Integrated system for in situ generation and online monitoring of H2O2: Coupling an electrochemical flow reactor to a flow injection analysis system

Author(s)

Santos, Anderson M. ; Souto, Robson S. ; Barros, Willyam R. P. ; Lanza, Marcos R. V.

• Document type: Journal article
• Source: PROCESS SAFETY AND ENVIRONMENTAL PROTECTION; v. 198, p. 9-pg., 2025-04-15.

Abstract

In this study, we investigated for the first time the coupling of an electrochemical flow reactor (EFR) with gas diffusion electrode (GDE) for the in-situ hydrogen peroxide (H2O2) electrogeneration and real-time detection of using a flow injection analysis (FIA) system. In the FIA setup, we employed a screen-printed electrode (SPE) for monitoring H2O2 using 0.050 mol L-1 K2SO4 as supporting electrolyte at pH approximate to 6.5. After optimizing the operational parameters, the system recorded a high degree of precision for H2O2 detection over a concentration range of 1.0-400 mg L-1, reaching a limit of detection of 0.30 mg L-1. The EFR-GDE system was efficiently tested for H2O2 generation in single-pass and recirculating modes at different current densities under 30 L h-1 flow rate and 100 mL min-1 O2(g) flow rate. The FIA system coupled to the EFR-GDE under single-pass mode was effective in determining/monitoring H2O2 generation under different conditions. This coupling approach addresses limitations in conventional H2O2 monitoring techniques, offering a practical solution for decentralized, on-demand applications, and serves as a potential reference for scalable commercial use. (AU)

• FAPESP's process: 19/06650-3 - EMU granted in the 2017/10118-0 process: potentiostat system with impedance module
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 23/14335-6 - Development of disposable electrochemical sensors for the determination and online monitoring of emerging contaminants in degradation processes
• Grantee: Anderson Martin dos Santos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/22210-0 - EMU granted in process 2017/10118-0: liquid chromatograph (HPLC)
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 22/12895-1 - Advanced processes for the degradation of emerging pollutants: catalytic materials, electroanalytical sensors and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants