Synthesis and characterization of aerogel/ceramic of silica: anatase: Prussian Blue and nanotinate: Prussian Blue

• Grant number: 19/27265-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2020
• End date: August 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Ubirajara Pereira Rodrigues Filho
• Grantee: Bianca Oliveira Mattos
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The neglected release of alkali metals into the environment by anthropogenic activities is both an environmental issue and an economic issue. At higher concentrations these cations does affect agricultural production and the environment. Many industrial or mining wastes have higher concentration of these ions. For instance, the sugarcane vinasse an industrial waste from ethanol/bioethanol production has higher K+ concentrations, does impaction on its use as a fertilizer over the plantation fields. Thus, its use is limited to prevent nutrients depletion from soil as well as groundwater contamination. In parallel, several mining activities, including brine exploitation, thus generate K+ rich leachates, which can be deleterious to the environment. Aiming to avoid negative impact of these relevant economical activities, it is proposed a new methodology of exploiting these wastes using a hydrometallurgy-inspired approach. This K+ ion selective sorption is a solar driven process using nano-designed heterojunction between Prussian Blue (PB) and anatase. Prussian blue is a well-known material, its synthesis dating from the 19th century, and recently studies of electrosynthesis and photosynthesis have been performed with excellent results. This material has the property of trapping alkali metal cations in its structure when reduced, thus opening the possibility of its use for environmental remediation, waste treatment and hydrometallurgy of these ions. In particular the recovery of potassium ions from mining leachate, brine and vinasse, presents a great possibility of concentrating these ions for later use in agriculture, livestock, ceramics and glass industries. In this project, we intend to use solar UV radiation to stimulate the photoabsorption of these ions by the Prussian blue (PB) grafted on Silica Aerogels@Anatase (ae-SiO2@TiO2), colloidal Silica particles grafted with Nanoparticles of Anatase (SiO2@TiO2) and Nanotitanate (NT). In time, although this specific project does not propose the synthesis of urethanes via CO2 fixation, FAPESP grant # 2018 / 19785-1, it is related to the aims of items 1.2 and 1.3 of the aforesaid project.(AU)