The present invention and embodiments thereof provide a process to separate ethylene products from impurities such as nitrogen, hydrogen, ethane, propane and isobutane without the need for distillation processes.

The present invention and embodiments thereof provide a process to separate ethylene products from impurities such as nitrogen, hydrogen, ethane, propane and isobutane without the need for distillation processes.

Disclosed is a process for recovering paraxylene in which a first simulated moving bed adsorption unit is used to produce two extract streams—one rich in paraxylene and a paraxylene-rich extract stream that is lean in ethylbenzene and an ethylbenzene-rich extract stream that is lean in paraxylene- and a paraxylene-depleted raffinate stream. A significant amount of the ethylbenzene is removed in the ethylbenzene-rich extract stream (at least enough to limit buildup in the isomerization loop), so the paraxylene-depleted raffinate stream may be isomerized in the liquid phase. Avoiding vapor phase isomerization saves energy and capital, as liquid phase isomerization requires less energy and capital than the vapor phase isomerization process due to the requirement of vaporizing the paraxylene-depleted stream and the use of hydrogen, which requires an energy and capital intensive hydrogen recycle loop.

A process is described for separating paraxylene from a multicomponent fluid mixture of C8 aromatics. A mixture of C8 aromatics is fed to a simulated moving-bed adsorptive apparatus. The location of the feed to the apparatus is moved at set intervals. The rate of flow of feed to the apparatus is varied during each interval to enhance the separation of paraxylene from the multicomponent mixture.

A process is described for separating paraxylene from a multicomponent fluid mixture of C8 aromatics. A mixture of C8 aromatics is fed to a simulated moving-bed adsorptive apparatus. The location of the feed to the apparatus is moved at set intervals. The rate of flow of feed to the apparatus is varied during each interval to enhance the separation of paraxylene from the multicomponent mixture.

A process is described for separating paraxylene from a multicomponent fluid mixture of C8 aromatics. A mixture of C8 aromatics is fed to a simulated moving-bed adsorptive apparatus. The location of the feed to the apparatus is moved at set intervals. The rate of flow of feed to the apparatus is varied during each interval to enhance the separation of paraxylene from the multicomponent mixture.

Methods of preparing and using a metal-organic framework (MOF) are provided herein, including methods of using an MOF comprising a repeat unit of the formula [ML].sub.n, wherein M is a divalent metal ion and L is a ligand of the formula: ##STR00001##
The MOFs provided herein may be used in the separation of two or more molecules from each other. In some embodiments, the molecules are ethylene and ethane. In some embodiments, UTSA-280 may be synthesized from calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) and squaric acid (SA) through mechanochemical synthesis.

Methods of preparing and using a metal-organic framework (MOF) are provided herein, including methods of using an MOF comprising a repeat unit of the formula [ML].sub.n, wherein M is a divalent metal ion and L is a ligand of the formula: ##STR00001##
The MOFs provided herein may be used in the separation of two or more molecules from each other. In some embodiments, the molecules are ethylene and ethane. In some embodiments, UTSA-280 may be synthesized from calcium oxide (CaO) or calcium hydroxide (Ca(OH).sub.2) and squaric acid (SA) through mechanochemical synthesis.

Described herein are compositions having an eight-membered monocyclic unsaturated hydrocarbon, methods and system to separate the eight-membered monocyclic unsaturated hydrocarbon at from a hydrocarbon mixture including additional nonlinear unsaturated C.sub.8H.sub.2m hydrocarbons with 4≤m≤8, by contacting the hydrocarbon mixture with a 10-ring pore molecular sieve having a sieving channel with a 10-ring sieving aperture with a minimum crystallographic free diameter greater than 3 Å and a ratio of the maximum crystallographic free diameter to the minimum crystallographic free diameter between 1 and 2, the molecular sieve having a T1/T2 ratio ≥20:1 wherein T1 is an element independently selected from Si and Ge, and T2 is an element independently selected from Al, B and Ga, the 10-ring pore molecular sieve further having a counterion selected from NH.sub.4.sup.+, Li.sup.+, Na.sup.+, K.sup.+ and Ca.sup.+.

Described herein are compositions having an eight-membered monocyclic unsaturated hydrocarbon, methods and system to separate the eight-membered monocyclic unsaturated hydrocarbon at from a hydrocarbon mixture including additional nonlinear unsaturated C.sub.8H.sub.2m hydrocarbons with 4≤m≤8, by contacting the hydrocarbon mixture with a 10-ring pore molecular sieve having a sieving channel with a 10-ring sieving aperture with a minimum crystallographic free diameter greater than 3 Å and a ratio of the maximum crystallographic free diameter to the minimum crystallographic free diameter between 1 and 2, the molecular sieve having a T1/T2 ratio ≥20:1 wherein T1 is an element independently selected from Si and Ge, and T2 is an element independently selected from Al, B and Ga, the 10-ring pore molecular sieve further having a counterion selected from NH.sub.4.sup.+, Li.sup.+, Na.sup.+, K.sup.+ and Ca.sup.+.