Exxonmobil Chemical Patents Inc.

Exxon Chemical Patents, Inc.

Robert L Long

Carl J Thomas

Michael F McDonald, Jr

Richard C Yeh

David Geoffrey Marrow

Oscar Kearney Broussard, Iii

Robert Alan Schaefer

Bruce Charles Devoy

Stephen K Morgan

Paul A Bartel

Robert Earl Young

There is provided a closed loop purity and recovery control system and process for operating a xylene purification system such as a Parex unit.

Feedback and feedforward closed loop purity and recovery control

The invention is a method and apparatus for on-line measurement of polymer properties such as moisture content, ethylene content, Epoxidized Soy Bean Oil (ESBO) content, calcium stearate content and ethylidene norbornene (ENB) content.

Method and apparatus for on-line measurement of polymer properties

Methods are provided for determining and controlling polymer properties on-line in a polymerization reactor system, such as a fluidized bed reactor. The methods include obtaining a regression model for determining a polymer property, the regression model including principal component loadings and principal component scores, acquiring a Raman spectrum of a polyolefin sample comprising polyolefin, calculating a new principal component score from at least a portion of the Raman spectrum and the principal component loadings, and calculating the polymer property by applying the new principal component score to the regression model. The property can be controlled by adjusting at least one polymerization parameter based on the calculated polymer property.

On-line measurement and control of polymer properties by raman spectroscopy

An apparatus for dewatering a slurry of elastomeric polymer and water, using an extruder or extruders provided with a device for measuring an actual water content of the elastomer at a position within the extruder or extruders, and a control system for controlling the moisture content of elastomeric polymer exiting the extruder or extruders through an exit die based, at least in part, on the measured water content.

Apparatus dewatering an elastomeric polymer

Method of olefin polymerization in a reactor, such as a slurry loop olefin polymerization reactor, is provided. The method includes conducting in-situ, real time spectroscopic analysis of one or more reactor constituents. The reactor constituents analyzed may be present in the reactor in either the liquid phase or the solid phase, or both. In response to the measured in-situ values, one or more reactor constituents may be metered into the reactor.

Raman analysis system for olefin polymerization control

A process plant for the manufacture of halobutyl rubber is provided with online monitoring and control of the process parameters to control the properties of the product. It incorporates an in-situ measurement system that does not require the removal of any sample material from the process. It uses a Fourier Transform Near Infrared (FTNIR) spectrometer, fiber-optic cables, a viscometer for measuring solution viscosity and a Resistance Temperature Device (RTD) for temperature measurement. An online real-time analyzer system using a Constrained Principal Spectral Analysis program predicts the property of the polymer product and provides the process control system with analysis of the data using derived relationships between the physical properties of the polymer and these spectral measurements and the measured values of fluid viscosity and temperature. Differences between the predicted and desired property of the product are used to control process parameters. The method can be used for a variety of chemical process plants.

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Houston, TX, United States of America

Robert L Long