Adsorbent of nanosized Seaweed-like Sodium Titanate mats for water purification
April 19, 2022
Layered sodium titanate has been used as an adsorbent to filter out pollutants. Its sorption performance can be improved by controlling the chemical composition and crystal structure. Herein we synthesized a “Seaweed-like Sodium Titanate mat (SST)” using a simple hydrothermal process for the purpose of water purification. The nano-structure SST exhibited better performance for capturing cation compared to commercially available material.
As the economic development and the world’s population grows, so will the need for drinkable water.However, many water sources are at risk of contamination by industrial and radioactive waste. he development of water management and water treatment technologies are important for the conservation of water resources. Water pollutants include heavy metals, radionuclides, harmful anions and organic pollutants, and various adsorbents have been proposed for a range of specific pollutants. Among them, sodium titanate with a multilayered structure has been widely used to filter out these pollutants due to its ability to sorb cations in water by ion exchange. Its sorption performance varies depending on the crystal structure and chemical composition. Therefore, the morphological and structural control of the sodium titanate is very important to effectively capture radioactive and/or heavy metal ions. Herein we synthesized a “Seaweed-like Sodium Titanate mat (SST)” by a template-free alkaline hydrothermal process for water purification. Compared with a commercially available material of sodium trititanate, SST, which is the nanostructured sodium dititanate mats, showed improved performance for capturing Sr ions. SST also has potential applications in purification systems for the removal of heavy metals and radionuclides from wastewater and in rare metal recovery.
Mining and metals, Water, Sea
SST, composed of fibrous crystals of sodium dititanate with a linear layered structure, shows higher ion exchange selectivity of other cations such as Co and Sr ions than hydrogen ions (hydronium ions). It therefore has the advantage of being able to efficiently sorb pollutants by ion exchange in water. Another advantage of SST is that it reduces an increase in the pH of the aqueous solution, suppressing the surface precipitation of heavy metal ions, enabling the continuous and more efficient removal of pollutants. Tests conducted using Co and Sr ions have demonstrated that SST show a high sorption capacity close to 2 mmol/g, exhibiting efficient removal of metal cations through ion exchange reaction with Na ions present in the interlayer. Furthermore, SST can also be used as an adsorbent for the recovery of rare elements from industrial wastewater because the sorbed ions are readily released from the interlayer by acidic treatment. Therefore, SST is expected to show excellent functionality in a wide range of applications, including conservation and utilization of water resources and recycling.
Readiness level (TRL)
Proof of concept (TRL 3-4)
There is a joint research partner.
CONDITIONS FOR USE:
R & D contract or research collaboration, License
Research on the implementation of adsorbents on water purification filters in the practical field.
Available technical assistance
State of Development / Opportunity / Seeking:
・Available for exclusive and non-exclusive licensing
・Exclusive/non-exclusive evaluation for defined period (set up for options)
1. Development partner
WIPO GREEN Database Website: