Method for producing 1,2-dichloroethane
(57) Abstract:Usage: 1,2-dichloroethane is used as the solvent. Summary of the invention for producing 1,2-dichloroethane the process is conducted at a molar ratio of ethylene: chlorine 0,995 : 1,0 - 1,005 : 1,0, when the feed rate into the reactor chlorine containing 5,0 - 10,0% vol. oxygen, 300-900m3/h at a feed rate of ethylene 268-m3/h in the presence of 0.005 - 0.5 wt.% iron chloride (III) with 84 - 102°C and a pressure of 1,0105-1,8105and exhaust gases from the stage of selection of 1,2-dichloroethane condensation miss at 40 - 80°C in water of 1.0 - 5.0 wt. % solution of iron chloride (II), previously obtained by dissolving carbonate of iron (II) water of 3.0 - 10.0 wt.% the hydrochloric acid formed during the absorption of hydrogen chloride from the stage of purification of 1,2-dichloroethane raw. table 1. The invention relates to chemical technology, in particular to a method of producing 1,2-dichloroethane, which is used as intermediate for the synthesis of vinyl chloride or solvent in organic synthesis.The known method for producing 1,2-dichloroethane by oxychlorination process of ethylene using hydrogen chloride and air or oxygen with the addition of nitrogen at a temperature of 200-250o C 19/045, 17/156, publ. 1984).The disadvantage of this method is the complexity of the process, the use of elevated temperature and pressure, the presence in the exhaust from the reactor the gases carbon monoxide, cooling the effluent from the reactor a gas mixture of aqueous solutions of caustic soda.The known method for producing 1,2-dichloroethane by reacting ethylene and chlorine in the liquid phase at a temperature not lower than 83aboutIn the presence of a catalyst of iron chloride (III), an inhibitor of adverse reactions and oxygen, and released during the reaction heat is used to heat the cube columns for the separation of high-boiling components (see application Germany N 3604968, class C 07 C 19/045, published. 1986).According to a known method in the reactor filled with EDC serves ethylene, chlorine mixed with oxygen (0.1 to 10 mol.%).As catalyst, use iron chloride (III). In reaction medium is injected 0.001 to 0.1 wt.% inhibitors adverse reactions, which use benzene, cresol, their derivatives, amines, etc. are Formed a pair of 1,2-dichloroethane in contact with the fluid in the contact zone, enter the heat exchanger, which is the reboiler of the distillation column, and nscontainerframe the ilen reacts with additional input by chlorine, and containing in pairs 1,2-dichloroethane is condensed and subsequently the rectification 1,2-dichloroethane raw.The main disadvantage of this method is a multistage process. In addition, when disposing of ethylene some difficulties associated with the consumption control additional chlorine introduced into the second reactor, where it interacts excess of ethylene with chlorine.It should be noted that the subsequent disposal of gases containing chlorine, ethylene, hydrogen chloride, oxygen, greatly complicates the process for producing 1,2-dichloroethane.Closest to the invention to the technical essence and the achieved result is a method for producing 1,2-dichloroethane by chlorination of ethylene in the liquid phase in the presence of catalysts at a temperature of 90-160aboutC and a pressure of not less than 3 of 105PA, subsequent removal of catalysts, purification of 1,2-dichloroethane and gases (see application EPO N 113287, class C 07 C 19/045 17/02, publ. 1984).According to a known method chlorine containing 0.2 to 3.0 wt.% oxygen and ethylene, Inuktitut in reaction medium containing 1,2-dichloroethane and the catalyst. As the catalyst used Gladilina and chlorine (1,01-1,2):1, the speed of injection of ethylene over 10 m/s and feed rate of chlorine 1-100 m/C. the catalyst from the 1,2-dichloroethane is separated by washing with water or by distillation or by precipitation with calcium carbonate or calcium hydroxide, and 1,2-dichloroethane, not containing water and catalyst, is subjected to rectification in a system composed of multiple columns. Exhaust gases manufacture of 1,2-dichloroethane was subjected to purification.The main disadvantage of this method is the low quality of 1,2-dichloroethane raw, obtained in the production process (95,43-99,73 wt,%). A significant number of heavy chlorohydrocarbons (0.2-3.0 wt.