UV-Vis Curve Fitting for Multimetal Concentration Monitoring

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods fail to accurately and efficiently determine the concentrations of multiple transition metal compounds in solutions, especially when their UV-Vis spectra overlap or when one compound is in large excess, hindering real-time monitoring and control in polymerization processes.

Innovation Solution

A process using UV-Vis spectroscopy involves providing reference absorbance profiles for each transition metal compound, submitting a sample to a chamber, irradiating it with UV-visible light, and calculating a curve to fit the sample absorbance profile, allowing for precise determination of concentrations through least-squares regression, even in overlapping spectra or excess conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If UV-Vis spectroscopy is used to determine concentrations of multiple transition metal compounds, then real-time monitoring capability is improved, but measurement precision deteriorates when spectra overlap or one compound is in large excess

Engineering Contradiction:
Improvereal-time monitoring capabilityVSAvoidconcentration determination accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent segments the overlapping absorbance spectrum into multiple wavelength regions, analyzing each region separately to determine individual compound concentrations. By dividing the spectral analysis into distinct segments rather than treating it as a whole, the method can resolve concentrations even when spectra overlap significantly or when one compound is in large excess.

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If conventional spectroscopic methods are used, then determination of individual compound concentrations is attempted, but measurement precision worsens when UV-Vis spectra overlap

Engineering Contradiction:
Improveindividual concentration determinationVSAvoidspectrum overlap complexity
Core Design Contradiction:
Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent transforms the spectral analysis from a single-dimension problem (overall absorbance) to a multi-dimensional problem by analyzing multiple wavelength regions independently. This dimensional expansion allows the method to resolve individual compound concentrations even when their spectra overlap in the traditional single-wavelength approach.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Measurement precision

If standard analysis methods are applied, then concentration measurement is performed, but measurement precision deteriorates when one compound is in large excess relative to another

Engineering Contradiction:
Improveconcentration ratio determinationVSAvoidconcentration disparity between compounds
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent applies local quality analysis by selecting specific wavelength regions where each compound exhibits characteristic absorbance properties. Even when one compound is in large excess, the method identifies and analyzes local spectral features unique to each compound, enabling accurate determination of both concentrations regardless of their relative abundance differences.

Inventive Principle:
Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables precise, real-time monitoring and control of transition metal compound concentrations in polymerization processes, improving the quality and consistency of polymer products by accurately determining individual concentrations even in complex scenarios.

Implementation Method 1

irradiating the sample in the chamber with a light beam at a wavelength in the UV-visible spectrum, and generating a sample absorbance profile of the sample

Methodology Applied
Scientific EffectAbsorption Spectroscopy: Absorption Spectroscopy

Data Source

PatentEP3774019B1Methods for determining transition metal compound concentrations in multicomponent liquid systems
Publication Date: 2022.08.03 CHEVRON PHILLIPS CHEMICAL COMPANY LP
  • EP3774019B1 patent drawingFigure 1
  • EP3774019B1 patent drawingFigure 2
  • EP3774019B1 patent drawingFigure 3

AI summary

Methods for simultaneously determining the concentrations of transition metal compounds in solutions containing two or more transition metal compounds are described. Polymerization reactor systems providing real-time monitoring and control of the concentrations of the transition metal components of a multicomponent catalyst system are disclosed, as well as methods for operating such polymerization reactor systems, and for improving methods of preparing the multicomponent catalyst system.