Integrated Ethane Process for Acetic Acid and Vinyl Acetate Co-Production

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing integrated processes for producing vinyl acetate do not effectively co-produce sales grade acetic acid in addition to vinyl acetate using ethane as a feedstock, limiting their commercial viability due to low reaction pressures and productivity.

Innovation Solution

An integrated process that reacts ethane with oxygen in the presence of a first catalyst to produce ethylene and some acetic acid, splits the ethylene into two portions, and reacts one portion with oxygen in the presence of a second catalyst to produce additional acetic acid, while reacting the remaining ethylene and acetic acid with a third catalyst to produce vinyl acetate.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If existing integrated processes use ethane as feedstock to produce vinyl acetate, then vinyl acetate production is achieved, but acetic acid production is insufficient and commercial viability is limited

Engineering Contradiction:
Improveacetic acid productionVSAvoidco-production capability
Core Design Contradiction:
Quantity of substanceVSAdaptability or versatility

Solution Approach 1:

The process segments ethane conversion into two distinct pathways: (1) oxidative dehydrogenation to ethylene, and (2) oxidation to acetic acid. By splitting the ethylene stream, the process directs one portion to vinyl acetate production while another portion undergoes oxidation to generate additional acetic acid, thereby resolving the contradiction between vinyl acetate production and acetic acid production capability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The integrated process system performs multiple functions simultaneously: it produces vinyl acetate as the primary product while also generating sales-grade acetic acid as a co-product. The multi-functional catalyst system enables both oxidative dehydrogenation and oxidation reactions, allowing the process to adapt to produce both chemicals from a single ethane feedstock

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Productivity

If low reaction pressures are used in ethane oxidation, then selectivity is maintained, but productivity is restricted

Engineering Contradiction:
Improvereaction productivityVSAvoidconversion selectivity
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The process employs different catalysts with specialized functions in different reaction zones: the first catalyst is optimized for oxidative dehydrogenation to ethylene, while the second catalyst is specifically designed for oxidation to acetic acid. This local optimization of catalyst properties allows each reaction to proceed with high selectivity while maintaining overall high productivity through the integrated multi-pathway system

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

This process enables the flexible co-production of sales grade acetic acid and vinyl acetate, enhancing productivity and reducing capital and operating costs by utilizing ethane as a feedstock, thereby improving the commercial viability of the process.

Implementation Method 1

reacting ethane with oxygen in the presence of a first catalyst to produce ethylene and some acetic acid

Methodology Applied
Scientific EffectCatalysis: Catalysis

Implementation Method 2

reacting ethane with oxygen in the presence of a first catalyst to produce ethylene and some acetic acid

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 3

reacting the first portion of the ethylene with oxygen in the presence of a second catalyst to produce acetic acid

Methodology Applied
Scientific EffectCatalysis: Catalysis

Implementation Method 4

reacting the first portion of the ethylene with oxygen in the presence of a second catalyst to produce acetic acid

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 5

reacting the second portion of the ethylene and a portion of the acetic acid in the presence of a third catalyst to produce vinyl acetate

Methodology Applied
Scientific EffectCatalysis: Catalysis

Data Source

PatentEP1989161B1Integrated process for the production of acetic acid and vinyl acetate
Publication Date: 2013.05.15 CELANESE INTERNATIONAL CORP
  • EP1989161B1 patent drawingFigure 1

AI summary

The present invention provides an integrated process for the production of acetic acid and vinyl acetate from an essentially ethane feed, comprising the steps reacting ethane with oxygen in the presence of a catalyst to produce ethylene and some acetic acid, reacting a first portion of the ethylene with oxygen in the presence of a catalyst to produce acetic acid, and reacting a second portion of the ethylene and a portion of the purified acetic acid in the presence of a catalyst to produce vinyl acetate.