Methanol Conversion Using Hydrogen Removal to Boost Gasoline Yield
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methanol-to-gasoline (MTG) and methanol-to-olefins (MTO) processes face a trade-off between high yields of low-aromatic gasoline and high-aromatic gasoline with improved octane numbers, as increasing aromatics selectivity reduces gasoline yield due to increased formation of light paraffins like propane and butanes.
Innovation Solution
A process involving the use of a metal-containing zeolite catalyst for converting alcohols or ethers, where hydrogen is partially or completely removed from the synthesis loop to enhance aromatics and C5+ selectivity, reducing the formation of light paraffins and heavy hydrocarbons, thereby improving gasoline yield and octane number.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If pressure or temperature is increased in the gasoline synthesis reactor, then aromatics content and octane number are improved, but gasoline yield is reduced due to increased formation of light paraffins
Solution Approach 1:
The patent extracts and removes light paraffins (propane and butanes) from the reactor effluent before recycling. This prevents their re-entry into the reactor where they would otherwise be converted into aromatics, thereby allowing high aromatics production without the corresponding increase in light paraffin formation that would penalize gasoline yield
Solution Approach 2:
The patent performs preliminary removal of light paraffins from the recycle stream before they enter the reactor. This preliminary action prevents the subsequent formation of excess aromatics from light paraffin conversion, allowing the system to maintain high aromatics selectivity from methanol without the yield penalty
2Manufacturing precision
If pressure or temperature is increased to increase aromatics selectivity, then octane number is improved, but gasoline yield is reduced
Solution Approach 1:
The patent extracts and removes light paraffins (propane and butanes) from the reactor effluent before recycling. This prevents their re-entry into the reactor where they would otherwise be converted into aromatics, thereby allowing high aromatics production without the corresponding increase in light paraffin formation that would penalize gasoline yield
Solution Approach 2:
The patent changes the composition parameter of the recycle stream by removing light paraffins, thereby altering the reaction pathways in the reactor to favor direct methanol conversion to aromatics while suppressing the light paraffin formation and subsequent conversion cycle
3Manufacturing precision
If space velocity is reduced to increase aromatics selectivity, then octane number is improved, but gasoline yield is reduced
Solution Approach 1:
The patent extracts and removes light paraffins (propane and butanes) from the reactor effluent before recycling. This prevents their re-entry into the reactor where they would otherwise be converted into aromatics, thereby allowing high aromatics production without the corresponding increase in light paraffin formation that would penalize gasoline yield
Solution Approach 2:
The patent implements a feedback mechanism where light paraffins are continuously removed from the recycle stream, preventing their accumulation and subsequent conversion to aromatics. This feedback control allows the system to maintain high aromatics selectivity without the yield penalty associated with traditional methods
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 approach increases the aromatics content in the hydrocarbon product, enhancing gasoline yield and octane number while reducing the formation of durene and heavy hydrocarbons, providing a high-aromatic gasoline blendstock suitable for downstream processing.
Implementation Method 1
converting a feed stream comprising alcohols, ethers or mixtures hereof over a metal-containing zeolite based catalyst, active in dehydrogenation of hydrocarbons
Implementation Method 2
converting a feed stream comprising alcohols, ethers or mixtures hereof over a metal-containing zeolite based catalyst
Implementation Method 3
separating said effluent to obtain an aqueous process condensate stream, a liquid hydrocarbon stream and a gaseous stream
Data Source
AI summary
The present application relates to a process for production of hydrocarbons comprising the steps ofconverting a feed stream comprising alcohols, ethers or mixtures hereof over a metal-containing zeolite based catalyst, active in dehydrogenation of hydrocarbons, in a conversion step thereby obtaining a conversion effluent,separating said effluent to obtain an aqueous process condensate stream, a liquid hydrocarbon stream and a gaseous stream,removing part of the hydrogen formed in the conversion step, andrecycling at least part of the gaseous and/or liquid hydrocarbon stream to the conversion step.