Multi-Stage Base Oil Processing for Low Aromatics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern refining processes for producing lubricating oils often result in base oils with undesirable levels of aromatics, residual organic sulfur, and nitrogen, which affect the quality and performance of the lubricating oils.
Innovation Solution
A process involving a sulfur reduction step using a base metal catalyst followed by a noble metal hydrofinishing catalyst to reduce residual refractory sulfur compounds, resulting in a hydrofinished stream with less than 0.4% aromatics by weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional hydrogen processes (hydrotreating, hydrocracking, hydrodewaxing, hydrofinishing) are used to produce lubricating oils, then viscosity index and low temperature properties are improved, but undesirable levels of aromatics, residual organic sulfur, and nitrogen remain
Solution Approach 1:
The patent divides the base oil production process into multiple sequential stages: hydrodewaxing stage, sulfur reduction stage, and hydrofinishing stage. Each stage uses a specific catalyst configuration (noble metal catalyst, base metal catalyst, then noble metal catalyst again) to address specific contaminants at different points in the process, thereby achieving comprehensive removal of aromatics, sulfur, and nitrogen while maintaining base oil quality
Solution Approach 2:
The patent introduces a base metal catalyst as an intermediary component between the hydrodewaxing and hydrofinishing stages. This intermediate sulfur reduction stage specifically targets and removes refractory sulfur compounds that would otherwise interfere with the subsequent hydrofinishing process, enabling the noble metal hydrofinishing catalyst to more effectively remove aromatics and nitrogen
2Manufacturing precision
If additional or alternative processes are implemented to reduce aromatics, sulfur, and nitrogen, then base oil quality is improved, but process complexity increases
Solution Approach 1:
The patent combines multiple contaminant removal functions into a unified multi-stage process architecture. By integrating hydrodewaxing, sulfur reduction, and hydrofinishing operations in sequence, each with specialized catalysts, the process achieves comprehensive removal of multiple contaminant types (aromatics, sulfur, nitrogen) through a coordinated system rather than separate independent processes
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 process efficiently produces low aromatic base oils with improved properties, achieving a significant reduction in aromatics content and enhancing the quality of lubricating oils.
Implementation Method 1
contacting a first isomerized stream comprising an amount of residual refractory sulfur compounds with a base metal catalyst under conditions to provide a second isomerized stream comprising a lesser amount of residual refractory sulfur compounds than the first isomerized stream
Implementation Method 2
The noble metal hydrofinishing catalyst under hydrofinishing conditions to provide a hydrofinished stream
Implementation Method 3
contacting the second isomerized stream with a noble metal hydrofinishing catalyst under hydrofinishing conditions to provide a hydrofinished stream
Data Source
AI summary
Described are processes to produce base oils with one more improved properties, e.g., lower aromatics, economically and/or efficiently. In some embodiments the processes comprise a step that reduces the amount of residual refractory sulfur compounds prior to or simultaneous with a hydrofinishing step which advantageously provides base oils with lower aromatics than comparable processes.