% ) complicates the subsequent process of rectification of 1,2-dichloroethane and increases the cost of the target product.In addition, the process for producing 1,2-dichloroethane is carried out in an excess of ethylene in order to prevent leakage of chlorine through the reactor and the introduction of its exhaust gases in the exhaust. This leads to increased consumption of ethylene, as the exhaust gases after separation of 1,2-dichloroethane, or subjected to dispersion in air or incinerated.It should also be noted that the presence in the exhaust gases of the production of 1,2-dichloroethane ethylene mixed with oxygen and traces of chlorine increases pozarovzryvobezopasnost technologies water, containing hydrogen chloride, the remains of catalysts and other compounds, which are formed during the production of 1,2-dichloroethane.The aim of the invention is to improve the quality of 1,2-dichloroethane raw, the reduction of consumption of ethylene, reduced pozarovzryvobezopasnost process for producing 1,2-dichloroethane.This objective is achieved in that in the method for producing 1,2-dichloroethane by reacting ethylene with chlorine in the presence of oxygen and a catalyst - iron trichloride in liquid 1,2-dichloroethane at elevated temperature and pressure, the allocation of 1,2-dichloroethane condensation, purification of gases and 1,2-dichloroethane raw and subsequent rectification 1,2-dichloroethane, the process is carried out at a molar ratio of ethylene : chlorine 0,995:1,0-1,005: 1.0 at a feed rate of the chlorine into the reactor containing 5,0-10,0% vol. oxygen, 300-900 m3/h at a feed rate of ethylene 268-860 m3/h in the presence of 0.005-0.5 wt.% iron chloride (III) at a temperature of 84-102aboutAnd pressure 1,0105- 1,8105PA and the exhaust gases from the stage of selection of 1,2-dichloroethane condensation, miss at 40-80aboutThrough the water of 1.0-5.0 wt.% the solution of iron chloride (II), previously obtained by dissolving carbonate of iron (II) water of 3.0-10.0 wt.%-by the raw.The process for producing 1,2-dichloroethane at a molar ratio of ethylene: chlorine 0,995:1 - 1,005:1 in the scientific and patent literature are not described, which is associated with significant difficulties separating unreacted chlorine from gases generated upon receipt of 1,2-dichloroethane raw.The process for producing 1,2-dichloroethane at a molar ratio of ethylene : chlorine 0,995:1 - 1,005:1,0 allows to drastically reduce the consumption of ethylene in the production of 1,2-dichloroethane and reduce the ethylene content in the exhaust gases after the condensation of 1,2-dichloroethane to 1.0 vol.%. The content of chlorine and oxygen in the exhaust gases is not more than 0.001 and 5.0% vol. respectively.Use in a method of producing 1,2-dichloroethane chlorine containing 5,0-10,0% vol. oxygen, can dramatically reduce the formation of by-products and to improve the quality of 1,2-dichloroethane raw.Use in a method of producing 1,2-dichloroethane bandwidth gases after separation by condensation of 1,2-dichloroethane through the water of 1.0-5.0 wt.% the solution of iron chloride (II) at 40-80aboutWith in the scientific and patent literature are not described.Use in a method of producing 1,2-dichloroethane transmission of gases through an aqueous solution of chlorite is> significantly absorbed oxygen, hydrogen chloride and flue gases are not inflammable.An aqueous solution of iron chloride (II) is obtained by dissolution of carbonate of iron of 3.0-10.0 wt.