Nitrogen-Doped Graphene Oxide for Boron Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for removing boron from aqueous solutions, particularly in semiconductor manufacturing and seawater desalination, are inefficient due to boron's small size and uncharged species at pH 8.4, requiring additional post-treatment processes that are not effective at low concentrations or pH adjustments.
Innovation Solution
A carbon-based boron removal medium comprising nitrogen-doped graphene oxide with hydroxyl groups and nitrogen species, synthesized through a two-step process of graphite oxidation and nitrogen-doping, effectively removes boron by forming stable complexes, and can be regenerated for reuse.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional methods (reverse osmosis, capacitive desalination, electro-dialysis) are used for boron removal, then desalination can be achieved, but boron removal efficiency is poor due to boron's small size and uncharged species at pH 8.4
Solution Approach 1:
The patent modifies the chemical parameters of the adsorbent by nitrogen-doping graphene oxide, introducing pyridinic nitrogen and amine groups that create specific chemical affinity for boron. This chemical modification enables selective boron removal through complexation reactions, overcoming the limitation of conventional physical separation methods that cannot effectively remove uncharged boron species.
Solution Approach 2:
The patent creates a composite material by doping nitrogen into graphene oxide structure, forming N-doped graphene oxide with enhanced boron adsorption capacity. The composite structure combines the high surface area of graphene oxide with the boron-selective binding sites provided by nitrogen functional groups, achieving both high capacity and selectivity for boron removal.
2Reliability
If post-treatment processes (electrocoagulation, chemical precipitation, ion exchange) are applied to remove boron, then boron concentration can be reduced, but additional pH adjustment is required and efficiency remains poor at low concentrations
Solution Approach 1:
The N-doped graphene oxide maintains effective boron adsorption across a wide pH range (pH 2-12) due to the stable chemical affinity between nitrogen functional groups and boron species. This pH independence eliminates the need for pH adjustment steps required by conventional ion exchange and precipitation methods, simplifying the overall treatment process.
3Reliability
If conventional adsorbents are used for boron removal, then some boron can be removed, but adsorption capacity is limited and selectivity is poor
Solution Approach 1:
The nitrogen-doped graphene oxide composite provides high boron adsorption capacity through the synergistic effect of graphene oxide's large surface area and nitrogen functional groups' selective binding capability. The pyridinic nitrogen and amine groups create multiple high-affinity binding sites per unit mass, significantly increasing the amount of boron removed per unit adsorbent compared to conventional adsorbents.
Solution Approach 2:
The patent introduces specific local chemical properties at the nitrogen doping sites on the graphene oxide surface. These localized pyridinic nitrogen and amine groups create high-affinity binding sites that selectively capture boron species, enhancing both capacity and selectivity at specific locations on the adsorbent surface.
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
The nitrogen-doped graphene oxide medium achieves high boron adsorption capacity and selectivity across a wide pH range, including seawater conditions, with efficient regeneration, significantly improving boron removal efficiency and reducing the need for additional treatment steps.
Implementation Method 1
The nitrogen-doped graphene oxide medium achieves high boron adsorption capacity and selectivity across a wide pH range
Data Source
AI summary
In one embodiment, the invention relates to a carbon-based boron removal medium with hydroxyl groups and amine group, and in particular, to a method for forming the carbon-based boron removal medium. In a specific embodiment, nitrogen-doped (“N-doped”) graphene oxide is synthesized by a simple two-step process: (1) oxidation of graphite to graphene oxide, and (2) nitrogen-doping (“N-doping”) the graphene oxide to form the amine group. The resultant N-doped graphene oxide can efficiently remove boron from aqueous solutions. In another embodiment, a method of sensing or detecting the presence of boron in an aqueous solution by using a boron sensing medium comprises at least two hydroxyl groups and at least one pyridinic nitrogen or pyrrolic nitrogen or quaternary nitrogen (i.e. pyridoxine, in particular vitamin B6). The boron ions in the solution would form a highly ionized complex, which can cause significant increase in electrical conductivity of the solution, which can then be used to measure the concentration of boron in said solution.