Bicyclic Fused-Ring Alkane Synthesis via Cyclitol C-C Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current processes for preparing bicyclic fused-ring alkanes are complex, have low yield, and require severe reaction conditions and limited raw material sources, leading to inefficient production of high-density jet fuels.
Innovation Solution
A two-step process using a bifunctional solid catalyst for C—C coupling and hydrogenation of cyclitols in a nitrogen atmosphere, followed by hydrogenation in a mild pressure environment, to produce bicyclic fused-ring alkanes with a controlled composition ratio of at least 80%.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a two-step process with separation and purification is used to prepare bicyclic fused-ring alkanes, then the product purity is improved, but the process complexity and production cost increase
Solution Approach 1:
The patent combines the C-C coupling reaction and hydrogenation reaction into a single one-pot process without intermediate separation and purification steps. The reaction system directly transforms cyclitol raw materials into bicyclic fused-ring alkanes through sequential reactions in the same reactor, eliminating complex separation equipment and operations while maintaining high product purity through selective catalysis.
Solution Approach 2:
The patent implements a continuous one-pot reaction process where the C-C coupling and hydrogenation occur sequentially without interruption. The reaction mixture remains in the reactor throughout both transformation stages, with the catalyst system facilitating both reactions continuously, thereby eliminating the need for intermediate isolation and purification steps.
2Productivity
If conventional catalysts are used for hydrogenation, then the hydrogenation reaction can proceed, but the reaction requires high pressure and high temperature conditions
Solution Approach 1:
The patent employs a bifunctional catalyst system that enables the hydrogenation reaction to proceed under milder conditions compared to conventional catalysts. The unique catalyst composition and structure allow the reaction to occur at lower temperatures and pressures while maintaining high conversion efficiency, thereby reducing energy consumption and equipment requirements.
3Productivity
If conventional hydrogenation methods are used, then the hydrogenation reaction can be completed, but high hydrogen pressure is required
Solution Approach 1:
The patent utilizes a specially designed bifunctional catalyst system that significantly reduces the hydrogen pressure requirement for the hydrogenation reaction. The catalyst's unique properties enable efficient hydrogen activation and transfer at lower pressures, thereby reducing equipment complexity and operational costs while maintaining high reaction efficiency.
4Quantity of substance
If a C-C coupling reaction is used to produce bicyclic fused-ring products, then the target product can be obtained, but the molar ratio of target product to linear bicyclic alkane cannot be effectively controlled
Solution Approach 1:
The patent employs a bifunctional catalyst system with specific acidic and metallic sites that work synergistically to control the reaction pathway. The acidic sites facilitate C-C coupling to form the fused-ring structure, while the metallic sites promote hydrogenation, thereby selectively guiding the reaction toward the bicyclic fused-ring alkane product and suppressing linear bicyclic alkane formation through localized catalytic activity.
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 method simplifies the production process, increases yield, reduces severe reaction conditions, and utilizes widely available cyclitol raw materials, enabling efficient and cost-effective industrial production of high-density, high-caloric value jet fuels with improved low-temperature flow ability.
Implementation Method 1
in the presence of a bifunctional solid catalyst, one or more cyclitols undergo a C—C coupling reaction
Implementation Method 2
the bicyclic alkane precursor mixture is hydrogenated or hydrodeoxygenated to produce said bicyclic fused-ring alkane
Data Source
AI summary
A process for preparation of a bicyclic fused-ring alkane. In the presence of a bifunctional solid catalyst, one or more cyclitols undergo a C—C coupling reaction with itself or each other at a temperature and in a nitrogen gas atmosphere, to produce a bicyclic alkane precursor mixture; then, the nitrogen gas is replaced by hydrogen gas, and the bicyclic alkane precursor mixture is hydrogenated or hydrodeoxygenated at a temperature and under a pressure, to produce the bicyclic fused-ring alkane. The proportion of the bicyclic fused-ring alkane in the product as prepared according to the process is not lower than 80 wt %.