72 results about "Disulfur dioxide" patented technology

The invention discloses a method for synthesizing 3,5-dichlorobenzoyl chloride. The method comprises the following steps: carrying out sulfonation on benzoyl chloride by sulfur trioxide to obtain 5-chloroformyl metaphenylene disulfonic acid; carrying out chlorination by catalyzed triphosgene to obtain 5-chloroformyl metaphenylene disulfuryl chloride; finally, carrying out removal of sulfur dioxide chlorination to obtain 3,5-dichlorobenzoyl chloride. Compared with an existing preparation method, the method disclosed by the invention has the characteristics of stable chlorinating agent, high production safety, small amount of three wastes, no requirement for recovering and treating a great amount of dangerous byproducts, no requirement for refining a coarse product, low production cost and the like and is suitable for industrial production.

The invention discloses a color fixative for an apple or apple product, comprising 1.35-2.3 parts by weight of citric acid, 0.1-0.6 part by weight of sodium chloride, 0.07-0.21 part by weight of calcium oxide, 0.1-0.6 part by weight of D-sodium erythorbate and 98.38-96.29 parts by weight of water. The color fixative for the apple or apple product, provided by the invention, has the beneficial effects that safety problems caused by excessive sulfur in parts of apple products are solved, and after the apple or apple product is treated by using the color fixative provided by the invention, the original color and luster of the apple can be remained during processing, brown stains are reduced, and the residual sulfur dioxide in the product is reduced. Substances including the citric acid, the sodium chloride, the calcium oxide and the D-sodium erythorbate which are used in the invention are all safe and nontoxic, and the color fixative provided by the invention achieves the best color fixation effect by utilizing the synergistic effect of all color fixatives.

The invention discloses a safe stable type Karl Fischer reagent which comprises the following components in percentage by mass: 60-64 percent of diethylene glycol monomethyl ether, 8-12 percent of diethanol amine, 3.5-5.5 percent of pyridine, 12-15 percent of sulfur dioxide and 8-12 percent of iodine. The preparation method of the safe stable type Karl Fischer reagent comprises the following steps of: adding the diethylene glycol monomethyl ether, the diethanol amine and the pyridine in a reaction kettle and mixing; introducing the sulfur dioxide; after the gas is introduced, cooling the mixed solution below 25DEG C; and adding the iodine and stirring the mixed solution until the iodine is completely dissolved and obtaining a target product. According to the safe stable type Karl Fischer reagent and the preparation method thereof disclosed by the invention, original poisonous dangerous solvent is replaced by a safety type solvent, so that the safe stable type Karl Fischer reagent is non-poisonous, safe, environment-friendly and stable in quality; and after the safe stable type Karl Fischer reagent is stored for a long time, the titer is still within a usable range.

The invention discloses a recycling equipment and method of carbon disulfide in the hydrogen sulfide, which is characterized by the following: injecting hydrogen sulfide with carbon disulfide in the Claus recycling system directly; maintaining inner catalyst active property in the Claus reactor; sending the hydrogen sulfide with carbon disulfide in the adsorbing reactor to proceed adsorb and desorb operations alternately; transmitting the desorbed carbon disulfide in the refining unit to recycle carbon disulfide.

The invention relates to application of an LZQ fluorescent probe to simultaneous detection of SO2 and HSA. The structural formula of the LZQ fluorescent probe is as follows: (the formula is as shown in the description). According to the preparation method, 3-aldehyde-7-diethylamino-coumarin and nitrile benzothiazole serve as raw materials. The probe can detect sulfur dioxide derivatives sulfite and hydrosulphite in a blue channel and can detect HSA efficiently in a red channel; furthermore, the HSA can catalyze reaction among the probe, the sulfite and the hydrosulphite. The fluorescent probecan be used for detecting the HSO3<-> content and the HSA content in cells.

The invention provides an indole salt-coumarin derivative, and a synthesis method and an application thereof. The English name of the derivative is (E)-1-(2-carboxyethyl)-2-(2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)vinyl)-3,3-dimethyl-3H-indol-1-ium, and the reagent is named as Mito-CI. The reagent can be used for efficiently and reversibly detecting sulfur dioxide. A detection method is characterized in that sulfur dioxide is detected through a fluorospectro photometer in a pure PBS buffer solution with the pH value of 7.4. The detection process is simple, sensitive and rapid, and the detection result is accurate.

