Organosilicon Lewis acids supported on activated oxides and metal oxo complexes grafted on the organosilicon Lewis acids as heterogeneous catalysts and the related compositions, methods and systems are described. These organosilicon Lewis acids and the grafted metal oxo complexes catalyze industrially important chemical reactions including, respectively, C—F bond activation and olefin metathesis reactions such as homocoupling and polymerizations.

The present disclosure provides natural gas and petrochemical processing systems, including oxidative coupling of methane reactor systems that may integrate process inputs and outputs to cooperatively utilize different inputs and outputs in the production of higher hydrocarbons from natural gas and other hydrocarbon feedstocks. The present disclosure also provides apparatuses and methods for heat exchange, such as an apparatus that can perform boiling and steam super-heating in separate chambers in order to reach a target outlet temperature that is relatively constant as the apparatus becomes fouled. A system of the present disclosure may include an oxidative coupling of methane (OCM) subsystem that generates a product stream comprising compounds with two or more carbon atoms, and a dual compartment heat exchanger downstream of, and fluidically coupled to, the OCM subsystem.

The present disclosure provides natural gas and petrochemical processing systems, including oxidative coupling of methane reactor systems that may integrate process inputs and outputs to cooperatively utilize different inputs and outputs in the production of higher hydrocarbons from natural gas and other hydrocarbon feedstocks. The present disclosure also provides apparatuses and methods for heat exchange, such as an apparatus that can perform boiling and steam super-heating in separate chambers in order to reach a target outlet temperature that is relatively constant as the apparatus becomes fouled. A system of the present disclosure may include an oxidative coupling of methane (OCM) subsystem that generates a product stream comprising compounds with two or more carbon atoms, and a dual compartment heat exchanger downstream of, and fluidically coupled to, the OCM subsystem.

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).

A method for selectively hydrogenating acetylene in a cracked gas from a steam cracking unit for producing olefins may include separating a hydrogenation feed from the cracked gas. The hydrogenation feed may include acetylene, hydrogen, carbon monoxide, and at least one product. The method may further include contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent. In response to a change in a composition of a feedstock to the steam cracking unit that results in a change in a hydrogen concentration in the hydrogenation feed, the method may further include determining the hydrogen concentration in the hydrogenation feed and increasing or decreasing a temperature of the hydrogenation feed based on the determined hydrogen concentration of the hydrogenation feed.

A method for selectively hydrogenating acetylene in a cracked gas from a steam cracking unit for producing olefins may include separating a hydrogenation feed from the cracked gas. The hydrogenation feed may include acetylene, hydrogen, carbon monoxide, and at least one product. The method may further include contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent. In response to a change in a composition of a feedstock to the steam cracking unit that results in a change in a hydrogen concentration in the hydrogenation feed, the method may further include determining the hydrogen concentration in the hydrogenation feed and increasing or decreasing a temperature of the hydrogenation feed based on the determined hydrogen concentration of the hydrogenation feed.

In a first stage of a methane conversion system, at least some methane (CH.sub.4) in an input gas flow stream can be converted into C.sub.2 hydrocarbons, hydrogen gas (H.sub.2), and aromatics to provide a first processed stream. The conversion can be direct non-oxidative methane conversion (DNMC). At least some of the aromatics can be removed from the first processed stream to provide a second processed stream. In a second stage of the methane conversion system, at least some of the H.sub.2 can be removed from the second processed stream to provide a recycle stream. The recycle stream can be returned to the first stage of the methane conversion system for further conversion of methane and removal of aromatics and H.sub.2 products.

In a first stage of a methane conversion system, at least some methane (CH.sub.4) in an input gas flow stream can be converted into C.sub.2 hydrocarbons, hydrogen gas (H.sub.2), and aromatics to provide a first processed stream. The conversion can be direct non-oxidative methane conversion (DNMC). At least some of the aromatics can be removed from the first processed stream to provide a second processed stream. In a second stage of the methane conversion system, at least some of the H.sub.2 can be removed from the second processed stream to provide a recycle stream. The recycle stream can be returned to the first stage of the methane conversion system for further conversion of methane and removal of aromatics and H.sub.2 products.

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).