sulfate solution is added to the precooler and the crystallization mother liquor is used for heat exchange and precooling, and then added to the crystallization reactor. The first stage is cooled at a cooling rate of 0.2 to 0.5 °C / min, and the cooling is stopped when the solution begins to become turbid. , keep stirring for 15-30min; in the second stage, cool down at a cooling rate of 0.5-1 ℃ / min, control the end point temperature to be more than 10 ℃ lower than the temperature of the first stage, and at the same time be higher than the freezing point temperature of the solution, keep stirring for 20-60min. After the reaction, centrifugal filter was adopted to obtain the zinc-magnesium sulfate double salt product. The crystallization mother liquor obtained by filtration is returned to the precooler as a precooling medium.