Multimetallic Catalysts for n-Butane Dehydrogenation

Solution Overview

Problem

Platinum group catalysts used in n-butane dehydrogenation reactions suffer from instability and deactivation due to harsh conditions and active-site sintering, especially when supported on silica, which results in poor selectivity and short catalyst lifetime.

Innovation Solution

A catalyst system comprising a substrate surface of high-surface-area oxides like SiO2, Al2O3, or ZrO2 with a transition metal or main group element oxide promoter and a platinum group metal catalyst, where the promoter and catalytic metal are deposited using techniques like atomic layer deposition to enhance stability and selectivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If platinum group catalysts are used for n-butane dehydrogenation, then catalytic activity is achieved, but catalyst stability and lifetime deteriorate due to harsh conditions and active-site sintering

Engineering Contradiction:

Improvecatalyst stabilityVSAvoidcatalyst lifetime

Core Design Contradiction:

ReliabilityVSDuration of action of moving object

Solution Approach 1:

The patent employs composite catalyst structures combining platinum group metals with metal oxides (such as Pt-Zn-Al, Pt-B, Pt-Zr) supported on high-surface-area substrates. This composite approach creates synergistic effects where the metal oxide components prevent sintering of platinum sites while maintaining catalytic activity, thereby extending catalyst lifetime under harsh dehydrogenation conditions.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent utilizes high-surface-area substrates (mesoporous silica, alumina, titania, zirconia) to provide localized high-surface-area sites for platinum dispersion. This local quality enhancement ensures maximum platinum utilization and prevents bulk sintering by confining metal particles on high-surface-area support structures, improving both stability and lifetime.

Inventive Principle:

Principle #3Local quality

2Area of stationary object

If silica supports are used for platinum catalysts, then high-surface area is achieved, but catalyst selectivity and stability worsen due to facile sintering

Engineering Contradiction:

Improvesurface areaVSAvoidcatalyst stability

Core Design Contradiction:

Area of stationary objectVSReliability

Solution Approach 1:

The patent employs high-surface-area substrates (mesoporous silica, alumina, titania, zirconia) to provide localized high-surface-area sites for platinum dispersion. This local quality enhancement ensures maximum platinum utilization and prevents bulk sintering by confining metal particles on high-surface-area support structures, improving both stability and lifetime.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent combines silica supports with metal oxide promoters (ZnO, Al2O3, TiO2, ZrO2) to create composite support structures. These composite materials maintain the high surface area of silica while the metal oxide components provide structural stability and prevent platinum sintering, resolving the contradiction between surface area and stability.

Inventive Principle:

Principle #40Composite materials

3Reliability

If alumina supports are used, then catalyst support is provided, but harmful cracking reactions occur producing lower value hydrocarbon fragments

Engineering Contradiction:

Improvecatalyst support stabilityVSAvoidcracking reactions

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent employs high-surface-area substrates (mesoporous silica, alumina, titania, zirconia) to provide localized high-surface-area sites for platinum dispersion. This local quality enhancement ensures maximum platinum utilization and prevents bulk sintering by confining metal particles on high-surface-area support structures, improving both stability and lifetime.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent modifies the chemical properties of alumina supports by doping with metal oxides (ZnO, Al2O3, TiO2, ZrO2) to change the surface acidity parameters. This parameter change reduces the strong Lewis acid sites responsible for cracking reactions while maintaining the structural stability and support function of alumina, thereby eliminating harmful effects.

Inventive Principle:

Principle #35Parameter changes

4Productivity

If high surface area substrates are used, then catalyst activity is improved, but selectivity and stability worsen due to sintering

Engineering Contradiction:

Improvecatalyst activityVSAvoidcatalyst stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent employs high-surface-area substrates (mesoporous silica, alumina, titania, zirconia) to provide localized high-surface-area sites for platinum dispersion. This local quality enhancement ensures maximum platinum utilization and prevents bulk sintering by confining metal particles on high-surface-area support structures, improving both stability and lifetime.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent combines high-surface-area substrates with metal oxide promoters to create composite catalyst structures. These composite materials maintain the high surface area needed for activity while the metal oxide components provide structural stability and prevent sintering, simultaneously achieving productivity and reliability.

Inventive Principle:

Principle #40Composite materials

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

The catalyst system achieves high selectivity and stability for n-butane dehydrogenation, maintaining activity and reducing coke deposition, with boron-doped catalysts showing enhanced thermal stability and selectivity to 1,3-butadiene and butenes, even at elevated temperatures.

Implementation Method 1

a promoter consisting essentially of MOx where M is a transition metal or main group elemental oxide, the promoter deposited on the substrate

Methodology Applied

Scientific EffectAdsorption: Adsorption

Implementation Method 2

Catalysts provide a vital mechanism for facilitating modern industrial-scale chemical production. Catalytic n-butane dehydrogenation is very important for the production of butenes and 1,3-butadiene

Methodology Applied

Scientific EffectCatalysis: Catalysis