Development of All-Cellulose Ultrafiltration Membranes for High-performance Wastewater Treatment

Background

Previous studies on the membranes for wastewater treatment have predominantly involved the use of synthetic polymers such as polyvinylidene fluoride (PVDF), polyethersulfone (PES), polysulfone (PS), and polyacrylonitrile (PAN). All‑cellulose membranes, developed entirely from natural biomass resources, have untapped potentials for a wide range of water purification applications, including wastewater treatment. Using cellulose/nanocellulose in membrane preparation demonstrates many beneficial properties such as enhancement of membrane sustainability, change of membrane hydrophilicity, greater permeability/selectivity, and notable resistance to biofouling. However, several bottlenecks remain for the fabrication of all‑cellulose membranes regarding the preparation methods, dependence of supporting substrates, and the usage of organic solvent.

Technology

Researchers at Stony Brook University (SBU) have developed a cellulose membrane and method of preparing the membrane for wastewater treatment with low fouling. Using 100% sustainable cellulose, the membrane is manufactured by a simple and energy‑saving preparation. The method provides a low‑cost, sustainable, and water‑resistant all‑cellulose membrane in one‑step without pressurization or any usage of organic solvent. The membrane is hydrophilic but demonstrates water‑resistance and high porosity (~80%). Additionally, the system shows good mechanical strength, pH resistance, stability in hot water, high permeation flux (8.8 ± 1.5 L/m2 h psi), excellent separation efficiency (>99.9%), good flux recovery ratio (>95%), and self‑healing property for wastewater filtration. These characteristics provide superior filtration performance compared to commercially available membranes. Thus, this technology illustrates the promising potential of using all‑cellulose membranes for high‑efficient wastewater treatment and its superior antifouling abilities.

Advantages

Cost‑effective - Sustainable - High porosity (~80%) - High permeation flux (8.8 ± 1.5 L/m2 h psi) - Good flux recovery ratio (>95%) - Excellent separation efficiency (>99.9%) - Can be prepared in one step without pressurization or any usage of organic solvent - Stability - Self‑healing property - Flexibility and ductility