摘要:
A method is disclosed for using a pendulum viscometer having damped torsional oscillations, in a laboratory catalytic fluid-bed reactor, to monitor a propensity to stick which is exhibited by certain supported catalysts. A fluid-bed of such catalysts has been found to become suddenly more sticky just before a point at which a change in pressure drop across the fluid-bed can be measured due to a process "upset". At this point ("the inversion point"), the upset is usually irremediable. The method includes correlating data on catalyst stickiness from a laboratory reactor operating at atmospheric pressure, with an expected level of catalyst stickiness in a commercial reactor operating at elevated pressure.A pendulum viscometer and related auxiliary apparatus is disclosed for magnetically and electrically measuring and recording the rate at which the pendulum's torsional oscillations are damped. Frequent measurements are made during normal operation of the fluid-bed to determine its stickiness (as evidenced by the rate at which the pendulum's torsional oscillations are damped) relative to the stickiness at the inversion point. Operation of the fluid-bed under conditions for which measured rates of damping are predeterminedly lower than the rate near the inversion point, assures operation of the fluid-bed reactor at maximum efficiency.
摘要:
There is disclosed a method and composition for improving the fluidization characteristics and alleviating or inhibiting stickiness in a supported cupric chloride catalyst used as fluid bed catalyst in oxyhydrochlorinations reactions. The method involves the in situ preparation of the supported cupric chloride catalyst by addition of bare support on which no cupric chloride is deposited to the supported cupric chloride catalyst in the fluidized bed, or the use in the bed as the initial charge or as addition to the bed as makeup, of a composition which is a mixture of supported cupric chloride catalyst and bare support. In either event, as the oxyhydrochlorination proceeds, a portion of the cupric chloride on the supported catalyst becomes released therefrom and deposited in situ on the bare support, and stickiness of the cupric chloride containing catalyst particles to one another in the fluid bed is alleviated or inhibited.
摘要:
This process stems from the discovery that the solubility of water in vinyl chloride monomer ("VCM") is so low in a cold aqueous caustic solution at a temperature below 0.degree. C., that the aqueous solution will remove water dissolved in the monomer, and at the same time, will neutralize the HCl associated with the monomer and prevent the formation of acetylene. This discovery makes it possible to dry and neutralize a HCl and water-containing vinyl chloride ("VCl") stream, by intimately contacting the stream with a cold aqueous 2 to 30 wt % caustic soda solution at a temperature below 25.degree. F. and above the freezing point of the caustic solution. In a commercial VCM producing facility, VCl can be "finished" in a "stand-alone" processing facility with greater economy than in a conventional VCM plant, yet avoid the hazards of operating a conventional VCl stripping column and scrubbers packed with solid caustic pellets. The process allows simultaneously drying and neutralizing a VCl stream containing from about 1 part per million (ppm) to about 500 ppm HCl, and from about 10 ppm to about 300 ppm of water by contacting it with a 10% to 25% aqueous cold caustic solution, and separating dry and neutralized VCM monomer containing no more than 100 ppm water.
摘要:
The subject invention relates to a process for oxychlorination of ethylene to produce 1,2-dichloroethane. The process comprises contacting a mixture of ethylene, oxygen or oxygen containing gas and hydrogen chloride with a fixed or fluidized catalyst composition in a reaction zone and recovering 1,2-dichloroethane from the effluents of the reaction zone.The invention is embodied in a process for the oxychlorination of ethylene to produce 1,2-dichloroethane by contacting a mixture of ethylene, oxygen containing gas and hydrogen chloride with a catalyst composition in a reaction zone and recovering 1,2-dichloroethane from the effluents of the reaction zone the process comprising introducing ethylene, HCl and oxygen containing gas into said reaction zone in a ratio of 1.8 and 2.2 moles of HCl per mole of ethylene and from 0.5 to 1 mole of oxygen per mole of ethylene, the oxychlorination process taking place at a temperature of from 215.degree. C. to 230.degree. C., ethylene conversion on a weight basis is at 99% or higher and the mixture is contacted with a catalyst including a support which has deposited thereon a combination of metal chloride salts, the combination consisting essentially of from 2 to 8% copper, from 0.2 to 2% potassium and from 0.01 to 0.19% magnesium, all percentages expressed as the metals on a weight percent basis.
摘要:
Oxychlorination catalyst compositions which include a catalytically effective amount of an oxychlorination catalyst and a diluent having certain chemical composition and/or physical properties are disclosed. Processes using such oxychlorination catalyst compositions are also described. Some oxychlorination catalyst compositions and processes disclosed herein can increase the optimal operating temperature, and thereby increase the production capacity of an existing reactor, such as a fluid-bed reactor, compared to other oxychlorination catalyst compositions.
