19 results about "P-chlorotoluene" patented technology

The invention relates to the technical field of chemical synthesis, in particular to a preparation method of 2-sulfydryl-6-chlorobenzoic acid, which comprises the following steps: dissolving chlorobenzoic acid in dimethyl sulfoxide, adding sodium hydrogen sulfite, and stirring at room temperature; the preparation method comprises the following steps: dissolving mercaptobenzoate in dimethyl sulfoxide, adding sodium carbonate and dimethylamino, and reacting at high temperature; cooling to room temperature, and adjusting the pH value to be neutral by using dilute acid; adding into diethyl ether, uniformly mixing, adding into dilute acid, and standing for layering to obtain 2-sulfydryl-6-chlorobenzoic acid; the preparation method of the chlorobenzoic acid comprises the following steps: mixing parachlorotoluene with water, adding a supported catalyst, stirring and heating; after the temperature rises to 80 DEG C, adding potassium permanganate in batches for reaction; and filtering, adjusting the pH value to be acidic by using dilute acid, and then carrying out suction filtration and drying to obtain the chlorobenzoic acid. According to the preparation method disclosed by the invention, chlorobenzoic acid and mercaptobenzoate are subjected to a reaction to obtain 2-mercapto-6-chlorobenzoic acid with high yield; the method has the characteristics of simplified operation, energy consumption reduction, shortened production period and low production cost.

The invention belongs to the technical field of chlorotoluene tail gas treatment, and particularly relates to an acid-alkali washing circulating system for pretreatment of parachlorotoluene tail gas adsorption equipment, the acid-alkali washing circulating system comprises a supporting protection frame, and the inner wall of the supporting protection frame is fixedly provided with a neutralizing tower, a magnet plate II, a system fan and a chlorotoluene tail gas emission concentration cylinder; the output end of the system fan is fixedly connected with a gas conveying pipeline, the gas conveying pipeline is communicated with the chlorotoluene tail gas emission concentration cylinder and the neutralizing tower, the outer wall of one side of the top of the supporting protection frame is fixedly connected with a spraying pipe, and the branch end of the spraying pipe is fixedly connected with the outer wall of one side of the top of the neutralizing tower; an atomization spraying frame is fixedly installed on the inner wall of the top of the supporting protection frame, the chlorotoluene tail gas emission concentration barrel is communicated with an industrial workshop chlorotoluene tail gas emission pipe, and chlorotoluene tail gas in the chlorotoluene tail gas emission concentration barrel enters an outer layer protection barrel of the neutralization tower through a system fan; and chlorotoluene tail gas is sprayed out from the first exhaust port and the second exhaust port through the inner-layer exhaust funnel.

In highly selective oxidation of parachlorotoluene to parachlorobenzaldehyde, catalytic activity and selectivity were insufficient, the environmental impact was high, and there were issues with catalyst reusability. [Solution] The present invention provides a manganese oxide-supported cobalt chromium catalyst, a method for producing the same, and a method for producing parachlorobenzaldehyde by oxidizing parachlorotoluene using the same. This catalyst is prepared by dissolving a certain amount of manganese salt and metal salt precursors of cobalt and chromium, measured based on the support ratio, in deionized water and stirring to obtain a mixed solution. Acid is added to the resulting solution, and the mixture is heated and stirred. The resulting solid is then filtered, washed, and calcined. The resulting catalyst is used in the selective oxidation of parachlorotoluene, achieving high conversion and selectivity. The catalyst of the present invention is inexpensive to produce, environmentally friendly, and easy to recover and reuse. Furthermore, it exhibits excellent reaction activity and product selectivity despite relatively mild reaction conditions, making it suitable for industrial use.