The invention relates to the technical field of production of bis (chlorosulfonyl) imide, in particular to a production process of bis (chlorosulfonyl) imide. The production process of the bis (chlorosulfonyl) imide comprises the steps of adding sulfamic acid and thionyl chloride into a reaction kettle until solids are completely dissolved, then adding sulfur trioxide into the reaction kettle at a constant speed, after the sulfur trioxide is completely added, heating to the temperature of 90-120 DEG C, continuing to react for 5-10 hours, restoring to normal pressure, opening a condensate outlet valve of a condenser, continuing to react for 1-3 hours, carrying out reduced pressure rectification until no condensate flows out of the condenser, and obtaining the target product bis (chlorosulfonyl) imide. Compared with an original chlorosulfonic acid method process, the production process has the advantages that the hydrogen chloride waste gas amount is reduced by 1/3, the sulfur dioxide tail gas can be recycled and reused in a thionyl chloride production device, the yield of three wastes is further reduced, and the production process belongs to an innovative process meeting the development requirements of the green chemical industry.

The invention discloses a preparation method of luteolin. The preparation method comprises following steps: fully dissolving rutin in an alkaline solution with a pH of 10 or more; adding a reducing agent composed of thiourea dioxide, potassium chloride, and potassium carbonate into the solution, wherein the ratio of the reducing agent to rutin is 5-24:1, stirring the solution until the solution becomes clear; and controlling the temperature in a range of 60 to 90 DEG C to carry out reactions for 1 to 2 hours to obtain luteolin. The preparation method has the advantages of simple technology, low cost, mild reaction conditions, short production time, and high yield, and is suitable for industrial production.

The invention discloses 3-sulfonylcoumarin and a preparation method thereof. The preparation method includes: in an organic solvent, allowing arylamine and phenyl phenylpropiolate to react with rongalite to obtain 3-sulfonylcoumarin compound. The structure of the 3-sulfonylcoumarin compound is confirmed by characterization via 1H NMR (nuclear magnetic resonance), 13C NMR, HRMS (high resolution mass spectrometry) and other processes. The preparation method has the advantages that the reaction herein is performed under mild conditions, rongalite is used as a sulfur dioxide source, sulfonyl reaction is achieved directly, and the 3-sulfonylcoumarin compound is constructed; the raw materials for the reaction are simple and easily accessible, the usage of sulfonyl chloride in traditional synthetic processes is avoided, and the preparation method is suitable for large-scale preparation and has a promising application prospect.

The invention discloses an alkyl alkyl sulfone compound as shown in a formula (1) (See the specification) and a synthesis method of a reagent as shown in a reaction formula (A) (See the specification). Alkyl p-methanesulfonate, an inorganic sulfur reagent and alkyl halide are used as reaction raw materials and react in a solvent under the action of alkali, a reducing agent and an additive to obtain a series of alkyl alkyl sulfone compounds. According to the invention, the alkyl alkyl sulfone compound is constructed in one step by taking an inorganic sulfur reagent as a sulfur dioxide source under a reduction condition, so that the defect of traditional synthesis of an alkyl alkyl sulfone compound through thioether oxidization is avoided; and the alkyl alkyl sulfone compound developed by the invention can successfully realize the connection of complex molecules.

The invention provides a method for measuring the content of acid mist in sulfuric acid production tail gas. The measurement method comprises the steps of sampling, preparing a sample, measuring, drawing a standard curve and calculating a result. By means of sampling at a constant speed, acid mist in sulfuric acid production tail gas is absorbed by using a dilute alkali solution, sulfate ions in a sample solution react with barium chloride under a neutral condition to generate white precipitate of barium sulfate and form turbid liquid, and a hydrochloric acid solution is added into the sample solution, so that the influence of barium sulfite white precipitate generated by sulfur dioxide and barium chloride in the tail gas on the result can be effectively eliminated, and then the absorbance is determined. The sulfate ion concentration and the absorbance have a good linear relationship within a certain range, and the content of sulfate radicals in a sample is determined by setting a standard curve and comparing the measured absorbance of a sample solution with the standard curve. The measurement method is simple and convenient, low in cost and high in accuracy, used equipment is simple and easy to obtain, and application of small and medium-sized chemical enterprises is facilitated.

The invention belongs to the field of organic chemistry, and particularly relates to a synthesis method of gamma-keto sulfone compounds. The structure of the compounds is characterized and confirmed by methods such as 1HNMR, 13CNMR and high-resolution mass spectrometry. According to the method, no metal catalyst is needed, and the gamma-keto sulfone compound is obtained through a reaction of substituted cyclopropanol, a sulfur dioxide substitute and alkenyl pyridine. The synthesis method of the gamma-keto sulfone compound has the advantages of mild conditions, simplicity, high efficiency, highreaction yield, wide substrate application range, high product purity, and convenience in separation and purification and has a high application value.

