Systems and methods are provided for hydrogenation of CO.sub.2 in a reverse flow reactor environment via a reverse water gas shift reaction. A reverse flow reactor environment is suitable for performing endothermic reactions at high temperatures, where a reactant flow is passed into the reactor in a first portion of the cycle in a first flow direction while a combustion or heating flow is passed into the reactor during a second portion of the reaction cycle from the opposite direction. This can allow for efficient heating of surfaces within the reactor to provide heat for the endothermic reverse water gas shift reaction while reducing or minimizing incorporation of combustion products into the desired reaction products.

A supercritical water oxidation vortex reactor has a reactor shell configured to contain a pressurized and heated material including water, a burner assembly configured to create a supercritical core region in the material in the reactor shell, the supercritical core region including water above its critical point, an injector assembly configured to inject into the enclosed volume a subcritical wash stream including water below its critical point and an aspirator arranged in the enclosed volume and configured to remove a processed flow including purified water from an upper portion of the supercritical core region. The supercritical water oxidation vortex reactor is configured with an upward helical flow to transfer precipitated ionic compounds out of the supercritical core region, through a transcritical intermediate region, and into the subcritical wash stream where they re-dissolve.

Supported chromium catalysts containing a solid oxide and 0.1 to 15 wt. % chromium, in which the solid oxide or the supported chromium catalyst has a particle size span from 0.5 to 1.4, less than 3 wt. % has a particle size greater than 100 μm, and less than 10 wt. % has a particle size less than 10 μm, can be contacted with an olefin monomer in a loop slurry reactor to produce an olefin polymer. Representative ethylene-based polymers produced using the chromium catalysts have a HLMI of 4 to 70 g/10 min, a density from 0.93 to 0.96 g/cm.sup.3, from 150 to 680 ppm solid oxide (such as silica), from 1.5 to 6.8 ppm chromium, and a film gel count of less than 15 catalyst particle gels per ft.sup.2 of 25 micron thick film and/or a gel count of less than or equal to 50 catalyst particles of greater than 100 μm per five grams of the ethylene polymer.

A first embodiment which is a bimodal polymer having a weight fraction of a lower molecular weight (LMW) component ranging from about 0.25 to about 0.45, a weight fraction of a higher molecular weight (HMW) component ranging from about 0.55 to about 0.75 and a density of from about 0.931 g/cc to about 0.955 g/cc which when tested in accordance with ASTM D1003 using a 1 mil test specimen displays a haze characterized by equation: % Haze=2145−2216*Fraction.sub.LMW−181*a molecular weight distribution of the LMW component (MWD.sub.LMW)−932*a molecular weight distribution of the HMW component (MWD.sub.HMW)+27*(Fraction.sub.LMW*MWD.sub.LMW)+1019*(Fraction.sub.LMW*MWD.sub.HMW)+73*(MWD.sub.LMW*MWD.sub.HMW) wherein fraction refers to the weight fraction of the component in the polymer as a whole.

Supported chromium catalysts containing a solid oxide and 0.1 to 15 wt. % chromium, in which the solid oxide or the supported chromium catalyst has a particle size span from 0.5 to 1.4, less than 3 wt. % has a particle size greater than 100 μm, and less than 10 wt. % has a particle size less than 10 μm, can be contacted with an olefin monomer in a loop slurry reactor to produce an olefin polymer. Representative ethylene-based polymers produced using the chromium catalysts have a HLMI of 4 to 70 g/10 min, a density from 0.93 to 0.96 g/cm.sup.3, from 150 to 680 ppm solid oxide (such as silica), from 1.5 to 6.8 ppm chromium, and a film gel count of less than 15 catalyst particle gels per ft.sup.2 of 25 micron thick film and/or a gel count of less than or equal to 50 catalyst particles of greater than 100 μm per five grams of the ethylene polymer.

Disclosed herein are processes, systems, and reaction systems for the oligomerization of ethylene to form an oligomer product in a reaction zone using a catalyst system having i) a chromium component comprising a heteroatomic ligand chromium compound complex of the type disclosed herein, and ii) an aluminoxane. Ethylene can be contacted with an organic reaction medium to form an ethylene feedstock mixture prior to contact with the catalyst system. The ethylene feedstock mixture can be contacted with the catalyst system inside or outside of the reaction zone.

The invention provides a process to form a composition comprising at least one ethylene-based polymer and at least one oil, said process comprising the following: polymerizing a mixture comprising ethylene, and optionally one or more comonomers, in a reactor system, comprising at least one reactor and at least one mixer, located downstream from the reactor, to form the ethylene-based polymer; and wherein the oil is added to the ethylene-based polymer upstream of the mixer. The invention also provides a reactor system for a process to form a composition comprising at least one ethylene-based polymer and at least one oil, said reactor system comprising at least one reactor, at least one mixer, and an oil feed into the ethylene-based polymer, and wherein the oil feed is located after the reactor and before the mixer.

Techniques are provided for seal flush systems. A system may include a reactor circulation pump configured to circulate a slurry through a polymerization reactor. The slurry may include an olefin monomer, a catalyst, and a diluent. The system may also include a catalyst-inhibiting additive system configured to supply a catalyst-inhibiting additive to a seal of the reactor circulation pump and a seal flush system configured to generate a seal flush mixture and supply the seal flush mixture to the seal of the reactor circulation pump.

A reactor system including an enclosed pressure relief system and/or a control system. The enclosed pressure relief system including a slurry separation system communicatively coupled with a pressure relief valve coupled to a loop reactor such that activation of the pressure relief valve results in discharge of a slurry from the loop reactor to the slurry separation system, wherein the slurry separation system is capable of separating solid and liquid components from gas components of the slurry and transmitting the gas components to a flare via a flare header.

Supported chromium catalysts containing a solid oxide and 0.1 to 15 wt. % chromium, in which the solid oxide or the supported chromium catalyst has a particle size span from 0.5 to 1.4, less than 3 wt. % has a particle size greater than 100 μm, and less than 10 wt. % has a particle size less than 10 μm, can be contacted with an olefin monomer in a loop slurry reactor to produce an olefin polymer. Representative ethylene-based polymers produced using the chromium catalysts have a HLMI of 4 to 70 g/10 min, a density from 0.93 to 0.96 g/cm.sup.3, from 150 to 680 ppm solid oxide (such as silica), from 1.5 to 6.8 ppm chromium, and a film gel count of less than 15 catalyst particle gels per ft.sup.2 of 25 micron thick film and/or a gel count of less than or equal to 50 catalyst particles of greater than 100 μm per five grams of the ethylene polymer.