The present application relates to the synthesis of pesticide compounds, in particular to a method for preparing a pyrasulfotole intermediate. The method comprises: (1) using p-chlorotoluene as a raw material, through nitration, chlorination, hydrolysis, or chlorination, hydrolysis, nitration, to obtain 3-nitro-4-chlorobenzaldehyde, (2) fluorination and reduction of 3-nitro-4-chlorobenzaldehyde to obtain 4-fluoro-3-amino benzaldehyde; (3) 4-fluoro-3-amino benzaldehyde is then contacted with chloroformate for reaction, and then chlorination to obtain compound IV; (4) compound IV is contacted with trifluorobutanamine ester under alkaline conditions for reaction to obtain compound I. The process for preparing compound I avoids using expensive raw material 2-chloro-4-fluorobenzoic acid, effectively reduces the cost of raw materials, reduces the three wastes generated in the process, and at the same time, the total yield of the reaction is high, and it is suitable for industrial mass production.

The present application relates to the field of synthesizing 2,4-dichlorotoluene, and in particular to a method for catalyzing the directional synthesis of 2,4-dichlorotoluene by parachlorotoluene. A method for catalyzing the directional synthesis of 2,4-dichlorotoluene by parachlorotoluene, comprising the following preparation steps: taking parachlorotoluene, a catalyst and an auxiliary agent, mixing, using chlorine as a chlorine source, heat-insulating the reaction, collecting the reactants, separating the reactants and collecting 2,4-dichlorotoluene; the catalyst includes one or more of aluminum chloride, ferric chloride, antimony trichloride and zirconium tetrachloride. The present application adopts a homogeneous catalyst, which has the advantages of stable properties, convenient purchase channels, no need for further processing, low toxicity and high product yield; and the catalyst application system has mature industrial technology, many separation methods, and the convenience and safety of operation can be fully guaranteed, which can not only effectively improve the effect of catalytic synthesis, but also synthesize and separate 2,4-dichlorotoluene with higher purity and yield.

The invention discloses a system for producing o-(p-) chlorobenzyl chloride by'reacting first and then separating 'mixed o-(p-) chlorotoluene. The invention discloses a process for producing o (p) chlorobenzyl chloride from mixed o (p) chlorotoluene by'reaction-separation ', which comprises the following steps: carrying out side chain photochlorination reaction on the mixed o (p) chlorotoluene and chlorine in a photochlorination reactor, feeding the chlorination liquid into a deacidification tower for degassing operation, feeding the deacidified chlorination liquid into a chlorotoluene removal tower for rectifying to remove the mixed chlorotoluene, and feeding the deacidified chlorination liquid into a dechlorination tower for dechlorination; a tower kettle material enters an o-chlorobenzyl chloride refining tower, an o-chlorobenzyl chloride product is extracted after a tower top material of the o-chlorobenzyl chloride refining tower is condensed, a tower kettle material enters an o-chlorobenzyl chloride removal refining tower, a tower top material of the o-chlorobenzyl chloride removal refining tower is condensed and then returns to the o-chlorobenzyl chloride refining tower, and a tower kettle material enters a p-chlorobenzyl chloride refining tower; and condensing a material at the top of the p-chlorobenzyl chloride refining tower, and extracting a p-chlorobenzyl chloride product. According to the method, the separation difficulty is reduced, and the separation energy consumption is saved.

The invention relates to the technical field of chemical synthesis, in particular to a preparation method of 3, 4-dichlorobenzotrifluoride, which comprises the following steps: firstly, adding dibenzoyl peroxide and N-hydroxyphthalimide into parachlorotoluene, and performing side chain chlorination reaction under ultraviolet irradiation and chlorine atmosphere to generate parachlorobenzotrifluoride; secondly, the obtained p-chlorobenzotrifluoride and tetrabutylammonium fluoride and potassium fluoride composite fluorination reagent are subjected to a fluorination reaction in the presence of a copper powder-1, 10-phenanthroline complex, and p-chlorobenzotrifluoride is prepared; and finally, under the catalysis of the mesoporous silica supported ferric trichloride catalyst, performing aromatic electrophilic chlorination on chlorobenzotrifluoride and sulfuryl chloride to obtain the high-purity 3, 4-dichlorobenzotrifluoride. Through synergistic application of photochemical chlorination, a composite fluorination system and the supported catalyst, the method has the advantages of mild reaction conditions, safe operation, high yield and good selectivity, and is suitable for industrial production.