The invention discloses a method for removing oxygen in chlorination reaction gas. The specific technological process includes that the chlorination reaction gas and second matter enter a reactor, the oxygen in the chlorination reaction gas and the second matter spontaneously react or a reaction happens under the outer field initiating condition to generate third matter, and third matter plays no role on a chlorination reaction or the generated role is not as remarkable as the role on the oxygen. The second matter is gas containing any one or two or more of sulfur dioxide, nitric oxide, hydrogen sulfide and the like; and the second matter can also be composed of any one or two or more of iron, sodium sulfite, an oxime type deoxidant, an amine type deoxidant, quinoline compounds, erythorbic acid and sodium salt thereof, and the like. The method for removing the oxygen in the chlorination reaction gas has the beneficial effects of being simple in technological process, high in deoxidizing efficiency, good in deoxidizing effect and the like, and is especially suitable for removing oxygen in chlorination reaction gas in the process of preparing chlorinated high polymer resin through a gas-solid phase method.

The invention relates to the technical field of chemical synthesis, and particularly discloses a synthesis method of a beta-chloro-alpha, gamma-dicarbonyl compound. The synthesis method comprises thefollowing steps: under a solvent-free condition, taking an alpha, gamma dicarbonyl compound shown as a formula (I) as a raw material, taking anhydrous aluminum chloride as a catalyst, and introducingchlorine to carry out chlorination reaction, so as to obtain the beta-chlorinated alpha, gamma dicarbonyl compound shown as a formula (II). The beta-chloro-alpha, gamma-dicarbonyl compound shown in the formula (II) is prepared through a chlorination reaction by taking chlorine as a chlorination reagent and taking anhydrous aluminum chloride as a catalyst under a solvent-free condition, a product with the purity of more than 90% can be obtained only through simple post-treatment of a reaction product, the yield can reach 90% or above. The method has the advantages of mild reaction conditions, simple process operation, no generation of sulfur dioxide polluting the environment, greenness, environmental protection, and suitableness for large-scale industrial production.

The invention discloses a method for extracting sodium sulfite and sodium sulfate by using sulfur dioxide-containing flue gas and a system, and the method comprises the following steps: collecting thesulfur dioxide-containing flue gas, and treating to obtain a sulfur-containing solution; sequentially transferring the sulfur-containing solution into a multi-stage evaporator and a three-in-one separator to respectively obtain a sodium hydrogen sulfite solution and a filter cake which contains sodium sulfate; neutralizing the sodium hydrogen sulfite solution to obtain sodium sulfite; and dissolving the filter cake and carrying out centrifugal separation treatment to obtain sodium sulfate. The invention provides the method for extracting sodium sulfite and sodium sulfate by using the sulfur dioxide-containing flue gas. The method comprises the following steps: before a neutralizing step, the multi-stage evaporator and the three-in-one separator are additionally arranged; temperature control negative pressure concentration is achieved in the multi-stage evaporator by means of the solubility difference of sodium hydrogen sulfite and sodium sulfate, Na2SO4 crystals are enriched in the three-in-one separator, industrial waste is recycled, and the problem that Na2SO4 is difficult to lead out and separate in the traditional process is solved.

As an important intermediate and product in production, sulfonate is widely applied to various fields, such as anionic surfactants, reaction intermediates and the like. However, in the sulfonation process, sulfur trioxide is generally adopted as a sulfonating agent, and in the sulfonation reaction process, the mixing effect with raw materials is poor, the heat release is severe, and the purity is low. The invention provides a method for carrying out sulfonation reaction on sulfur dioxide serving as a sulfonating agent and unsaturated alkane of an electron withdrawing group in the presence of an acid-binding agent. The method has the advantages of mild reaction conditions, simple process, short reaction time and high yield.

The invention relates to a fluorescent probe for detecting a sulfur dioxide derivative, a detection object, and a preparation method and application of the fluorescent probe. The sulfur dioxide derivative is a salt with sulfite or bisulfite ions, and the structural formula of the fluorescent probe is as described in the specification. In the formula, TfO<-> is trifluoromethanesulfonate ions. The fluorescent probe disclosed by the invention is a colorimetric far-infrared sulfite/bisulfite fluorescent probe, has full water solubility, can be directly dissolved in water, and does not need to be dissolved by an additional organic solvent; the response of the probe is fast, and detection can be completed within 15 s; a color development mode during detectionis a mode from a colorless state to acoloredstate, so direct naked eye detection can be realized, the detection is more visual and convenient, and the rate of false positive is low; and the lowest detection limit of sodium hydrogen sulfite is 0.11 [mu]M, and sensitivity is higher. The probe of the invention not only can meet the detection requirements of sulfite/bisulfite in organisms, but also can realize rapid detection of sulfite/bisulfite in food or medicines.