% aqueous solution of hydrochloric acid, which is obtained by absorption of chloride Dorada after its separation from 1,2-dichloroethane raw cleanup phase.Thus, the technical solution as a new set of essential features showing new technical property meets the criterion of "substantial differences".The invention is illustrated by the following examples in which the above process parameters and properties of 1,2-dichloroethane raw and gases.P R I m e R 1 (invention). In charator, which is a vertical cylindrical apparatus of stainless steel 12X18H10T with six perforated grilles to prevent vertical mixing volume 22 m3download 12000 kg 1,2-dichloroethane raw and in the lower part of the reactor through separate pipelines serves ethylene speed 805 m3/h and a pressure of 1105PA and chlorine containing 10 vol.% oxygen, with a speed of 900 m3/h and a pressure of 1105PA.The molar soothes the e passage of the reaction between ethylene and chlorine, beginning in the mixing zone and terminating in the reaction zone, the reactor temperature is maintained at 84aboutC, and the excess heat released during the reaction is removed return 1,2-dichloroethane-raw, which enters the lower part of charator of gazorazdelitel after cooling and condensation of 1,2-dichloroethane from gases. Departing from charator gases are cooled in karabanovich refrigerators are cooled by a brine of sodium chloride with a temperature of 2-4aboutWith, and condensed 1,2-dichloroethane is separated from the gases in patristical and enters the lower part of charator. Exhaust gases with a temperature of less than 50aboutWith that contain traces of ethylene, chlorine, hydrogen chloride, neskondensirovannyh pair of 1,2-dichloroethane and light chlorohydrocarbons of gazorazdelitel arrive in the lower part of the titanium column length of 8 m and an inner diameter of 1400 mm, containing 6 plates, which are irrigated with a speed of 6-8 m2/h of aqueous 5 wt.% ferric chloride solution (II). At 60aboutSince the column is absorbed hydrogen chloride, and chlorine and oxygen is almost completely consumed in the process of redox reactions with ferric chloride (II), 1,2-dichloroethane and hydrogen chloride from the top of AB is 2-dichloroethane through patristical drained by gravity into the container, and a pair of 1,2-dichloroethane and hydrogen chloride arrive in igurative refrigerators, refrigerated brine with a temperature of -35aboutWith, for comensoli 1,2-dichloroethane. Exhaust gases from gazorazdelitel with temperature (0 to minus 20aboutWith come in refrigerators-absorbers, in which hydrogen chloride is absorbed by the circulating water.The resulting water of 0.5-1.5 wt.% the hydrochloric acid solution is circulated in a closed cycle to the content of HCl in a solution of 3.0-10.0 wt.% and then fed into the vessel containing the carbonate iron (II), formed by the dissolution of carbonate of iron chloride solution iron (II) with a concentration of 1.0-5.0 wt.% postupy speeds of 6-8 m3/h for irrigation titanium absorption columns.The content of 1,2-dichloroethane, 1,1,2-trichloroethane and other choreodrama hydrocarbons in 1,2-dichloroethane raw in the exhaust gases were estimated chromatographic according to GOST 1942-86 section 4.The oxygen content in the exhaust gases after absorption with an aqueous solution of iron chloride (II) was evaluated using coloradamar.The content of ethylene, chlorine in the exhaust gases at the inlet and outlet of the absorption column were evaluated by chromatographic (ethylene) and iodometric titration (chlorine).P R I m e R s 2-5 (izopet,2-dichloroethane raw and gases are summarized in table.P R I m e R s 6-10 (control). Synthesis of 1,2-dichloroethane carried out as in example 1. Download components, conditions of formation and properties of 1,2-dichloroethane raw and gases are summarized in table.As can be seen from the data summarized in the table, the process for producing 1,2-dichloroethane at a molar ratio of ethylene : chlorine in smaller proportions than claimed, leads to a significant content of molecular chlorine in the exhaust gases, which dramatically increases the amount of iron chloride (II) required for complete binding of chlorine.The process for producing 1,2-dichloroethane at the ratios of ethylene, chlorine, larger than claimed, leads to a significant waste of ethylene, utilization of gases associated with significant energy costs condensation or sigana gases. It also increases pozarovzryvobezopasnost process for producing 1,2-dichloroethane due to the presence in the exhaust gases of the significant content of ethylene.When carrying out process for producing 1,2-dichloroethane at temperatures lower than the boiling point of 1,2-dichloroethane, dramatically decreases the performance of charator.The temperature of the synthesis and the pressure in chloretone due to the fact, when using aqueous solutions of ferric chloride (II) with a concentration of less than 1.0 wt.