Forward Osmosis Draw Solute With Tunable Phase Separation
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Solution Overview
Problem
The existing forward osmosis membrane process lacks a diverse range of draw solutes, limiting the selection of optimal solutions for various applications.
Innovation Solution
The use of an addition polymer obtained by polymerizing an alkylene oxide with 2 to 10 carbon atoms to an amine compound, particularly polyethyleneimine, as a draw solute, which can be tailored with specific molecular weights and alkylene oxide ratios to enhance osmotic pressure and phase separation properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If existing draw solutes are used in forward osmosis membrane process, then the process can operate, but the selection scope is limited and cannot be optimized for various applications
Solution Approach 1:
The patent applies parameter changes by systematically varying the molecular weight of polyethyleneimine (from 200 to 2000 g/mol) and the degree of propylene oxide addition (from 0.5 to 10 moles per amine group) to create a series of draw solutes with different osmotic pressures and phase separation temperatures, enabling optimization for various forward osmosis applications
Solution Approach 2:
The patent creates composite draw solutes by combining polyethyleneimine with propylene oxide through addition polymerization, forming a new class of temperature-sensitive absorbent materials that exhibit both high osmotic pressure and controllable phase separation properties, expanding the available draw solute options
2Productivity
If a draw solution with high osmotic pressure is used to move water through the membrane, then water treatment efficiency is improved, but the draw solute must also allow easy separation of solvent which limits the choices
Solution Approach 1:
The patent utilizes phase transitions by designing draw solutes that undergo temperature-induced phase separation, where the polyethyleneimine-propylene oxide complexes precipitate at elevated temperatures, enabling easy separation of the draw solute from the purified water and facilitating continuous operation
Solution Approach 2:
The patent changes the physical state parameter of the draw solute by controlling the phase separation temperature through selection of appropriate polyethyleneimine molecular weight and propylene oxide addition amount, allowing optimization of both water treatment efficiency and solvent separation ease
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 provides a suitable draw solute for forward osmosis membrane processes, enabling efficient water treatment and energy savings by optimizing osmotic pressure and facilitating continuous operation through phase separation of the draw solute and solvent.
Implementation Method 1
A forward osmosis membrane process utilizes a phenomenon in which a solvent moves from the side with lower osmotic pressure to the side with higher osmotic pressure by bringing two solutions having different concentrations into contact with each other via a semipermeable membrane
Implementation Method 2
an addition polymer obtained by addition polymerization of an alkylene oxide having 2 to 10 carbon atoms to an amine compound
Implementation Method 3
facilitating continuous operation through phase separation of the draw solute and solvent
Data Source
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AI summary
A draw solute for forward osmosis membrane process, comprising an addition polymer obtained by addition polymerization of an alkylene oxide having 2 to 10 carbon atoms to an amine compound.