Synthesis cellulose fluorescent hydrogel from agroindustrial residue: removal and sensing of toxic metals and pesticides from water

• Grant number: 22/13124-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2023
• End date: August 31, 2027
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Carlos José Leopoldo Constantino
• Grantee: Andressa Silva Gomes
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil
• Associated scholarship(s): 24/04096-7 - CELLULOSE-BASED HYDROGELS OBTAINED FROM DIFFERENT BIOMASS SOURCES: STUDY OF THE FORMATION MECHANISM AND APPLICATION ON TOXIC METAL REMOVAL FROM WATER, BE.EP.DR

Abstract

Water is a resource intrinsically related to our survival and maintenance of productive activities that is largely wasted and subject to increasingly varied contamination, from toxic metals to so-called emerging contaminants. This class includes drug residues, dyes, hormones, caffeine, herbicides, and pesticides. These have been the subject of scientific concern for being persistent and difficult to degrade when released into the environment. It is proven that the permanence of these contaminants in the environment causes an imbalance in the biota and a risk to human health beings. Considering that conventional methods for water treatment are not entirely effective to eliminate all these contaminants, the distribution of water is subject bound to be less safe. In this context, hydrogels have been shown to be potential materials for the removal of emerging contaminants due to their high confinement capacity in their 3D network. Furthermore, it is possible to associate the polymeric network of the hydrogel with the properties of carbon quantum dots (CDs) that can indicate the presence of the target contaminant by the variation of fluorescence intensity emitted, being possible to apply them to contaminants' detection. As a complementary measure, there is the possibility of identification the absorption band by UV-Vis absorption spectroscopy. In this context, the project proposes to synthesize the hybrid hydrogel based on cellulose and lignin, both isolated from sugarcane bagasse, with carbon quantum dots (CDs) synthesized in situ to remove and detect toxic metals and emerging contaminants together with subsequent identification via fluorescence. Being chosen for this work: (i) lead ions (Pb2+), hexavalent chromium (Cr6+) and mercury (Hg2+), potentially mutagenic and carcinogenic metals listed as highly dangerous in the world, and (ii) glyphosate herbicide, the most used in Brazil and in the world. This project is linked to the Laboratory of Biosystems (LBs) (Autos n° 98.1201665-7) and a 12-month internship is foreseen through the BEPE scholarship (Stony Brook University, NY, EUA). (AU)