%, not achieved full binding molecular chlorine and capture the necessary oxygen, which reduces the efficiency of cleaning gases (see example 8).The use of more concentrated solutions of iron chloride (II) than claimed, was not feasible due to hydrolysis of ferric chloride (III), and selection process of absorption of insoluble oxychloride iron.Carrying out the absorption of gases at temperatures less than 40about(See example 10) does not ensure the full removal of the gases of chlorine and oxygen due to the low rate of oxidation of iron chloride (II).Carrying out the absorption of gases by iron chloride (II) at temperatures exceeding 80aboutSince it is impractical because of the emergence of a significant amount of insoluble oxychlorides and oxides of iron (III), which complicates the process.Thus, the proposed method for producing 1,2-dichloroethane in comparison with the prototype has the following advantages:
allows you to improve the quality of 1,2-dichloroethane raw at the expense of education in the process of reaction of 1,1,2-trichloroethane;
reduces consumption rates of ethylene in obtaining 1,2-dichloroethane;
reduces pozarovzryvobezopasnost processed economy of the process.Conditions for producing 1,2-dichloroethane, its properties and the properties of gases shown in the table. METHOD for producing 1,2-DICHLOROETHANE by reacting ethylene with chlorine in the presence of oxygen and a catalyst - iron trichloride in liquid 1,2-dichloroethane at elevated temperature and pressure, the allocation of 1,2-dichloroethane condensation, purification of gases and 1,2-dichloroethane raw and subsequent rectification 1,2-dichloroethane, characterized in that the goal of improving the quality of 1,2-dichloroethane and reduce pozarovzryvobezopasnost process, the process is carried out at a molar ratio of ethylene : chlorine 0,995 - 1,005 : 1.0 at a feed rate of the chlorine into the reactor containing 5 - 10% vol. oxygen, 300 - 900 m3/h at a feed rate of ethylene 268 - 860 m3/h in the presence of 0.005 - 0.5 wt. % iron chloride (III) with 84 - 102oWith and (1,0 - 1,8) 105PA and the exhaust gases from the stage of selection of 1,2-dichloroethane condensation miss at 40 - 80oWith water through 1 - 5% solution of iron chloride (II).
FIELD: gas treatment.
SUBSTANCE: invention is intended for fine purification of gases with removal of carbon dioxide at elevated pressures, in particular in hydrogen or ammonia production processes. Absorbent is an aqueous solution containing N-methyldiethanolamine, piperazine, potassium carbonate, and morpholine. Invention achieves reduced equilibrium pressure and increased carbon dioxide absorption at low degrees of carbonization (as low as 0.1 mole CO2 per mole tertiary amine) without appreciable N-methyldiethanolamine degradation rate.
EFFECT: enhanced carbon dioxide absorption efficiency.
2 dwg, 6 tbl, 2 ex
FIELD: gas treatment.
SUBSTANCE: invention is directed to remove hydrogen sulfide from CO2-containing process gases from enterprises involving heat treatment of sulfur-containing combustible fossils in reductive medium. Treatment comprises countercurrent contact of gases with liquid basic absorbent, absorption of hydrogen sulfide with absorbent, separating hydrogen sulfide from associated carbon dioxide, and converting hydrogen sulfide into usable products. Absorbent is selected from aqueous solutions or suspensions of alkali and alkali-earth metal hydroxides and oxides. Contact of gas with absorbent is performed in vortex chambers provided with rotating gas-liquid layer at residence from 0.001 to 0.1 sec.
EFFECT: increased degree of purification of gases and simplified treatment scheme.
1 dwg, 5 ex
FIELD: gas treatment.
