Hydrotreating Catalyst Activation via Acid-Organic Additive Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hydrotreating catalyst activation processes are insufficient in achieving high activity levels, especially in fresh calcined catalysts with significant crystalline fractions, and do not effectively maintain additive presence during the activation process.
Innovation Solution
A process involving the use of an acid and an organic additive with specific boiling and solubility properties is applied to hydrotreating catalysts, incorporating the additive through impregnation and aging steps to reduce the crystalline fraction and enhance catalyst activity, suitable for both fresh and used catalysts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional activation processes are used on fresh calcined catalysts, then the catalyst can be activated, but the significant crystalline fraction results in insufficient activity levels
Solution Approach 1:
The invention changes the chemical environment parameters by introducing specific organic additives (carboxylic acids, phenols, or their salts) during activation. These additives interact with the crystalline metal oxides on the catalyst surface, dissolving or transforming them into more active amorphous forms. The controlled chemical parameters (additive concentration, pH, temperature) enable conversion of the stable but inactive crystalline phase into an active form without compromising catalyst structure.
Solution Approach 2:
Organic additives serve as intermediaries between the crystalline metal oxide phase and the desired active catalyst state. These additives (carboxylic acids, phenols, or their salts) act as chelating agents that bind to metal ions in the crystalline structure, facilitating their transformation into active dispersed phases. The intermediary compounds enable the transition from stable crystalline form to active amorphous form by providing a chemical pathway for transformation.
2Reliability
If drying conditions are applied to remove solvent, then the catalyst can be processed, but the additive may be lost reducing catalyst performance
Solution Approach 1:
The invention optimizes drying parameters (temperature, time, atmosphere) to remove solvent while preserving the thermally sensitive organic additives. By controlling the drying temperature to remain below the decomposition temperature of the additives and using gentle removal conditions, the process achieves solvent elimination without significant additive loss, maintaining catalyst activity.
Solution Approach 2:
The catalyst structure is prepared in advance to accommodate and retain the organic additives. The porous support structure and metal oxide phases are pre-treated to create binding sites that anchor the additives before drying. This preliminary structuring ensures that during subsequent drying and processing steps, the additives remain retained in the catalyst pores rather than being washed or evaporated away.
3Duration of action of stationary object
If used catalysts are regenerated, then they can be reused, but their activity decreases compared to fresh catalysts
Solution Approach 1:
The invention recovers activity in regenerated catalysts by applying the organic additive treatment specifically tailored to restore the active phase. Used catalysts that have lost activity due to crystallization or deactivation are treated with carboxylic acids, phenols, or their salts during activation, which re-dissolve crystalline phases and regenerate the active amorphous metal oxide phases, recovering near-fresh catalyst performance and extending catalyst lifespan.
Solution Approach 2:
The invention converts the harmful effect of crystallization (which causes deactivation) into a beneficial recovery process. The same crystalline phases that cause deactivation during use become the target for recovery treatment. By applying organic additives during regeneration, the crystalline deposits are chemically transformed back into active phases, turning the deactivation mechanism into a recoverable state and extending catalyst life.
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 process significantly improves catalyst activity by maintaining at least 50% of the additive within the catalyst, achieving comparable performance to fresh catalysts and extending the lifespan of used catalysts, while reducing energy consumption and increasing cycle length.
Implementation Method 1
incorporating the additive through impregnation and aging steps
Implementation Method 2
drying under such conditions that at least 50 wt % of the additive (relative to the total original amount of additive) is maintained in the catalyst
Data Source
AI summary
The invention pertains to a process for activating an hydrotreating catalyst comprising a Group VIB metal oxide and a Group VIII metal oxide which process comprises contacting the catalyst with an acid and an organic additive which has a boiling point in the range of 80-500° C. and a solubility in water of at least 5 grams per liter (20° C., atmospheric pressure), optionally followed by drying under such conditions that at least 50% of the additive is maintained in the catalyst. The hydrotreating catalyst may be a fresh hydrotreating catalyst or a used hydrotreating catalyst which has been regenerated.