45 results about "Stoddard solvent" patented technology

The invention relates to an extraction, rectification and separation method and an extraction, rectification and separation process for a solvent containing a tetrahydrofuran-carbinol system which take ethylene glycol as an extractions solvent, and take tetrahydrofuran and carbinol as products. In the drug synthesis process in the pharmaceutical industry, a great quantity of solvents containing the tetrahydrofuran, the carbinol and the like are used, and a mixed liquid waste is generated. Under the normal temperature and normal pressure, the boiling temperatures of the tetrahydrofuran and the carbinol are extremely similar (the boiling temperature of the tetrahydrofuran is 65.4 DEG C and the boiling temperature of the carbinol is 64.8 DEG C), so that the tetrahydrofuran and the carbinol are difficult to separate by adopting a common rectification operation. In addition, the tetrahydrofuran and the carbinol are good in intersolubility and can be well dissolved with great majority of organic or inorganic solvents so as to be incapable of being separated by an extraction operation. According to the method and the process, the waste solvent containing the tetrahydrofuran-carbinol system can be recovered by adopting an extraction and rectification manner, meanwhile, an extracting agent is recycled, so that the obtained tetrahydrofuran and carbinol products are high in purity, impurities are few, the recovered solvent can be recycled in the drug synthesis process, further not only is the cost of pharmacy process reduced, and also the pollution of the waste solvent to the environment is alleviated greatly.

The invention relates to a vacuum rectification method using a super-gravity bed as core separating equipment, and discloses a process for separating and recycling a waste solvent in the synthetic process of statins or other medicines and recovering tert-butyl acetate in the solvent. During operation, the waste solvent enters from a place located between the two-layer and three-layer rotors of thesuper-gravity bed, wherein the rotating speed is 1000r/min, the reflux ratio is 4-10, the vacuum degree at the top of a tower is 20kPa-70kPa, and the temperature of a tower kettle is controlled at 70DEG C-85 DEG C, a tert-butyl acetate product with higher purity can be recovered in the tower kettle, the purity can reach 95% or more, the residual amount of isoprene is less than 1%, and the moisture content is less than 1000ppm, thereby fully meeting the requirements of recycling; and compared with traditional tower-type rectification operation, the process provided by the invention has the advantages of having a simple technological procedure, low energy consumption, a small occupied area of equipment, and high recovery rate of the product tert-butyl acetate, and being capable of effectively improving economic benefits.

The invention relates to the field of waste liquid treatment, and discloses a waste solvent treatment method. The method comprises the following steps that: (1) reduced pressure distillation is performed, specifically, a cleaned waste solvent is introduced into an evaporator for reduced pressure distillation, after the steam of the waste solvent passes through the top of the evaporator, liquid enters a solvent receiving intermediate tank; (2) drying and recycling are performed, specifically, solid-liquid mixed impurities are : introduced into a dryer for heating, so that a gas-phase part of the solvent flows into the solvent receiving intermediate tank after being condensed; (3) primary reduced pressure rectification is performed, specifically, the solvent in the solvent receiving intermediate tank is introduced into a rectifying tower I, light component impurities are extracted from the tower top of the rectifying tower I, and a product mixture is extracted from the tower kettle of the rectifying tower I; and (4) secondary reduced pressure rectification is performed, specifically, the product mixture is introduced into a rectifying tower II, monoethanolamine is extracted from thetower top of the rectifying tower II, and ethylene glycol is extracted from the tower kettle of the rectifying tower II. With the method adopted, the problem that valuable components in the waste solvent are wasted due to the fact that the waste solvent is treated in an incineration mode in the prior art can be solved.

The invention relates to a method and process for solvent extraction, rectification and separation of a tetrahydrofuran-methanol system using ethylene glycol as an extraction agent and tetrahydrofuran and methanol as products. Generally, pharmaceutical companies use a large amount of solvents such as tetrahydrofuran and methanol in the production process of pharmaceutical products, resulting in mixed waste liquid of solvents. Under normal temperature and pressure, the boiling points of tetrahydrofuran and methanol are very close (65.4°C for tetrahydrofuran and 64.8°C for methanol), so it is difficult to separate them by general rectification. In addition, tetrahydrofuran and methanol have good mutual solubility, and can be well miscible with most organic or inorganic solvents, so it is impossible to separate them by extraction. The present invention adopts the way of extraction and rectification to recover the waste solvent containing tetrahydrofuran and methanol system, and at the same time, the extractant is recycled, and the obtained tetrahydrofuran and methanol products have high purity and less impurities, and can be used for solvent recycling in pharmaceutical companies. It not only reduces the cost of the pharmaceutical process, but also greatly reduces the pollution of the waste solvent to the environment.