SUBSTANCE: invention relates to compositions for oxidative removal of hydrogen sulfide from gases to produce elementary sulfur, which compositions can be used in oil and gas production, petroleum and gas processing, chemical, and other industries. Absorbent contains, g/L: iron chelate compound (on conversion to ferric ion) 2-12, alkali metal phosphate (on conversion to phosphate anion) 1-16, alkali metal carbonate or hydroxide 1-60, methyldiethanolamine and/or triethanolamine 10-30, monoethanolamine/formaldehyde reaction product 0.2-10, and water to 1 L. Monoethanolamine interacts with 37% formaldehyde solution at molar ratio 1:(1-3). Iron chelate compound is a complex of ferric compound with ethylenediaminetetraacetic acid disodium salt. To reduce foaming, absorbent may further contain 0.05-0.2 g/L aluminum sulfate.
EFFECT: increased stability and decreased corrosive activity of absorbent without loss in its high absorbing capacity regarding hydrogen sulfide.
4 cl, 2 tbl, 5 ex
FIELD: petroleum and gas and other industries; glycol regeneration installations.
SUBSTANCE: the invention is dealt with installations of glycol regeneration with use of vacuum, which may find application in processes of a hydrocarbon gas absorptive drying from a moisture. The invention may be used in gas, petroleum and other industries. The installation includes a saturated glycol feeding pipeline connected through an ejector to an atmospheric column - stripper, which has an outlet branch-pipe of partially regenerated glycol and is fused to the vacuum column supplied with the lower branch-pipe of regenerated glycol withdrawal and the upper branch-pipe of vapors withdrawal, which are linked to a passive nozzle of the ejector. At that the saturated glycol feeding pipeline has a section with two parallel lines, on one of which there is the ejector with a flow meter mounted in front of its active nozzle and connected with a control valve installed on one of the lines. The vacuum column is made in the form of mass-exchange column and equipped with a fixed plate with a located over it branch-pipe of withdrawal of water, a cooling coil in the column upper part and a contact device with low hydraulic resistance in the lower part. The invention ensures efficient regeneration of glycol in the vacuum column and unloading of an atmospheric column - stripper.
EFFECT: the invention ensures efficient regeneration of glycol in the vacuum column and unloading of an atmospheric column - stripper.
3 cl, 1 dwg
FIELD: waste treatment.
SUBSTANCE: invention relates to processing of toxic industrial wastes, more specifically to the process of detoxification of plant-protection chemicals with exceeded storage time or prohibited to use. Utilization of combustion gases consists in passing them through a bed of inorganic metal compound melt disposed in reactor in presence of gaseous oxidant, said inorganic metal compound being a mixture of alkali hydroxides. Gaseous oxidant preliminarily used in excess of at least 3 vol % on the total volume of emission gases is sent to the melt together with emission gases. The latter are introduced from below in such a manner as to assure their contact time with melt at least 2 sec, whereas bed of melt is extended to 0.5-0.8 reactor height.
EFFECT: achieved fullness in trapping toxic components and improved environmental condition.
FIELD: chemical refining of waste gasses.
SUBSTANCE: the invention is dealt with a method of purification of waste gasses of heating and power stations from carbon dioxide by introduction in the waste gas stream of products of incineration of hydrocarbon fuel of an alkaline solution. At that the alkaline solution is fed in a dispersed form into the upstream of the waste gasses moving in a turbulent mode in the space of the stalk of the heating and power station. In the capacity of the alkaline solution they use circulating water of ash removal of the heating and power station. A dispersed alkaline solution is fed into the base part of the stalk of the heating and power station. Before use of the circulating water of ash removal increase its alkalinity by mixing it with the ash from consequent separation of the solution and the ash residue by settling and filtration. At that alkali is extracted from ash into the water. The invention ensures increased completeness and speed of interaction of the components at the expense of use of energy of the purified stream of the waste gasses.
EFFECT: the invention ensures increased completeness and speed of interaction of the components due to use of energy of the purified stream of the waste gasses.
FIELD: petrochemical and chemical industry; purification of gas mixtures from carbon dioxide.