The invention relates to the field of separation of parachlorotoluene and o-chlorotoluene, in particular to an adsorbent for separation of parachlorotoluene and o-chlorotoluene and a preparation method of the adsorbent. The adsorbent for separating parachlorotoluene and o-chlorotoluene comprises an adsorption carrier and separation adsorption particles coated on the surface of the adsorption carrier, and the separation adsorption particles are prepared by the following technical scheme: taking chromic nitrate and 2-aminoterephthalic acid, stirring and mixing, adding a sodium hydroxide solution, mixing, putting into a reaction kettle, heating, preserving heat and reacting; and collecting reactants, performing centrifugal separation, and performing vacuum drying to obtain the separation and adsorption particles. According to the technical scheme, chromic nitrate and 2-aminoterephthalic acid serve as raw materials to prepare separation and adsorption particles, m-xylene and o-xylene are stacked in pairs in the separation and adsorption particles, and the pi-pi effect between molecules is higher, so that p-xylene, o-xylene and m-xylene sequentially pass through the adsorbent material, and the separation and adsorption efficiency is improved. Therefore, the parachlorotoluene and the o-chlorotoluene are effectively separated.

The invention discloses a method for preparing p-chlorobenzaldehyde through selective oxidation of p-chlorotoluene, which comprises the following steps: in a stirring type reaction kettle, taking p-chlorotoluene or a mixture of p-chlorotoluene and p-chlorobenzaldehyde as a liquid-phase raw material, taking a variable-valence metal complex as a main catalyst, and taking chloride and / or iodide as a cocatalyst; introducing oxygen-containing gas to carry out oxidation reaction; the height-diameter ratio of the stirring type reaction kettle is (5-8): 1, and a stirring paddle and a porous sintering gas distributor are arranged in the stirring type reaction kettle; and the difference between the height-diameter ratio of the stirring type reaction kettle and the layer number of the stirring paddles is 2. By optimizing the reactor and the catalytic system, the reactant conversion rate and the p-chlorobenzaldehyde selectivity can be improved, the reaction temperature is greatly reduced, and the use of bromide is avoided.

The invention discloses a method for synthesizing o-chlorotoluene and parachlorotoluene through selective chlorination of toluene. The method comprises the following steps: adding tungstic acid and a tungstic acid active center phase distribution regulation and control aid into toluene, uniformly stirring, then adding a hydrochloric acid solution, dropwise adding hydrogen peroxide while stirring, and heating for reaction to obtain chlorotoluene. The tungstic acid active center phase distribution regulation auxiliary agent is an ion pair system formed by organic onium cations and strong acid stable anions; the organic onium cation is a quaternary phosphonium cation; and the strong acid stable anions are selected from hydrogen sulfate anions, phosphate anions or sulfonate anions. Tungstic acid is used as a catalyst, concentrated hydrochloric acid is used as a chlorine source, hydrogen peroxide is used as an oxidizing agent, and a tungstic acid active center phase distribution regulation auxiliary agent is used for realizing interphase dynamic exchange to carry out toluene chlorination reaction. According to the method, the conversion rate in the toluene chlorination reaction and the selectivity of chlorinated products can be improved, the waste hydrochloric acid can be applied in a green and efficient manner, the cost is effectively reduced, and the method is an important method beneficial to industrial production of chlorotoluene.

The present invention discloses a method for electrochemically synthesizing p-chlorobenzaldehyde, and the steps are as follows: 1) Prepare a tetrabutylammonium perchlorate acetonitrile solution, add p-chlorotoluene, and mix to obtain an electrolyte solution; 2) Add the electrolyte solution into the anode chamber of an H-type electrolytic cell, add an aqueous alkali solution into the cathode chamber of the H-type electrolytic cell, clamp a catalyst with an electrode clip and place it into the anode chamber, and place a platinum plate electrode into the cathode chamber to carry out a constant current electrolysis reaction; 3) Subject the liquid in the anode chamber after the reaction to reduced pressure distillation and recrystallization to obtain p-chlorobenzaldehyde. By controlling the electrode current, the present invention enables the reaction to proceed according to a predetermined target, avoids the use of strong oxidants and harsh conditions such as high temperature and high pressure, and reduces resource waste and environmental pollution. The method of the present invention is simple, has a short cycle, and is green and pollution-free; in an H-type electrolytic cell, an external DC power supply can achieve the electrochemical oxidation of p-chlorotoluene, and the reaction conditions are relatively mild with high catalytic activity.

The invention belongs to the technical field of sewage treatment equipment, and particularly relates to o (p) chlorotoluene production sewage synchronous treatment equipment which comprises a support, and an extraction mechanism is mounted in the middle of the support. Light and heavy phase solutions can be mixed through operation of the extraction mechanism, the purpose of preliminarily and uniformly mixing the mixed solution is achieved, the extraction mechanism drives the separation mechanism to synchronously operate, the mixed solution is impacted and disturbed through the fixed inclined struts distributed in the separation mechanism in a staggered mode, and the mixed solution is further uniformly mixed; the extraction mechanism drives the stirring mechanism to rotate in an accelerated manner in the direction opposite to the operation direction of the extraction mechanism through the cooperation of the separation mechanism and the linkage mechanism, solution hedging can be locally formed, a mixed solution is uniformly mixed again, the mixing uniformity of a light-phase solution and a heavy-phase solution is remarkably improved, the contact time of the two phases is prolonged, and the extraction efficiency is improved. The problem of low extraction efficiency caused by poor mixing effect of existing equipment is effectively solved.

The invention discloses a method for synthesizing m-chlorotoluene through heterogeneous catalytic isomerization, and the method has the advantages of stable and easy recovery of a catalyst, greenness, sustainability, high selectivity of the product m-chlorotoluene, and the like, and is a m-chlorotoluene synthesis method with a wide prospect. The method for synthesizing m-chlorotoluene through heterogeneous catalytic isomerization comprises the following steps: filling a fixed bed reaction constant-temperature area with a modified HZSM-5 molecular sieve, in an inert atmosphere, conveying a mixture of raw materials parachlorotoluene and a diluent to a fixed bed reactor through a constant-flow pump, preheating, and vaporizing; and carrying out catalytic isomerization reaction in a constant-temperature area of the fixed bed reactor, condensing, and collecting to obtain the product m-chlorotoluene.

This invention discloses a chlorotoluene chlorination reactor based on photochlorination, comprising a reactor body with a lid, several ultraviolet lamps arranged in a ring array between the reactor body and a quartz protective cover, a chlorine gas inlet distribution assembly located at the bottom of the reactor body, and a vortex stirring assembly located inside the reactor body. In this invention, the ultraviolet light source is uniformly irradiated into the reactor body when the ultraviolet lamps pass through the reflector strip, causing the chlorotoluene material to undergo a photochlorination reaction. The vortex ring at the bottom of the reactor body creates a vortex effect on the chlorotoluene material, causing the chlorotoluene material to rotate in the vortex. The stirring blades create a shearing force, ensuring that the chlorotoluene material is fully mixed and participates in the photochlorination reaction. The arc-shaped stirring blades allow the chlorotoluene material to flow and stir from the center to the periphery in the reactor body, further ensuring that the chlorotoluene material has sufficient contact with the ultraviolet light source and improving the efficiency of the photochlorination reaction.

The application discloses a method for synthesizing meta-chlorotoluene through heterogeneous catalytic isomerization, and has the advantages of stable catalyst, easy recovery, green sustainability, high selectivity of the product meta-chlorotoluene and the like, and is a method for synthesizing meta-chlorotoluene with wide prospects. The method comprises the following steps: filling modified HZSM-5 molecular sieve into a fixed bed reaction constant temperature area and placing the fixed bed reaction constant temperature area in an inert atmosphere, feeding a mixture of raw material p-chlorotoluene and a diluent into the fixed bed reactor through a constant flow pump for preheating and vaporization, and then performing catalytic isomerization reaction in the fixed bed reaction constant temperature area, and collecting the product meta-chlorotoluene after condensation.

Disclosed in the present invention are a manganese oxide loaded cobalt-chromium catalyst and a preparation method therefor, and the use of the catalyst in the selective catalytic oxidation of p-chlorotoluene to prepare p-chlorobenzaldehyde. The preparation steps comprise: weighing a certain amount of a manganese salt, weighing cobalt and chromium precursor metal salts according to the loading amount, dissolving them in deionized water, and stirring same to obtain a mixed solution. After the above substances are fully dissolved at a certain temperature, a certain amount of acid is added, and the mixture is continuously heated and stirred. After the reaction is finished, the solid mixture is filtered under suction and washed, then roasted to obtain the catalyst, and finally the catalyst is used for the catalytic oxidation of p-chlorotoluene to prepare p-chlorobenzaldehyde. The catalyst of the present invention has a relatively low preparation cost, is easy to recycle subsequently, and is environmentally friendly and pollution-free. Moreover, the reaction conditions are relatively mild, and both the reaction conversion rate and selectivity are greatly improved. It has a good industrialization prospect.

The invention belongs to the field of chemical purification, and relates to a method for preparing high-purity parachlorotoluene through current pulse-assisted continuous suspension melt crystallization, which is characterized in that current pulse with specific parameters is applied in the suspension melt crystallization process for assistance, and a pulse electric field effect and directional energy input are utilized, so that the crystallization induction period can be remarkably shortened, and the high-purity parachlorotoluene can be prepared. The crystallization time is shortened by 50%-95% compared with that of a traditional method, the purity, the yield and the particle size are improved, and finally pure parachlorotoluene with the purity larger than or equal to 99.9% is obtained. No additional solvent is needed in the whole process, and the method has the advantages of being high in controllability, low in energy consumption, high in efficiency, capable of achieving continuity and the like, and is a green and efficient melt crystallization strengthening technology.

The invention discloses a kind of energy-saving system of multiple-effect distillation integration with low-pressure drop rectifying tower, including parachlorine tower, adjacent chlorine tower, parachlorine tower is equipped with the first reboiler, and adjacent chlorine tower is equipped with the second reboiler;The middle part of parachlorine tower is respectively provided with the first feed opening, the second feed opening, parachlorine tower reactor is provided with discharge pipeline, and discharge pipeline is provided with heat exchanger, and feed pipeline is connected with the first feed opening through heat exchanger;Parachlorine tower top gas outlet is respectively connected with the reflux port of parachlorine tower, adjacent chlorine tower through the second reboiler;Adjacent chlorine tower is provided with the 3rd feed opening, the 4th feed opening, adjacent chlorine tower top gas outlet is connected with the first condenser, the second condenser in sequence, and the feed pipeline of adjacent chlorine tower is connected with the 3rd feed opening through the first condenser;Adjacent chlorine tower reactor discharge port is connected with the second feed opening of parachlorine tower.The present invention system effectively reduces the pressure drop of rectifying tower, realizes the low-energy consumption smart separation of mixed ortho / parachlorotoluene system.

The invention belongs to the technical field of electrochemistry and organic chemical synthesis, and particularly relates to a preparation method of p-methylsulfonyl benzaldehyde, which comprises the following two main steps: (1) converting p-chlorotoluene serving as a raw material into p-chlorobenzaldehyde through electrochemical and hydrolysis reaction; and (2) carrying out substitution and oxidation reaction on the obtained p-chlorobenzaldehyde to finally prepare the p-methylsulfonyl benzaldehyde. According to the method, an electrolytic tank reactor is adopted, the reaction time is controllable, the conversion rate is high, few byproducts are produced, operation is easy and convenient, the production efficiency is greatly improved, and the problems that in a traditional synthesis method, aftertreatment is difficult, and safety is low are effectively solved. The invention provides a green process for synthesizing p-methylsulfonyl benzaldehyde under efficient and safe conditions, and the method has a good industrial application prospect.