Industrial Consultancy & Sponsored Research (IC&SR) , IIT Madras
Cellulose Nanocrystal Templated Iron Oxyhydroxide Based Adsorbent For Arsenic Removal From Water And A Device Thereof
Technology Category/Market
Category- Micro & Nano Technologies
Industry Classification:
NIC (2008)- 36000 Water collection, treatment and supply; 28195- Manufacture of filtering and purifying machinery or apparatus for liquids and gases.
Applications:
Arsenic Removal from Drinking Water; General Water Purification; remediating contaminated water bodies; sustainable water purification and portable water treatment devices
Market report:
The global Arsenic removal market was valued at USD 684.8 Million in 2023 and is projected to grow to USD 1192.5 Million by 2031, with a CAGR of 5.7%.
Problem Statement
- Arsenic contamination affects over 130 million people globally, with groundwater often polluted, causing a long-standing public health issue due to insufficient affordable removal technologies.
- Existing purification materials face issues like poor separation, leaching, and low hydraulic conductivity, and granulation methods often involve binders or high temperatures, reducing efficiency.
- While chitosan offers a green solution for arsenic removal, its animal origin limits its use. Cellulose nanocrystals (CNCs) provide a sustainable alternative but face scaling challenges.
- There is a need for a sustainable, binder-free granular material for Arsenic removal with improved adsorption and hydraulic conductivity for water purification.
Technology
- The technology involves an iron oxyhydroxide-cellulose nanocrystal composite designed for efficient arsenic adsorption (both As(III) and As(V)) from water, showing high adsorption capacities and low leaching of contaminants (arsenic and iron).
- The composite adsorbs up to 111 mg/g of As(III) and 37 mg/g of As(V) at equilibrium. Arsenic adsorption is significantly influenced by competitive ions, with up to 94% removal observed under optimal conditions.
- Adsorption follows Langmuir isotherms, indicating monolayer adsorption. The maximum adsorption capacity and kinetics were tested with varied arsenic concentrations, showing optimal performance at 298 K, pH 7.0, and 120 min contact time.
- XPS and SEM analyses confirm arsenic binding to surface hydroxyl groups, with arsenic ions transitioning to higher binding energies upon adsorption. The composite maintains structural integrity with minimal change in surface morphology.
- Leachability tests (TCLP) reveal low toxicity, with arsenic and iron leaching below 25 ppb, making the composite safe for long-term environmental use in water purification systems.
Key Features/Value Proposition
- The iron oxyhydroxide-cellulose nanocrystal composite exhibits a superior arsenic removal capacity, adsorbing up to 111 mg/g for As(III) and 37 mg/g for As(V), outperforming traditional adsorbents like activated carbon and alumina in arsenic uptake.
- Unlike many conventional adsorbents, this composite shows efficient arsenic removal even in the presence of competitive ions like CO₃²⁻ and HCO₃⁻, making it suitable for real-world water conditions with high ionic interference.
- TCLP tests demonstrate minimal leaching of arsenic and iron, with levels as low as 2 ppb for arsenic. This makes the composite safer and more environmentally friendly compared to other materials prone to leaching harmful contaminants.
- The synthesis involves a straightforward, room-temperature soft chemistry route, allowing for scalable production of the composite without requiring complex or expensive equipment, making it cost-effective for large-scale water treatment applications.
- The composite’s surface hydroxyl groups efficiently bind arsenic, with minimal alteration in morphology during adsorption. This stability and functionality ensure long-term effectiveness, providing better durability than traditional adsorbents that degrade or lose efficiency over time.
Questions about this Technology?
Contact for Licensing
Research Lab
Prof. T Pradeep
Department of Chemistry
Intellectual Property
- IITM IDF Ref 1433
- IN 343818 Patent Granted
Technology Readiness Level
TRL 4
Technology Validated in Lab