Boron Hydroprocessing Catalysts With Stable Pore Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for introducing boron into hydroprocessing catalysts face inefficiencies, such as boron elution from filter cakes, difficulty in metering, and the formation of detrimental macropores, leading to reduced catalytic activity and stability.
Innovation Solution
A method involving combining a porous inorganic oxide catalyst carrier with a boron-containing source and an organic compound, followed by calcination and impregnation with Group VIB and VIIIB metal components, allowing precise control of boron concentration and maintaining desired pore size distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If boric acid is added directly to the alumina batch tank during synthesis, then boron can be introduced into the catalyst, but large amounts of boron elute from the filter cake and the process is inefficient and difficult to control
Solution Approach 1:
The patent applies preliminary action by adding boron to the alumina precipitate after synthesis rather than during synthesis. The boron is incorporated into the filter cake structure before the final drying and calcination steps, ensuring stable integration without elution. This timing allows the alumina structure to be fully formed and capable of retaining boron.
Solution Approach 2:
The patent uses an intermediary approach by introducing boron through the filtration and drying process rather than direct addition to the synthesis tank. The boron is added to the slurry or precipitate and becomes part of the filter cake matrix, using the filtration process itself as the delivery mechanism rather than direct tank addition.
2Quantity of substance
If boron is added during drying or in subsequent mixing steps, then boron can be incorporated into the catalyst, but macropore formation occurs which is detrimental to catalytic activity
Solution Approach 1:
The patent applies preliminary action by adding boron before the drying step but in a controlled manner that prevents macropore formation. The boron is incorporated into the wet precipitate or filter cake where it becomes uniformly distributed in the fine structure before drying locks the pore structure in place. This timing allows boron integration without disrupting the developing pore network.
3Quantity of substance
If pore volume impregnation is used to add boron, then boron can be introduced into the catalyst pores, but the solubility of boric acid limits the concentration of B2O3 to less than 1 wt %
Solution Approach 1:
The patent applies parameter changes by altering the physical state and chemical form of boron. Instead of using aqueous boric acid solutions limited by solubility, the patent uses boron compounds that can be applied as slurries, suspensions, or dry powders. This changes the delivery parameter from liquid solution concentration to solid loading, bypassing solubility limits and enabling higher boron concentrations.
Solution Approach 2:
The patent uses an intermediary approach by employing organic compounds or chelating agents as mediators between the boron source and the catalyst support. These intermediaries facilitate the incorporation of high concentrations of boron into the catalyst structure without requiring aqueous solutions, thus overcoming the solubility constraint of boric acid.
4Ease of manufacture
If conventional methods are used to add boron, then the process is simple, but catalytic activity and stability are reduced due to macropore formation and boron elution
Solution Approach 1:
The patent maintains ease of manufacture by using a straightforward addition process similar to conventional methods, but improves reliability by changing when the addition occurs. Boron is added to the precipitate or filter cake in the existing production flow, requiring no complex equipment changes, while the timing ensures stable incorporation without elution or macropore formation.
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 enhances catalytic activity for hydrodesulfurization and hydrodenitrogenation, mitigates macropore formation, and enables flexible adjustment of boron content without altering pore structure, resulting in high-performance catalysts with improved stability.
Implementation Method 1
combining a porous inorganic oxide catalyst carrier or carrier extrudate with an aqueous solution, dispersion or suspension comprising: (i) a boron-containing source; and (ii) an organic compound or organic chelating agent
Implementation Method 2
calcining, or drying and calcining the composition or extrudate formed in (a) to reduce its volatiles content to a level of greater than 0 wt % to less than about 5 wt %, as measured by Loss on Ignition (LOI)
Implementation Method 3
impregnating the calcined composition formed in (b) with a solution, dispersion or suspension comprising at least one Group VIB metal-containing component or source and at least one Group VIIIB metal-containing component or source
Data Source
AI summary
A method of producing a support, and supported catalyst, the method comprising: (a) combining a porous inorganic oxide catalyst carrier or carrier extrudate with an aqueous solution, dispersion or suspension comprising: (i) a boron-containing source; and (ii) an organic compound or organic chelating agent selected from organic compounds comprising at least two oxygen atoms and 2-10 carbon atoms; (b) calcining the composition (a) to reduce its Loss on Ignition (LOI) volatiles content to greater than 0 wt % to less than about 5 wt %; (c) impregnating the calcined composition an aqueous composition comprising at least one each of a Group VIB and Group VIIIB metal-containing source; and (d) calcining, to reduce its LOI volatiles content greater than 0 wt % to less than about 30 wt %; wherein the boron content of a supported catalyst is in the range of about 1 wt % to about 13 wt B2O3 based on the total weight of the catalyst.