Functionalization of sewage sludge char by partial oxidation with molecular oxygen to enhance its adsorptive properties
| Autor: | María Atienza-Martínez, Hans-Heinrich Carstensen, Nurull Nadia Binti Suraini, Javier Ábrego, Gloria Gea, Isabel Fonts, Luisa Lázaro |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Renewable Energy
Sustainability and the Environment 020209 energy Strategy and Management 05 social sciences 02 engineering and technology Industrial and Manufacturing Engineering chemistry.chemical_compound Adsorption chemistry Chemical engineering Specific surface area 050501 criminology 0202 electrical engineering electronic engineering information engineering Sewage treatment Ammonium Limiting oxygen concentration Partial oxidation Char Sludge 0505 law General Environmental Science |
| Zdroj: | Zaguán. Repositorio Digital de la Universidad de Zaragoza instname |
| Popis: | This study investigates the activation of sewage sludge char through partial oxidation with molecular oxygen with the goal to increase the concentration of oxygen-containing surface functional groups and to enhance its ammonium adsorption capacity. The effects of oxidation temperature (200–350 °C), oxygen concentration (5–21 vol %) and oxidation time (30–120 min) on the degree of char oxidation are analyzed. The results obtained by thermogravimetric and elemental analysis, and Fourier Transform Infrared and X-ray Photoelectron spectroscopy corroborate the incorporation of oxygenated functional groups on the surface of sewage sludge char either at low temperature (200 °C) using air or at higher temperature (350 °C) using 5% O2 for 30 min. The oxidation of sewage sludge char hardly increases its specific surface area. The operating conditions during oxidation must be carefully controlled to avoid runaway reactions that lead to total oxidation of char. The evolution of CO and CO2 during oxidation is a good indicator of the advance of the oxidation/burn-off reactions. The ammonium adsorption capacity of sewage sludge char increases after oxidation under mild operating conditions, providing support to the idea of onsite utilization of sewage sludge as ammonium adsorbent in waste water treatment plants. This would provide a step forward towards the implementation of a circular economy. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|