Hydrocarbon-Soluble Molybdenum Catalyst Precursors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalysts used in hydroprocessing heavy oils are prone to fouling and rapid deactivation, leading to increased costs due to the high cost of commercial molybdenum catalysts and inefficient processing of heavy oil feedstocks with high sulfur, nitrogen, and metal content, which are difficult to process and cause fouling of conventional catalysts.
Innovation Solution
Development of hydrocarbon-soluble molybdenum catalyst precursors with a plurality of cationic molybdenum atoms in a 3+ oxidation state, formed in situ, using a reducing agent to enhance solubility and stability, reducing the oxidation state to less than 4+, thereby increasing the weight percent of molybdenum and preventing undesired complex formation, which improves the efficiency of hydrocracking processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional catalysts are used for hydroprocessing heavy oil, then the process can proceed, but the catalysts become fouled and rapidly deactivated due to high sulfur, nitrogen, and metal content in heavy oil
Solution Approach 1:
The patent changes the oxidation state parameter of molybdenum from +4 to +3, creating a reduced molybdenum species that is more resistant to fouling and deactivation by sulfur, nitrogen, and metals in heavy oil. This parameter change transforms the catalyst's chemical properties to withstand the harsh heavy oil processing environment.
Solution Approach 2:
The patent creates a composite catalyst system combining molybdenum in a reduced oxidation state with hydrocarbon solvents, forming a soluble complex that maintains catalytic activity while resisting deactivation. The composite structure allows the catalyst to function effectively in heavy oil without rapid deactivation.
2Productivity
If the concentration of metal in the catalyst precursor is increased to improve efficiency, then the cost decreases, but the solubility in heavy oil may be compromised
Solution Approach 1:
The patent changes the oxidation state parameter of molybdenum to +3, which fundamentally alters the solubility characteristics of the catalyst precursor. This parameter change enables the formation of hydrocarbon-soluble complexes that can maintain high metal concentration while remaining fully dissolved in heavy oil, achieving both high productivity and stability.
3Productivity
If molybdenum catalysts are used to process heavy oil, then conversion rates can be achieved, but the catalyst costs are high and maintenance costs increase due to rapid deactivation
Solution Approach 1:
The patent changes the oxidation state of molybdenum to +3, creating a catalyst that maintains high conversion rates while significantly extending catalyst life. The reduced oxidation state creates a more stable catalytic species that resists deactivation, thereby extending the operational life and reducing both catalyst and maintenance costs.
4Reliability
If existing molybdenum salts with oxidation state 4+ are used, then the catalyst can be formed, but undesired complexes may form and solubility is reduced
Solution Approach 1:
The patent changes the oxidation state parameter from +4 to +3, which fundamentally alters the chemical behavior of molybdenum. This parameter change prevents the formation of undesired complexes while maintaining catalyst formation, as the reduced molybdenum species has different coordination chemistry and reactivity patterns that avoid problematic side reactions.
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 molybdenum catalyst precursors with a 3+ oxidation state improve the processing of heavy oils by reducing fouling, increasing conversion rates, and lowering catalyst costs through enhanced solubility and dispersion, effectively handling high-boiling fractions and asphaltenes, thus extending catalyst life and reducing maintenance costs.
Implementation Method 1
formed in situ, using a reducing agent to enhance solubility and stability, reducing the oxidation state to less than 4+
Implementation Method 2
using a reducing agent to enhance solubility and stability, reducing the oxidation state to less than 4+
Data Source
AI summary
Hydrocarbon-soluble molybdenum catalyst precursors include a plurality of molybdenum cations that are each bonded with a plurality of organic anions to form an oil soluble molybdenum salt. A portion of the molybdenum atoms are in the 3+ oxidation state such that the plurality of molybdenum atoms has an average oxidation state of less than 4+, e.g., less than about 3.8+, especially less than about 3.5+. The catalyst precursors can form a hydroprocessing molybdenum sulfide catalyst in heavy oil feedstocks. The oil soluble molybdenum salts are manufactured in the presence of a reducing agent, such as hydrogen gas, to obtain the molybdenum in the desired oxidation state. Preferably the reaction is performed with hydrogen or an organic reducing agent and at a temperature such that the molybdenum atoms are reduced to eliminate substantially all molybdenum oxide species.