摘要:
The present invention relates to a novel nitration process of 2-chloro-4-fluorobenzoic acid to 2-chloro-4-fluoro-5-ni-trobenzoic acid, 2-chloro-4-f luoro-3-nitrobenzoic acid and 3,5-dinitro-2-chloro-4-fluorobenzoic acid; purifying the crude reaction product; and recovering 2-chloro-4-fluoro-5-nitrobenzoic acid in an essentially pure form, which can be used in the synthesis of the herbicide saflufenacil.
摘要:
The present invention relates to a new chemical synthesis, intermediates and catalysts useful for the preparation of the neprilysin (NEP) inhibitor sacubitril, inter alia via nitro 5 compounds. It further relates to new intermediate compounds and their use for said new chemical synthesis route, as well as a new catalyst ligand.
摘要:
The present invention relates to zeolitic adsorbents based on agglomerated crystals of FAU zeolite containing barium and/or potassium, with large external surface area, combining optimum properties in terms of selectivity and mechanical strength. These adsorbents find applications in the separation of cuts of C8-aromatic isomers and notably of xylenes, in the separation of isomers of substituted toluene such as nitrotoluene, diethyltoluene, toluenediamine, in the separation of cresols, and in the separation of polyhydric alcohols such as sugars.
摘要:
The present invention relates to zeolitic adsorbents based on agglomerated crystals of FAU zeolite comprising barium and/or potassium, with large external surface area, combining optimum properties in terms of selectivity and mechanical strength.These adsorbents find applications in the separation of cuts of C8-aromatic isomers and notably of xylenes, in the separation of isomers of substituted toluene such as nitrotoluene, diethyltoluene, toluenediamine, in the separation of cresols, and polyhydric alcohols, such as sugars.
摘要:
The invention relates to a method for producing dinitrotoluene, comprising the following steps: a) nitrating toluene with a mixture of nitric acid and sulfuric acid and subsequently separating a sulfuric-acid-containing aqueous phase that arises in the nitration, wherein a raw dinitrotoluene is obtained, b) washing the raw dinitrotoluene in a water wash with neutral and/or alkaline washing water, wherein a pre-cleaned dinitrotoluene, which contains at least water in addition to dinitrotoluene, is obtained after the washing water used in the last wash has been separated, and c) separating the water from the pre-cleaned dinitrotoluene, d) collecting the waste water from steps a), b), and/or c), e) optionally extracting the collected waste water from step d) with toluene and returning the thus obtained organic phase to step a), f) freeing the collected waste water from step d), or, if the optional step e) is performed, the extracted waste water from step e), of toluene in a toluene stripper, wherein a toluene-containing exhaust gas flow is obtained, g) feeding at least one exhaust gas flow from steps a), b), c), d), e), or f) into an exhaust gas condenser and removing the toluene contained in the at least one exhaust gas flow in said exhaust gas condenser, wherein the method comprises the following further step: h) feeding the exhaust gas flow arising in step g) after the condensing out of the toluene to a thermal exhaust air cleaning, wherein nitrogen is added to the exhaust gas flow to be fed to the exhaust gas condenser or to the exhaust gas flow leaving the exhaust gas condenser, wherein preferably a nitrogen concentration in the exhaust gas flow of at least 0.1 vol % is set, especially preferably of at least 0.5 vol %.
