A dehydrochlorination process is disclosed. The process involves contacting R.sub.fCHClCH.sub.2Cl with a chromium oxyfluoride catalyst in a reaction zone to produce a product mixture comprising R.sub.fCCl═CH.sub.2, wherein R.sub.f is a perfluorinated alkyl group.

A method for activating a chromia-based catalyst for fluorination and/or hydrofluorination comprises the steps of: a) optionally drying the catalyst at a temperature of from 100° C. to 400° C.; b) treating the catalyst with a composition comprising HF at a temperature of from 100° C. to about 500° C.; c) treating the catalyst with a composition comprising an oxidant and optionally HF at a temperature of from about 100° C. to about 500° C.

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with hydrogen gas, an unsaturated hydrocarbon, and/or a saturated hydrocarbon to form products.

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with hydrogen gas, an unsaturated hydrocarbon, and/or a saturated hydrocarbon to form products.

The present invention aims to provide an efficient method for obtaining a desired isomer of HFO-1132 from a composition comprising trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)).

The present invention provides, as a means for solving the problem, a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising steps (1) to (3): (1) supplying a composition comprising HFO-1132(E) and/or HFO-1132(Z) to a reactor filled with a catalyst to perform an isomerization reaction between the HFO-1132(E) and the HFO-1132(Z); (2) separating the reaction product obtained in step (1) into a first stream comprising the HFO-1132(E) as a main component, and a second stream comprising the HFO-1132(Z) as a main component; and (3) recycling the first stream or the second stream obtained in step (2) to the reactor, to subject the first stream or the second stream to the isomerization reaction.

The present invention aims to provide an efficient method for obtaining a desired isomer of HFO-1132 from a composition comprising trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)).

The present invention provides, as a means for solving the problem, a method for producing HFO-1132(E) and/or HFO-1132(Z), comprising steps (1) to (3): (1) supplying a composition comprising HFO-1132(E) and/or HFO-1132(Z) to a reactor filled with a catalyst to perform an isomerization reaction between the HFO-1132(E) and the HFO-1132(Z); (2) separating the reaction product obtained in step (1) into a first stream comprising the HFO-1132(E) as a main component, and a second stream comprising the HFO-1132(Z) as a main component; and (3) recycling the first stream or the second stream obtained in step (2) to the reactor, to subject the first stream or the second stream to the isomerization reaction.

A catalyst for producing light aromatics with heavy aromatics, a method for preparing the catalyst, and a use thereof are disclosed. The catalyst comprises a carrier, component (1), and component (2), wherein component (1) comprises one metal element or more metal elements selected from a group consisting of Pt, Pd, Ir, and Rh, and component (2) comprises one metal element or more metal elements selected from a group consisting of IA group, IIA group, IIIA group, IVA group, IB group, IIB group, IIIB group, IVB group, VB group, VIB group, VIIB group, La group, and VIII group other than Pt, Pd, Ir, and Rh. The catalyst can be used for producing light aromatics with heavy aromatics, whereby heavy aromatics hydrogenation selectivity and light aromatics yield can be improved.

Disclosed is a method for co-producing 2,3,3,3-tetrafluoropropene and trans-1,3,3,3-tetrafluoropropene, comprising the following steps: preheating a mixture of 1,1,1,2,2-pentachloropropane and 1,1,1,3,3-pentachloropropane together with anhydrous hydrogen fluoride and simultaneously introducing into a first reactor to react in the presence of a catalyst La.sub.2O.sub.3—Cr.sub.2O.sub.3 to obtain a first reactor product; directly introducing the first reactor product into a second reactor without separation, and carrying out a catalytic fluorination reaction in the presence of a catalyst Ga.sub.2O.sub.3—Y.sub.2O.sub.3—Cr.sub.2O.sub.3 to obtain a second reactor product; and separating the second reactor product to obtain the products of 2,3,3,3-tetrafluoropropene and trans-1,3,3,3-tetrafluoropropene. The invention has such advantages that the process is simple and less equipment investment is required; used catalysts have good activity, high selectivity and long total life; and the ratio of the two products can be flexibly adjusted according to market demands.

The invention relates to a method for preparation of diesters from anhydrides of carboxylic acids.

The invention relates to a method for preparation of diesters from anhydrides of carboxylic acids.