Centrifugal Nanoparticle Separation via Liquid-Liquid Interface

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for separating metal or metal oxide nanoparticles and nanowires face challenges such as agglomeration, low concentration, and inefficient industrial-scale processing, particularly in centrifugation techniques where nanoparticles adhere to centrifuge walls and are difficult to recover without causing downtime.

Innovation Solution

A process using a centrifugal separator that continuously feeds a suspension of nanoparticles in a polar or non-polar solvent with a stabilizer and an inert immiscible solvent, centrifuging at a controlled speed to collect nanoparticles at the liquid-liquid interface, preventing wall deposition and enhancing recovery through anti-solvent addition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional centrifugation is used to separate nanoparticles, then separation is achieved, but nanoparticles adhere to centrifuge walls causing loss of time and reduced productivity

Engineering Contradiction:
Improveseparation efficiencyVSAvoiddowntime for recovery
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent introduces a liquid-liquid interface as an intermediary medium between the nanoparticle suspension and the centrifuge wall. By using two immiscible liquids (aqueous phase and organic phase), nanoparticles are directed to accumulate at the interface rather than adhering to the centrifuge wall, enabling continuous operation without downtime for recovery.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent transitions from conventional single-phase centrifugation to a two-phase liquid-liquid system, adding a dimensional aspect to the separation process. The interface between two liquid phases creates a new separation dimension where nanoparticles can be selectively accumulated based on their affinity for the interface, preventing wall adhesion.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If high concentration of nanoparticles is achieved, then productivity improves, but agglomeration occurs reducing manufacturing precision

Engineering Contradiction:
ImproveconcentrationVSAvoidparticle size distribution
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The liquid-liquid interface acts as a mediator that allows high concentration of nanoparticles without agglomeration. The interface provides a unique environment where nanoparticles can be densely packed while maintaining individual particle integrity, preventing the agglomeration that typically occurs at high concentrations in single-phase systems.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the physical and chemical parameters at the liquid-liquid interface (interfacial tension, solvent composition) to create optimal conditions for nanoparticle concentration. By adjusting the properties of the two immiscible liquids, the system achieves high nanoparticle concentration while maintaining particle size distribution and preventing agglomeration.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If conventional separation methods are used, then separation is achieved, but the process is slow and not industrially feasible

Engineering Contradiction:
Improveseparation speedVSAvoidprocessing time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent enables continuous operation by preventing nanoparticle adhesion to the centrifuge wall. The liquid-liquid interface system allows the centrifugation process to run continuously without interruption for recovery or cleaning, as nanoparticles remain suspended at the interface rather than forming deposits on the wall.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The liquid-liquid interface serves as a continuous intermediary that maintains nanoparticle suspension and prevents wall adhesion throughout the centrifugation process. This intermediary system allows uninterrupted separation operation, significantly increasing processing speed and making the method industrially feasible.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 achieves high concentration of nanoparticles (up to 1000 times) with minimal agglomeration and efficient recovery, maintaining material functionality by balancing centrifugal force and interfacial tension, suitable for both batch and continuous operations.

Implementation Method 1

centrifuging at a desired rotational speed (rpm) and removing the concentrated metal or metal oxide nanoparticles

Methodology Applied
Scientific EffectCentrifugal separation: Centrifugal Separation

Implementation Method 2

removing the concentrated metal or metal oxide nanoparticles in gel form from the liquid-liquid interface

Methodology Applied
Scientific EffectInterfacial tension: Surface Tension

Data Source

PatentEP3618938B1A process for interfacial separation of metal nanoparticles or nanowires using centrifugal separators
Publication Date: 2024.12.11 COUNCIL OF SCI & IND RES
  • EP3618938B1 patent drawingFigure 1
  • EP3618938B1 patent drawingFigure 2

AI summary

The present invention disclosed a continuous flow and batch process for the separation of metal or metal oxide nanoparticles continuously in a periodic manner at the liquid–liquid interface using a centrifugal separator cum extractor, wherein the nanoparticles are collected at the liquid-liquid interface of the polar and non-polar liquids.