Absorbent microcapsules for anionic species
Tutor / Supervisor
Student
Aymerich Cugat, Núria
Document type
Master thesis
Date
2024
rights
Open Access
Publisher
Universitat Politècnica de Catalunya
UPCommons
Abstract
A bio-based approach for the removal of anionic dyes from aqueous media has been explored through the development of cellulose derivative particles capable of effectively removing anionic dyes after the dyeing process from both fabric surfaces and water environment. This innovation focuses on reducing the number of wash cycles required for fabrics and obtaining non-contaminated water, thereby addressing significant environmental concerns associated with textile dyeing. These particles were synthesized by bonding microcrystalline cellulose (MC) with chitosan using 1,4-cyclohexanedicarboxylic acid (CHDCA) as a crosslinker. This crosslinker reacts with both biopolymers via esterification or amidation reactions, enhancing the stability and functionality of the resulting compounds. The reaction parameters were studied by varying the cellulose ratio and optionally adding a surfactant (Tween 20) to reduce the surface tension during the reaction, resulting in better yields. The resulting solids were characterized using two advanced techniques: Fourier-transform infrared spectroscopy (FT-IR spectroscopy) and Thermogravimetric analysis (TGA), which confirm the success of the reaction and reveal the thermal stability of the obtained structures. To assess the ability of the synthesized compounds to absorb anionic dyes, each solid was mixed with aqueous solutions containing either Direct Red 89 or SOLAR BL 150, both anionic dyes. After a period of contact, the remaining soluble dye concentration was determined by ultraviolet-visible spectroscopy (UV-Vis). The dye retention percentage was calculated, showing promising preliminary results that indicate the effectiveness of these cellulose derivative particles. Additionally, the study was extended to a cationic dye, Basic Blue 3, to evaluate the potential versatility of the particles in interacting with different dye types and expanding their applications in wastewater treatment
