UV-Based Advanced Oxidation Processes of Remazol Brilliant Blue R Dye Catalyzed by Carbon Dots

• Published in: Nanomaterials (Basel, Switzerland) Vol. 12; no. 12; p. 2116
• Main Authors: Cardoso, Inês M. F., Cardoso, Rita M. F., Pinto da Silva, Luís, Esteves da Silva, Joaquim C. G.
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 20.06.2022; MDPI
• Subjects: Anthraquinone; Anthraquinone dyes; Azo dyes; Carbon; Carbon dots; Catalysts; Chemical synthesis; Decomposition reactions; Degradation; Discoloration; Dyes; Ethylenediamine; Hydrogen peroxide; Nanomaterials; Orange II; Oxidation; Polyethylene glycol; Precursors; Rate constants; reactive blue 19; Remazol Brilliant Blue R; Sodium salts; textile dyes; Titanium; Titanium dioxide; UV based AOP; St Louis Missouri; United States > US
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano12122116

UV-based advanced oxidation processes (AOPs) (UV/H2O2 and UV/S2O82−) with a titanium(IV)-doped carbon dot, TiP-CD, as a catalyst were developed for the decomposition of Remazol Brilliant Blue R (Reactive Blue 19), an anthraquinone textile dye (at T = 25 °C and pH = 7). The Ti-CD, with marked catalytic UV properties, was successfully synthesized by the one-pot hydrothermal procedure, using L-cysteine as carbon precursor, ethylenediamine as nitrogen source, PEG (polyethylene glycol) as a capping agent, and titanium(IV) isopropoxide (precursor of TiO2 doping). Contrary to azo dyes (methyl orange, orange II sodium salt, and reactive black 5), which achieved complete degradation in a time interval less than 30 min in the developed AOP systems (UV/H2O2, UV/S2O82−, and UV/TiO2), the RBB-R showed relatively low degradation rates and low discoloration rate constants. In the presence of the catalyzer, the reaction rate significantly increased, and the pseudo-first-order rate constants for the RBB-R discoloration were UV/3.0 mM H2O2/TIP-CD-0.0330 min−1 and UV/1.02 mM S2O82−/TIP-CD-0.0345 min−1.