The invention provides a recovery method of N, N-dimethylacetamide. The method comprises the following steps: enabling a waste solvent to enter a distillation tower, carrying out side line gas phase extraction, pressurizing, directly introducing an obtained product into a membrane separation unit, and dehydrating, so as to obtain an N, N-dimethylacetamide product. According to the invention, through a distillation tower side line gas phase extraction and membrane separation coupling mode, the process is simplified, the process energy consumption is reduced, especially the material heating process before membrane separation is saved, the process is green, the reuse rate is high, the waste discharge amount is small, and the industrialization is favorably realized. Meanwhile, the product purity of the obtained N, N-dimethylacetamide is higher than 99.9%, the moisture content is lower than 200 ppm, and the requirement for solvent application is completely met.

The invention discloses a method for recovering and purifying propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate from electronic waste liquid, and relates to the field of solvent recovery and purification. The method comprises the following steps: S1, taking mixed waste solvents propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate, adding an impurity removal reactant, and carrying out reaction through a mixing mechanism to remove impurities and other impurities; S2, adding the mixed solution of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate into an organic solvent which forms azeotropy with water, distilling at the temperature lower than the boiling point of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate, distilling out water and an entrainer, and reserving a mixture of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate; and S3, obtaining an entrainer water azeotrope at the tower top. According to the method, the waste propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are recycled, the pollution degree of the waste solvent generated in electronic production to the environment is reduced, and the production cost is reduced.

The invention provides an extraction-rectification recovery method of N-methyl pyrrolidone. The N-methyl pyrrolidone is recycled by taking a selected solvent or a composite solvent as an extracting agent and an extraction-rectification technology as a core, and the method specifically comprises the following steps: firstly, extracting by using the extracting agent, rectifying an obtained extractedphase to respectively recycle the N-methyl pyrrolidone and the extracting agent, and refining the N-methyl pyrrolidone to finally obtain a product. According to the method, the extraction efficiencyof the selected extracting agent is high, the process technology is green, simple and convenient, the operability is high, the purity of the obtained N-methyl pyrrolidone is larger than 99.7%, the moisture content is lower than 200 ppm, the recovery rate is 97% or above, compared with other technological methods, the process energy consumption is remarkably reduced, and industrial production is facilitated.

The invention relates to a methyl tertbutyl ether-tetrahydrofuran rectification process, which takes rectification as a core method and aims at recycling an organic waste solvent in a statins medicinesynthetic process, wherein the methyl tertbutyl ether-tetrahydrofuran meets application requirement. According to the process, a waste solvent enters the space between the rotors in the second and third layers of a first high-gravity bed, the temperature of a tower top is controlled at 34-36 DEG C, the tower top product is layered with a decanter, and an isoprene coarse product is obtained from the top layer. A tower bottom material enters the space between the rotors in the first and second layers of a second high-gravity bed, the operation temperature of the tower top is controlled at 55-58DEG C, and a methyl tertbutyl ether-tetrahydrofuran mixed solvent with the purity more than 97% and the water content less than 1000 ppm is obtained from the tower top. According to the process, a recycling process using two in-series high-gravity beds is adopted. The process is simple in route, small in equipment space occupation, and low in energy consumption. The recycling utilization rate ofa regenerative solvent is improved, and the economic benefit of an enterprise is increased.

The invention belongs to the technical field of carboxylic ester extraction, and discloses a method for recovering PGMEA from an electronic PGMEA waste solvent. The method comprises the following steps: firstly, introducing the waste solvent into a film evaporator, heating by using steam to generate a waste solvent gas phase, introducing the waste solvent gas phase into a condenser, condensing to form a PGMEA semi-finished product, and introducing the PGMEA semi-finished product into a solvent receiving intermediate tank; introducing the PGMEA semi-finished product into a rectifying tower, and keeping the tower top pressure of the rectifying tower at 5-15 KPa, the tower top temperature of the rectifying tower at 48-52 DEG C, the tower kettle temperature of the rectifying tower at 85-89 DEG C, and the temperature of the side line of the rectifying tower at 82-86 DEG C; and finally, extracting PGMEA from the side line of the rectifying tower. According to the invention, the problem that the purity of the recovered PGMEA is low because the photoresist in the waste solvent cannot be removed in the prior art is solved.