SUBSTANCE: the invention is pertaining to the field of purification of gas mixtures from carbon dioxide. Absorption is conducted using wipers with resistance by a gas of no more than 50 kPa. At that a solution of ethanolamine in the process of the absorption at least once is subjected to intercooling to 30-35°C. Fine regeneration of a stream of a solution of ethanolamine is realized by its treatment with machining by a live steam. The absorber is made with packet-type nozzles and contains in its middle part at least one contour of cooling made in the form of a device of withdrawal of a partially saturated solution of the absorbent cyclically linked with an intermediate container and an intermediate cooler. A hot-water boiler of the regenerator-recuperator is made in the form of the sections in series located in its lower part. The sections are consisting of heat exchangers placed on plates. At that the number of the sections of the hot-water boiler is chosen within the limits from three to six. In the double-flow circuit the outlet of the roughly regenerated absorbent is made in the form of an outlet of the blank plate located under the hot-water boiler. The regenerator-recuperator in its lower part above an outlet of the finely regenerated absorbent is supplied with an inlet of the steam feeding and with three or four steaming plates located above it. The invention allows to reduce an over-all excessive pressure of the process of purification of gas mixtures from carbon dioxide and its partial pressure, to reduce specific power inputs for purification and also to expand the field of application of the ethanolamine purification.
EFFECT: the invention allows to reduce the over-all excessive and partial pressure of the process of gas mixtures purification from carbon dioxide and to expand the field of the ethanolamine purification application.
12 cl, 7 ex, 3 dwg
FIELD: heat-power engineering; cleaning flue gases from toxic admixtures.
SUBSTANCE: proposed method includes cooling of flue gases to temperature below dew point, condensation of water vapor, mixing of cooled flue gases with ozone-and-air mixture, oxidation and absorption of nitrogen oxides and sulfur oxides by condensate thus obtained and discharge of cleaned flue gases and condensate from zone of treatment. Flue gases and acid condensate are cleaned from carbon dioxide in perforated units of cassettes coated with layer of slaked lime [Ca(OH02] for forming calcium nitrite [Ca(NO3)], calcium carbonate (CaCO3) and calcium nitrate [Ca(NO3)]. Device proposed for realization of this method includes zone of treatment in form of box with heat-exchange and absorption-and-heat exchange sections located in this box in way of motion of flue gases. These sections are provided with air and flue gas inlet and outlet branch pipes where heat exchangers-air preheaters of 1st and 2nd stages, horizontal and vertical perforated cassettes units made from rough corrosion-resistant material coated with layer of slaked lime [Ca(OH2)], mixing chamber with perforated distributing tube and air duct with ozonizer are located.
EFFECT: enhanced ecological and economical efficiency and reliability.
3 cl, 1 dwg
FIELD: oil production; trapping hydrocarbons in slow coking plants.
SUBSTANCE: proposed plant includes reservoir for receiving the products heating the coking reactors with piping system equipped with pumps discharging non-conditioned oil products and pipe lines discharging gas for rectification or sprinkling into scrubber for steaming and cooling the coke at discharge of gas into atmosphere and drainage of water condensate into disposal system through hydraulic seal; hydraulic seal is connected via vibrating sieve with near-reactor coke accumulator combined with gravity filter; above-sieve part of vibrating sieve is connected with near-reactor coke accumulator and under-sieve part is connected via gravity filter with deepened circulating water reservoir or with disposal system. Proposed plant makes it possible to return some components of water condensate and cool coke at simultaneous discharge of them to disposal system.
EFFECT: improved quality of separation of steaming products.
3 cl, 1 dwg
FIELD: heat technology.
SUBSTANCE: invention relates to technology for treatment of smoke gases from sulfur dioxide. Method for treatment of smoke gases from sulfur dioxide involves passing smoke gases through countercurrent scrubber with absorption liquid based on ammonia aqueous solution for preparing ammonium sulfite followed by oxidation of ammonium sulfite to ammonium sulfate. Then one part of absorption solution removing after oxidation is mixed with fresh ammonium aqueous solution and fed to treatment of smoke gases and another part is fed to utilization. Oxidation is carried out with smoke gases oxygen in indicated scrubber in addition initiating agent for oxidation to absorption liquid as azocompounds. Invention provides simplifying the process and to reduce time for accumulation of ammonium sulfite by 1.8-2.0-fold.
EFFECT: improved method for treatment.