摘要:
A fluidizable catalyst composition is provided containing about 2% to about 8% by weight of copper (about 4% to about 17% by weight of copper salt), from about 1.0% to about 10% by weight of a rare earth metal salt(s), preferably the chloride salt(s), and from about 0.25% to about 2.3% by weight of an alkali metal salt(s), preferably the chloride salt(s), all weight percents based upon the total weight of the catalyst composition. The metals are codeposited on a fluidizable, high surface area alumina support. The weight of the alkali metal employed is not over 2.5% by weight (as the chloride) and the weight ratio of the rare earth metal salt(s) to the alkali metal salt(s) must be at least 1:1. Such catalyst compositions are extremely useful as fluid bed catalysts in the vapor phase oxychlorination reaction of ethylene, oxygen and hydrogen chloride to produce 1,2-dichloroethane (EDC). The use of the catalysts results in improved, high percent ethylene efficiencies and high percent HCl conversions, and avoids operating problems caused by stickiness of the catalyst in the fluid bed. A combination of copper chloride, potassium chloride and one or more of the rare earth chlorides on a fluidizable gamma alumina support, produces an excellent catalyst for a fluid bed ethylene oxychlorination process.
摘要:
The subject invention relates to catalyst compositions for oxychlorination of ethylene to produce 1,2-dichloroethane. The catalysts comprise copper chloride, at least one alkali metal, at least one rare earth metal, and at least one Group IIA metal on a high surface area support for fluid bed applications or on a high or low surface area support for fixed bed applications. The catalyst compositions are prepared by depositing the metals on a support. The use of the catalyst compositions of the invention in the oxychlorination of ethylene to EDC results in high percent ethylene efficiency, high EDC product purity and high percent HCl conversion without exhibiting catalyst stickiness. A process for oxychlorination of ethylene to produce 1,2-dichloroethane is also disclosed. The process relies on contacting a mixture of ethylene, oxygen or oxygen containing gas and hydrogen chloride with a fixed or fluidized catalyst composition in a reaction zone and recovering 1,2-dichloroethane from the effluents of the reaction zone.
摘要:
The subject invention relates to catalyst compositions for oxychlorination of ethylene to produce 1,2-dichloroethane. The catalysts comprise copper chloride, at least one alkali metal, at least one rare earth metal, and at least one Group IIA metal on a high surface area support for fluid bed applications or on a high or low surface area support for fixed bed applications. The catalyst compositions are prepared by depositing the metals on a support. The use of the catalyst compositions of the invention in the oxychlorination of ethylene to EDC results in high percent ethylene efficiency, high EDC product purity and high percent HCl conversion without exhibiting catalyst stickiness. A process for oxychlorination of ethylene to produce 1,2-dichloroethane is also disclosed. The process relies on contacting a mixture of ethylene, oxygen or oxygen containing gas and hydrogen chloride with a fixed or fluidized catalyst composition in a reaction zone and recovering 1,2-dichloroethane from the effluents of the reaction zone.
摘要:
In a process for producing 1,2-dichloroethane or ethylene dichloride ("EDC") in a high temperature direct chlorination ("HTDC") reactor in which ethylene is reacted with wet chlorine having a water content more than 100 ppm but no more than 1% by wt of the chlorine, the water leaves the reactor with the EDC product draw-off, either in the vapor overhead (if the HTDC is a boiling reactor), or, as a liquid sidestream (if the HTDC is a non-boiling reactor). In a subsequent step, the EDC draw-off is distilled in a product distillation column in which the water leaves in the overhead which is condensed to remove condensables in a first stage, and vent a non-condensable vent streams. The vent stream is corrosive due to the presence of minor amounts of chlorine, HCl and water, along with oxygen which is injected into the HTDC to improve selectivity of the reaction. The vent gases from the first stage are further cooled to a temperature in the range from about -30.degree. C. to about 0.degree. C. to condense condensables and freeze water without plugging the liquid lines. Plugging is avoided provided the vent stream contains less than 1.5% by wt of water, based on the weight of the vent stream. The essentially moisture-free non-condensables remaining are relatively non-corrosive and may be recycled to an oxychlorination reactor, also for the production of EDC, without unduly sacrificing the vent compressor and other carbon steel equipment in the recycle line.
摘要:
Oxychlorination catalyst compositions which include a catalytically effective amount of an oxychlorination catalyst and a diluent having certain chemical composition and/or physical properties are disclosed. Processes using such oxychlorination catalyst compositions are also described. Some oxychlorination catalyst compositions and processes disclosed herein can increase the optimal operating temperature, and thereby increase the production capacity of an existing reactor, such as a fluid-bed reactor, compared to other oxychlorination catalyst compositions.