The invention belongs to the technical field of organic chemical synthesis, and particularly relates to a preparation method of a 2-phenylbenzothiazole derivative. An existing 2-phenylbenzothiazole derivative is high in raw material pollution, high in price, long in reaction step, complex in reaction, low in yield and complex in post-treatment. The invention provides the preparation method of the 2-phenylbenzothiazole derivative. Substituted aryl carboxylic acid and o-aminothiophenol are used as raw materials to react to obtain the 2-phenylbenzothiazole derivative. No waste solvent is generated, less waste water is generated, and the atom utilization rate is high, so that the method is more environment-friendly.

The invention discloses a method for recovering a waste solvent of ethyl acetate, n-butyl alcohol and n-heptane, which comprises the following steps: (1) reducing the mass content of water in the solvent to obtain a mixture only containing ethyl acetate, n-butyl alcohol and n-heptane; (2) introducing the mixture of ethyl acetate, n-butyl alcohol and n-heptane into a first rectifying tower for azeotropic distillation to obtain n-butyl alcohol at the bottom of the tower and an azeotropic mixture of ethyl acetate and n-heptane at the top of the tower; (3) introducing the azeotropic mixture of ethyl acetate and n-heptane into a second rectifying tower, adding a mixed extractant composed of an extractant and an ionic liquid, and carrying out extractive distillation to obtain n-heptane at the tower top and a mixture of ethyl acetate and the mixed extractant at the tower bottom; and (4) continuously introducing the mixture of ethyl acetate and the extraction agent into a solvent recovery tower to obtain ethyl acetate at the top of the tower and a mixed extraction agent at the bottom of the tower. According to the method, ethyl acetate, n-butyl alcohol and n-heptane can be efficiently separated.

The invention discloses a method and equipment for recovering and purifying MTBE (Methyl Tert-Butyl Ether) waste solvent generated by synthesizing a drug intermediate. The method and the equipment have the beneficial effects that impurities in the waste solvent for synthesizing the drug intermediate are removed through a series of methods such as rectification, liquid-liquid extraction and the like, and an organic solvent still having recycling value is recovered. According to the recovery and purification method provided by the invention, the waste solvent for synthesizing the drug intermediate is separated through a series of low-energy-consumption processes of rectification and extraction, so that the solvent with recycling value is recycled, the pollution degree of the waste solvent to the environment in the pharmaceutical industry is reduced, and the production cost is reduced.

The invention discloses a dynamic separation and recovery device for a water-based paint cleaning solvent and a driving control method, and relates to the technical field of water-based paint cleaning solvent recovery. A cleaning solvent is collected through a cleaning closestool and enters a stock solution tank for standing and settling, supernatant liquid is filtered through a primary 50-micron filter bag, a 5-micron filter element and a UF membrane, then liquid is guided into a first-stage clear liquid tank, liquid in the first-stage clear liquid tank is filtered through an RO membrane, clear liquid enters a recovery solution tank, concentrated liquid filtered out through the UF membrane and the RO membrane flows back to the stock solution tank, and the concentrated liquid enters a second-stage clear liquid tank. The concentrated liquid which is left to stand and settled in the stock solution tank is guided into the paint mixing room concentrated liquid collecting tank, the clear liquid in the recovery solution tank is guided into the secondary proportioning tank, the solvent is supplemented in the secondary proportioning tank, the liquid in the secondary proportioning tank is guided into the paint mixing room solvent tank after the solvent is supplemented, and the cleaning solvent is supplied to the spray gun head of the robot. The recycling rate of the water-based paint waste solvent is increased, and the recycling time-consuming efficiency of the water-based paint waste solvent in the recycling process is improved.

The invention relates to a shoe polyurethane adhesive prepared from a recycled solvent, which is prepared from the following components: isophorone diisocyanate, poly (1, 4-butylene adipate), polyethylene glycol N-120, dimethylolpropionic acid, stannous octoate, the recycled waste solvent, deionized water, ethylenediamine, triethylamine and a tackifier. The processing method of the shoe polyurethane adhesive prepared from a recycled solvent comprises two steps. The processing process is optimized and screened, is scientific and stable, is easy to operate, and is low in toxicity compared with a traditional solvent type polyurethane adhesive. The waste solvent generated in the preparation process of the aqueous dispersion of the polyurethane adhesive is utilized, so that the effects of saving energy, reducing emission, protecting the environment and recycling resources are achieved. The film-forming property of the adhesive prepared from the recycled solvent is better than that of a pure water-based adhesive, so that the effect of reducing the cost is realized, and the emission of VOC is reduced. On the basis, the method has a good and wide application prospect.