The invention discloses a preparation method of caramel color by an ammonium sulfite method. The preparation method comprises the following steps: 1) adding syrup into a reaction kettle, heating to 80-90 DEG C, adding sulfite, ammonia or/and ammonium salt, adjusting the temperature in the reaction kettle to 130-135 DEG C and the pressure to 0.10-0.15 MPa, and reacting for 30-60 minutes; 2) adjusting the temperature in the reaction kettle to 120-125 DEG C and the pressure to 0.05-0.1 MPa, and reacting for 120-180 minutes; 3) adjusting the temperature in the reaction kettle to 115-120 DEG C, adjusting the pressure to 0.01-0.05 MPa, and reacting for 120-180 minutes; and 4) adjusting the temperature in the reaction kettle to 50-60 DEG C, adjusting the pressure to normal pressure, and filtering. In the caramelization reaction process, escape of free sulfur dioxide is promoted by gradually reducing the pressure in the reaction kettle, and the residual amount of sulfur dioxide in the finallyprepared caramel color is lower than 0.03% and is lower than that of a conventional ammonium sulfite method caramel color product by 70% or above.

The invention belongs to the technical field of organic chemistry, and particularly relates to a preparation method of dialkyl sulfone compounds. The preparation method comprises following steps: under catalysis of visible light, various simple or complex alkyl substituted N-alkyl pyridinium salts and a photocatalyst are adopted to generate alkyl free radicals, sulfonyl free radicals are obtainedthrough cascade reaction with sulfur dioxide, and silyl enol ether is attacked, so that a series of dialkyl sulfone compounds are efficiently constructed. According to the method, the dialkyl sulfonecompounds can be efficiently, simply and conveniently synthesized, sulfonyl-derived potassium metabisulfite required by the reaction is a cheap and easily available chemical raw material, the use of strongly acidic sulfonic acid and sulfonyl chloride in the traditional sulfonyl compound synthesis is avoided, and the method has the advantage of large-scale industrial preparation.

The invention provides a preparation method of sodium sulfite, and relates to the technical field of industrial chemical engineering. The preparation method of sodium sulfite comprises the following steps: (1) collecting flue gas for preparing sulfuric acid, and then filling the collected flue gas into a sodium hydroxide solution to obtain a first mixed solution; (2) filtering the first mixed solution, and performing solid-liquid separation to obtain a second mixed solution; (3) putting the second mixed solution into a reaction container with a gas guide tube, and then adding sulfuric acid to react to generate sulfur dioxide; (3) weighing the mass of the collected sulfur dioxide, and adding the sulfur dioxide into the first sodium carbonate solution to obtain a sodium hydrogen sulfite solution; (4) adding a second sodium carbonate solution into the sodium hydrogen sulfite solution in the step (3), and completely reacting to obtain a sodium sulfite solution; and (5) carrying out evaporative crystallization on the sodium sulfite solution to obtain sodium sulfite crystals. Sodium sulfite with the purity of 97.6% or above can be obtained, and no complex intermediate product is generated in the whole process.

A first method for determining an amount of water in a sample includes the step of providing a reagent comprising: sulfur dioxide or a derivative thereof; a base; an optional hydrogen halide or hydrogen halide donor; a solvent; and a sulfonic acid; and the step of titrating the sample with the reagent. A second method for determining an amount of water in a sample includes the step of providing the aforementioned reagent, combining the sample with the reagent; and adding a source of iodine to the sample and/or the reagent. The reagent may alternatively consist essentially of sulfur dioxide or a derivative thereof; imidazole and/or a derivative thereof; an optional hydrogen halide or hydrogen halide donor; acetonitrile; methane sulfonic acid; and methanol and/or ethanol.

The invention belongs to the field of organic synthesis, and relates to a method for preparing 4-acetamidobenzene sulfinic acid. The method comprises the steps: taking acetanilide and sulfur dioxide as raw materials, ionic liquid as a catalyst and the third dispersed phase particles as an accelerant, carrying out catalytic reaction in a closed reaction kettle with a self-suction stirring device to obtain the 4-acetaminobenzene sulfinic acid with high yield. According to the method disclosed by the invention, the reaction time can be remarkably shortened, and the yield of the 4-acetaminobenzene sulfinic acid can reach 89.6%.