Cerium Overbased Additive Two-Step Carbonation

Solution Overview

Problem

Existing processes for preparing overbased additives with cerium and alkaline earth metals struggle to achieve high basicity and stability in lubricating oils, particularly due to challenges in increasing cerium content and preventing colloidal coagulation and gel formation.

Innovation Solution

A two-step carbonation process is employed in the synthesis of oil dispersions of overbased salts containing cerium and alkaline earth metals, using an oil dispersion of cerium salts treated with an alkaline earth metal hydroxide or oxide, followed by carbonation with carbon dioxide in multiple stages, to achieve high cerium content and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the cerium content in organic acid compounds is increased to improve neutralization degree, then the efficiency as antiwear and anti-friction additives is improved, but the preparation of stable colloidal dispersions becomes more difficult

Engineering Contradiction:

Improvecerium contentVSAvoidcolloidal dispersion stability

Core Design Contradiction:

Quantity of substanceVSStability of the object's composition

Solution Approach 1:

The carbonation process is divided into multiple sequential steps (first carbonation step, second carbonation step, and optionally third carbonation step) rather than a single step. This segmentation allows progressive formation of overbased salts with controlled cerium content, preventing colloidal coagulation and gel formation while achieving high neutralization degree and stable dispersions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The process performs preliminary carbonation steps before completing the full carbonation. The first and second carbonation steps prepare intermediate overbased salt products with controlled properties, which then serve as basis for final product. This preliminary action allows gradual incorporation of cerium while maintaining colloidal stability throughout the process

Inventive Principle:

Principle #10Preliminary action

2Device complexity

If a single carbonation step is used to simplify the process, then the manufacturing complexity is reduced, but the resulting dispersion shows coagulation and gel formation

Engineering Contradiction:

Improveprocess complexityVSAvoidcolloidal dispersion stability

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

The carbonation process is divided into multiple sequential steps (first carbonation step, second carbonation step, and optionally third carbonation step) rather than a single step. This segmentation allows progressive formation of overbased salts with controlled cerium content, preventing colloidal coagulation and gel formation while achieving high neutralization degree and stable dispersions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The process performs preliminary carbonation steps before completing the full carbonation. The first and second carbonation steps prepare intermediate overbased salt products with controlled properties, which then serve as basis for final product. This preliminary action allows gradual incorporation of cerium while maintaining colloidal stability throughout the process

Inventive Principle:

Principle #10Preliminary action

3Reliability

If high basicity is achieved through complete neutralization, then the detergent and anti-friction performance is improved, but colloidal coagulation and gel formation occur

Engineering Contradiction:

ImprovebasicityVSAvoidcolloidal dispersion stability

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The carbonation process is divided into multiple sequential steps (first carbonation step, second carbonation step, and optionally third carbonation step) rather than a single step. This segmentation allows progressive formation of overbased salts with controlled cerium content, preventing colloidal coagulation and gel formation while achieving high neutralization degree and stable dispersions

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The process performs preliminary carbonation steps before completing the full carbonation. The first and second carbonation steps prepare intermediate overbased salt products with controlled properties, which then serve as basis for final product. This preliminary action allows gradual incorporation of cerium while maintaining colloidal stability throughout the process

Inventive Principle:

Principle #10Preliminary action

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 approach results in stable, high-basicity colloidal dispersions with improved cerium content, preventing coagulation and gel formation, enhancing the additives' performance as detergent, anti-friction, and anti-wear agents in lubricant oils and diesel engine emissions treatment.

Implementation Method 1

subsequent carbonation with carbon dioxide, carried out in two or more subsequent steps

Methodology Applied

Scientific EffectCarbonation: Chemical Bonding

Implementation Method 2

obtain a colloidal dispersion of these salts which can be easily filtered, is stable in oil and consequently has no problems of coagulation of the colloid with the formation of gel

Methodology Applied

Scientific EffectColloidal stability: Colloid

Data Source

PatentEP2356203B1Process for the preparation of additives for lubricants containing cerium

Publication Date: 2013.05.29 ENI SPA

AI summary

Improved process for the synthesis of oil dispersions of overbased salts containing cerium and an alkaline earth metal, comprising the treatment of an oil dispersion of cerium salts of organic acids with a hydroxide or an oxide of an alkaline earth metal and subsequently subjecting said overbased dispersion to carbonation with carbon dioxide, characterized in that said carbonation is carried out in two or more subsequent steps.