摘要:
The invention relates to a method for producing dinitrotoluene, comprising the following steps: a) nitrating toluene with a mixture of nitric acid and sulfuric acid and subsequently separating a sulfuric-acid-containing aqueous phase that arises in the nitration, wherein a raw dinitrotoluene is obtained, b) washing the raw dinitrotoluene in a water wash with neutral and/or alkaline washing water, wherein a pre-cleaned dinitrotoluene, which contains at least water in addition to dinitrotoluene, is obtained after the washing water used in the last wash has been separated, and c) separating the water from the pre-cleaned dinitrotoluene, d) collecting the waste water from steps a), b), and/or c), e) optionally extracting the collected waste water from step d) with toluene and returning the thus obtained organic phase to step a), f) freeing the collected waste water from step d), or, if the optional step e) is performed, the extracted waste water from step e), of toluene in a toluene stripper, wherein a toluene-containing exhaust gas flow is obtained, g) feeding at least one exhaust gas flow from steps a), b), c), d), e), or f) into an exhaust gas condenser and removing the toluene contained in the at least one exhaust gas flow in said exhaust gas condenser, wherein the method comprises the following further step: h) feeding the exhaust gas flow arising in step g) after the condensing out of the toluene to a thermal exhaust air cleaning, wherein nitrogen is added to the exhaust gas flow to be fed to the exhaust gas condenser or to the exhaust gas flow leaving the exhaust gas condenser, wherein preferably a nitrogen concentration in the exhaust gas flow of at least 0.1 vol % is set, especially preferably of at least 0.5 vol %.
摘要:
The present invention provides a process for purifying a monoterpene or sesquiterpene having a purity greater than about 98.5% (w/w). The process comprises the steps of derivatizing the monoterpene (or sesquiterpene) to produce a monoterpene (or sesquiterpene) derivative, separating the monoterpene (or sesquiterpene) derivative, and releasing the monoterpene (or sesquiterpene) from the derivative. Also encompassed by the scope of the present invention is a pharmaceutical composition comprising a monoterpene (or sesquiterpene) having a purity greater than about 98.5% (w/w). The purified monoterpene can be used to treat a disease such as cancer. The present monoterpene (or sesquiterpene) may be administered alone, or may be co-administered with radiation or other therapeutic agents, such as chemotherapeutic agents.
摘要:
The present invention relates to a method for removing impurities from nitrated crude products obtained during the nitration of nitratable aromatic compounds, after removal of the final nitrating acid, by treatment with a washing medium, and also to a plant or apparatus suitable for implementing this method. Further provided by the invention is a production plant for the nitration of nitratable aromatic compounds with subsequent purification of the nitrated products.
摘要:
Process for scrubbing a crude mixture which is obtained in the nitration of toluene after separating off the nitrating acid and comprises dinitrotoluene, nitric acid, nitrogen oxides and sulfuric acid, which comprises two scrubbing steps (WS-I) and (WS-II), wherein i) in a first scrubbing step (WS-I), the crude mixture is extracted with a scrubbing acid I comprising nitric acid, nitrogen oxides and sulfuric acid in a scrub comprising at least one extraction stage, where the scrubbing acid discharged from the first extraction stage (WS-I-1) of the first scrubbing step (WS-I) has a total acid content of from 10 to 40% by weight and a content of from 80 to 350 ppm of hydrocyanic acid, giving a prescrubbed crude mixture, ii) in a second scrubbing step (WS-II), the prescrubbed crude mixture comprising dinitrotoluene is extracted with a scrubbing acid II in a scrub comprising at least one, preferably at least 2, extraction stage(s), where the scrubbing acid discharged from the first extraction stage (WS-II-1) of the second scrubbing step (WS-II) has a pH of less than or equal to 4, giving a dinitrotoluene-comprising mixture which is essentially free of nitric acid, sulfuric acid, nitrogen oxides and hydrocyanic acid and has a content of not more than 300 ppm of nitric acid and nitrogen oxides, not more than 3 ppm of sulfate and not more than 50 ppm of hydrocyanic acid.
摘要:
The present invention relates to a continuously operated adiabatic process for the preparation of nitrobenzene by nitration of benzene with nitric acid and sulfuric acid, in which the dilute sulfuric acid obtained after the nitration has taken place and the crude nitrobenzene has been separated off from the aqueous phase is concentrated for the purpose of re-use in the nitration, and after its concentration, at least one minute before it comes into contact with fresh nitric acid again an oxidizing agent is added such that a concentration of the oxidizing agent of from 10 ppm to 5,000 ppm, based on the total weight of the concentrated sulfuric acid to be recycled into the nitration, is established.