Disclosed is a process for the preparation of 3,3,3-trifluoropropene comprising the steps of; (1) fluorination of 240fa to form 245fa; (2) conversion of 245fa to a cis/trans mixture of 1234ze; (3) hydrogenation of the cis/trans mixture of 1234ze to form 254fb; and (4) dehydrofluorination of 254fb to produce 3,3,3-trifluoropropene. Alternatively or additionally, a second process for the preparation of the desired compound comprises the following steps; (1) fluorination of HCC-240fa to form HCFC-244fa; (2) conversion of 244fa to a cis/trans mixture of HFO-1234ze; (3) hydrogenation of the cis/trans mixture of 1234ze to form HFC-254fb; and (4) dehydrofluorination of 254fb to produce 3,3,3-trifluoropropene.

Methods to produce 3,3,3-trifluoropropene

The invention discloses a method for catalytic degradation of hexachlorobenzene. The method comprises the following steps: firstly, filling a catalyst into a fixed bed reactor, and carrying out reduction treatment on the catalyst; secondly, mixing hexachlorobenzene steam and preheated hydrogen uniformly to obtain a mixed gas, introducing the mixed gas into the fixed bed reactor after reduction treatment, and carrying out catalytic hydrodechlorination reaction on the catalyst, thereby obtaining the mixed gas of benzene steam, hydrogen chloride gas and unreacted hydrogen; and thirdly, feeding the mixed gas of benzene steam, hydrogen chloride gas and unreacted hydrogen into a condenser for condensing, converting benzene into liquid, then feeding the hydrogen chloride gas and unreacted hydrogen in the mixed gas into an absorption tower for absorbing hydrogen chloride by ammonia water, compressing the unreacted hydrogen by a compressor, and returning for recycling. A solvent is not required to be added in catalytic hydrogenation and degradation of hexachlorobenzene by the method provided by the invention, benzene and ammonium chloride are produced as byproducts, and zero emission of pollutants can be reached, and the method is an environmental-friendly technology for degrading hexachlorobenzene efficiently.

Method for catalytic degradation of hexachlorobenzene

The invention discloses a catalyst for synthesizing 2-3,3,3-tetrafluoropropene from 2-chloro-3,3,3-trifluoropropene and a preparation method thereof. The catalyst consists of fluorides of Cr, Zn and M, wherein M is one or two of Mg and Ni; the molar ratio of Cr to Zn to M is 1: (0.05-0.1): (0.02-0.05). The preparation method comprises the following steps: adding a KOH alkaline solution in a Cr compound, a Zn compound and an M compound which are proportional so as to form precipitates, or carrying out mechanical blending on the three compounds to form a blend; adding a saccharose-citric acid solution in a mixture obtained from the former step, wherein in the saccharose-citric acid solution, the molar ratio of saccharose to citric acid is 1:1; after fully mixing, drying and roasting in N2 atmosphere to obtain oxide containing a carbon template agent; and treating the oxide precursor containing the carbon template agent with inert gas and anhydrous hydrogen fluoride, and then oxidizing in an oxygen atmosphere to remove the carbon template agent to obtain the catalyst.

Catalyst for synthesizing 2-3,3,3-tetrafluoropropene from 2-chloro-3,3,3-trifluoropropene and preparation method thereof

The present invention discloses a pentafluoroethane purification method, which comprises: (a) preparing a reaction device; (b) carrying out extracting rectification; (c) carrying out distillation purification; and (d) using a by-product. According to the present invention, the method has advantages of simple process and easy control; the method sequentially comprising extracting rectification and distillation is used, such that the separation efficiency is high, the crude product is effectively separated, the purity of the separated finished product pentafluoroethane can achieve more than 99.9%, the purity is high, and the quality is good; and the separated by-product chloropentafluoroethane is recycled, and is converted into the product pentafluoroethane so as to improve the utilization rate of the by-product and turn the waste into treasure.

Pentafluoroethane purification method

The invention discloses a membrane catalyst, a precursor and a carrier of the membrane catalyst as well as a preparation method of the membrane catalyst, wherein the preparation method of the precursor comprises the following steps: dropwise adding an acid solvent slowly into an absolute ethanol solution, stirring evenly, controlling a pH value to be 6.5-7.5, adding aluminum isopropoxide in partsper 100 parts of mass of aluminum, then adding 0.5-5 parts of metal additive salt in parts by mass of metal, and refluxing for 8-15 h in thermostatic waterbath at 50- 70 DEG C to obtain composite sol,putting porous ceramic in the composite sol to dip, dipping repeatedly a plurality of times, and then drying and roasting to prepare the precursor of the membrane catalyst. According to the embodiment of the invention, the membrane catalyst with an increased specific surface area is prepared by using an aluminum fluoride carrier membrane layer, loaded with Pd, with a relatively large specific surface area, so that the activity of the catalyst is improved, and meanwhile, by adding the metal additive, the selectivity and service life of the catalyst are increased, thereby reducing the use costof the catalyst.

Membrane catalyst, precursor and carrier of membrane catalyst as well as preparation method of membrane catalyst

The invention relates to a method for preparing a high-efficiency Pd/AlF3 catalytic agent used for directionally converting CFC-115 into HFC-125 by hydrogenation and dechlorination. In the invention, noble metal Pd is taken as an active component and self-made AlF3 powder with high specific surface area is taken as a carrier to prepare a load type Pd/AlF3 catalytic agent by adopting an immersion method. The Pd/AlF3 catalytic agent prepared by the method shows high catalytic activity on the reaction of generating HFC-125 by hydrogenating and dechlorinating CFC-115, and the selectivity of the target product is 100 percent.

Preparation and application of catalytic agent used for directionally converting CFC-115 into HFC-125 by hydrogenation and dechlorination

The invention discloses a method for synthesizing 3, 3, 3-trifluoro propene. The method is as follows: 1, 1, 1, 3-tetrachloropropane, catalyst and hydrofluoric acid are added in a high-pressure reactor used for deoxidization and dewatering, and are heated to a temperature of between 90 and 500 DEG C so as to carry out reaction for 0.5 to 3 hours, thereby obtaining 3, 3, 3-trifluoro propene product; moreover, the molar ratio between hydrofluoric acid and 1, 1, 1, 3-tetrachloropropane is between 3:1 and 300:1, and the mass ratio between catalyst and 1, 1, 1, 3-tetrachloropropane is between 0.005:1 and 10:1. The method can synthesize 3, 3, 3-trifluoro propene at high transformation efficiency and high selectivity with both the transformation efficiency and the selectivity reaching to more than 98 percent. Moreover, the method has the advantages of simple production equipment, short technological flow, long service life of catalyst, low price, high reaction transformation efficiency, ideal reaction selectivity and high product purity, etc.

Method for synthesizing 3,3,3-trifluoro propene

The invention discloses a method for the catalytic hydrodechlorination of CFC125 into HFC-125 Under optimized reaction conditions, the method can lead the conversion rate of the CFC-115 to over 90% and simultaneously maintain the selectivity of the HFC-125 over 95% The method for the catalytic hydrodechlorination of CFC125 into OFD-substitutes HFC-125 has great industrial application prospect

Method for catalytic hydrodechlorination of CFC125 into HFC-125

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Preparation and application of catalytic agent used for directionally converting CFC-115 into HFC-125 by hydrogenation and dechlorination

Method for synthesizing 3,3,3-trifluoro propene

Method for catalytic hydrodechlorination of CFC125 into HFC-125