Methods for determining ethylene concentration in an ethylene oligomerization reactor using an ultrasonic flow meter are described, and these methods are integrated into ethylene oligomerization processes and related oligomerization reactor systems.

A method for carrying out catalytic gas phase reactions including providing a tube bundle reactor which has a bundle of reaction tubes that are filled with a catalyst charge and are cooled by a heat transfer medium, conveying a reaction gas through the catalyst charge, the reaction gas flowing into each reaction tube divided into two part flows introduced in the axial direction of the reaction tube at different points in the catalyst charge the catalyst charge has at least two catalyst layers of different activity, wherein the activity of the first catalyst layer, in the flow direction of the reaction gas, is lower than the activity of the at least one other catalyst layer and in step a first part flow is introduced into the first catalyst layer and each further part flow is introduced past the first catalyst layer into the at least one further catalyst layer.

A fixed bed reactor system for the oxidative dehydrogenation of ethane, comprising a catalyst bed wherein the catalyst capacity profile increases along the length of catalyst bed from the upstream end to the downstream end. The catalyst bed may include one or more sections, across one or more fixed bed reactors, that are identified by a change in catalyst capacity. Catalyst capacity, or the ability to convert ethane into ethylene, may be altered by changing the dilution ratio, void fraction, and or the 35% conversion temperature. A method for loading a fixed bed reactor with an increasing catalyst capacity is also described.

The present specification relates to a method comprising: (A) mixing a ferrite-based catalyst molded article with diluent material particles; and (B) adding the mixture to a catalyst reactor, and a method for preparing butadiene using the same.

A method for determining polymer concentration can include synthesizing a polymer in a reactor under a set of parameters, wherein the reactor comprises a solution mixture having a refractive index, and wherein the solution mixture comprises a solvent, a polymer, and optionally a monomer, wherein the solution mixture has a polymer concentration; measuring the refractive index of the solution mixture; comparing the refractive index of the solution mixture with a calibration curve; and identifying the polymer concentration in the solution mixture. A system for determining polymer concentration can include a reactor containing a solution mixture comprising a solvent, a polymer, and optionally a monomer; a flash vessel fluidly coupled to the reactor to receive the solution mixture from the reactor; and a first refractometer fluidly coupled to the reactor, placed between the reactor and the flash vessel, and configured to measure a refractive index of the solution mixture.

A manufacturing apparatus of a precursor for positive electrode active material includes a reactor configured to receive a reaction solution and produce a precursor for positive electrode active material through a co-precipitation reaction of the reaction solution, a filtration unit disposed inside the reactor and configured to discharge a filtrate excluding solids in the reaction solution to the outside of the reactor when the reaction solution reaches a predetermined solution level, an extraction unit configured to extract a portion of the reaction solution when the size of a precursor particle in the reaction solution reaches a predetermined size, and a storage tank configured to receive a reaction solution extracted from the reactor through the extraction unit. A method of manufacturing and the precursor are also provided.

Methods for determining the catalytic activity of an activated chemically-treated solid oxide using a color measurement technique are described, and these methods are integrated into transition metal-based catalyst preparation processes and systems, as well as into olefin polymerization processes and related polymerization reactor systems.

A method of monitoring a solid component of a reactor feed stream in a polymer production system, comprising (a) measuring a turbidity of the reactor feed stream, wherein the reactor feed stream comprises a solid component of a polymerization catalyst system, and (b) translating the turbidity of the reactor feed stream into a concentration of the solid component in the reactor feed stream. A method of monitoring a solid component of a reactor feed stream in a polymer production system, comprising (a) measuring a turbidity of a precontactor feed stream, wherein the precontactor feed stream comprises a solid component of a polymerization catalyst system, and (b) translating the turbidity of the precontactor feed stream into a concentration of the solid component in a precontactor effluent stream, wherein the precontactor effluent stream comprises the reactor feed stream.

A method for carrying out catalytic gas phase reactions including providing a tube bundle reactor which has a bundle of reaction tubes that are filled with a catalyst charge and are cooled by a heat transfer medium, conveying a reaction gas through the catalyst charge, the reaction gas flowing into each reaction tube divided into two part flows introduced in the axial direction of the reaction tube at different points in the catalyst charge the catalyst charge has at least two catalyst layers of different activity, wherein the activity of the first catalyst layer, in the flow direction of the reaction gas, is lower than the activity of the at least one other catalyst layer and in step a first part flow is introduced into the first catalyst layer and each further part flow is introduced past the first catalyst layer into the at least one further catalyst layer.

Processes and apparatus for preparing bimodal polymers are provided. In some embodiments, processes include introducing a monomer, a first diluent, a catalyst, hydrogen, at a first hydrogen concentration, and optional comonomer, to a first loop reactor to produce, under polymerization conditions, a first slurry of polymer solids. Processes may also include continuously discharging the first slurry of polymer solids from the loop reactor as a first polymerization effluent to a first flash tank; separating the first polymerization effluent in the first flash tank to provide a first concentrated polymer slurry with significantly lower hydrogen concentration; and transferring the first concentrated polymer slurry from the flash tank to a re-slurry mixer. Processes may further include introducing a re-slurry mixer diluent to the first concentrated polymer slurry to form a second concentrated polymer slurry in the re-slurry mixer that can be pumped to a second slurry loop reactor.