{
    "title": "Graphene Oxide Desalination",
    "inventor_name": "Rahul Nair",
    "publication_year": 2017,
    "device_name": "Graphene Oxide Membrane",
    "goal": "Remove salts and other solutes from water to produce potable or purified water.",
    "problem_addressed": "Lack of access to clean drinking water and the need for efficient desalination of seawater and wastewater.",
    "concept_summary": "A graphene-oxide laminate membrane, cross-linked and optionally combined with graphene flakes, is engineered to limit swelling in water, allowing precise control of pore size. The membrane acts as a size-exclusion filter that rejects ions (e.g., NaCl) while permitting high water flux, enabling scalable desalination.",
    "detailed_description": null,
    "category": "Materials Science & Ceramics",
    "principles": [
        "Size-exclusion filtration",
        "Control of membrane swelling through cross-linking",
        "Tunable pore size via cross-linking agents and graphene inclusion",
        "Hydration-radius based ion rejection"
    ],
    "scientific_domains": [
        "Materials Science",
        "Chemical Engineering",
        "Environmental Engineering",
        "Nanotechnology"
    ],
    "mechanisms_of_action": [
        "Selective ion rejection based on hydration radius",
        "Reduced pore expansion upon hydration due to cross-linking",
        "Enhanced water permeability through thin GO laminates"
    ],
    "materials": [
        "graphene oxide",
        "graphene",
        "cross-linking agents",
        "graphene oxide flakes",
        "graphene flakes"
    ],
    "energy_sources": [],
    "inputs": [
        "seawater",
        "contaminated water",
        "aqueous mixtures containing salts or other solutes"
    ],
    "outputs": [
        "purified water",
        "desalinated water",
        "water with reduced solute concentration"
    ],
    "claimed_performance": "97% NaCl rejection; water flux 6-10 L m^-^2 h^-^1 bar^-^1 at 25 bar (vs ~2 L m^-^2 h^-^1 bar^-^1 for non-cross-linked GO membranes).",
    "experimental_evidence": "Laboratory tests showed 97% rejection of NaCl and a water flux of 6-10 L m^-^2 h^-^1 bar^-^1 for cross-linked GO membranes at 25 bar pressure.",
    "replication_status": "Demonstrated in laboratory experiments; no commercial scale deployment reported.",
    "keywords": [
        "graphene oxide",
        "membrane filtration",
        "desalination",
        "cross-linking",
        "nanofiltration",
        "water purification"
    ],
    "related_technologies": [
        "reverse osmosis",
        "nanofiltration",
        "membrane distillation"
    ],
    "controversy_level": "low",
    "confidence_score": 0.9,
    "practicability_score": 0.6,
    "fringe_score": 0.1,
    "evidence_strength": 0.7,
    "risk_score": 0.1,
    "trl_estimate": 5,
    "source_urls": [
        "http://www.ibtimes.co.uk/graphene-sieve-turns-seawater-into-clean-drinking-water-technology-can-be-scaled-1615113",
        "https://www.nature.com/articles/nnano.2017.21.epdf",
        "WO2016189320"
    ],
    "organizations": [
        "University of Manchester",
        "Pacific Northwest National Laboratory",
        "European Patent Office"
    ],
    "applications": [
        "drinking water production",
        "industrial wastewater treatment",
        "brackish water desalination"
    ],
    "limitations": [
        "Scalable, cost-effective production of GO membranes",
        "Membrane fouling by organics, salts and biological material",
        "Long-term mechanical stability under continuous operation"
    ],
    "open_questions": [
        "What is the optimal cross-linking agent for durability and flux?",
        "How does membrane performance evolve over months/years of operation?",
        "Can manufacturing costs be reduced to compete with existing desalination technologies?"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "We demonstrate a simple scalable method to obtain graphene-based membranes with limited swelling, which exhibit 97% rejection for NaCl.",
        "The cross-linked GO laminate membranes used in the methods of the invention are between 6 and 10 L m^-^2 h^-^1 bar^-^1 with 25 bar pressure.",
        "Graphene oxide membranes swell in water, causing larger salt ions or molecules to be blocked out.",
        "By including cross-linking agents or graphene in GO laminate membranes, the expansion of the pores which usually occurs on hydration is reduced."
    ]
}