Elettrodeposizione di catalizzatori a base di Rh su schiume e fibre metalliche di FeCrAlloy per la produzione di syngas

Madeddu, Salvatore (2016) Elettrodeposizione di catalizzatori a base di Rh su schiume e fibre metalliche di FeCrAlloy per la produzione di syngas. [Laurea magistrale], Università di Bologna, Corso di Studio in Chimica industriale [LM-DM270], Documento ad accesso riservato.
Documenti full-text disponibili:
[img] Documento PDF
Full-text non accessibile fino al 30 Settembre 2019.
Disponibile con Licenza: Creative Commons Attribuzione - Non commerciale - Non opere derivate 3.0

Download (31MB) | Contatta l'autore

Abstract

The preparation of structured catalysts active in the catalytic partial oxidation of methane to syngas, was performed by electrosynthesis of hydroxides on FeCrAlloy foams and fibers. Rh/Mg/Al hydrotalcite-type compounds were prepared by co-precipitation of metallic cations on the support and successive calcination. Electrochemical reactions have been studied during the electrodeposition by linear sweep voltammetry. The experiments were performed at supports immersed in KNO3, KCl, Mg2+ and Al3+ aqueous solutions, starting by different precursors (nitrate and chlorides salts) and modifying the Mg/A ratio. Rh/Mg/Al hydrotalcite-type compounds were deposited on metal foams by applying a -1.2V vs SCE potential for 2000s with a nitrate solution of 0.06M total metal concentration. Firstly it was studied the effect of Mg on the coating propierties, modifying the Rh/Mg/Al atomic ratio (5/70/25, 5/50/45, 5/25/70 e 5/0/95). Then the effect of the amount of Rh was later investigated in the sample with the largest Mg content (Rh/Mg/Al = 5/70/25 and 2/70/28).The results showed that magnesium allowed obtaining the most homogeneous and well adherent coatings, wherein rhodium was well dispersed. The sample with the Rh/Mg /Al ratio equal to5/70/25 showed the best catalytic performances. Decreasing the Rh content, the properties of the coating were not modified, but the catalytic activity was lower, due to a not enough number of active sites to convert the methane. The work on metal fibers focused on the effect of precursor concentration, keeping constant composition, potential and synthesis time at the values of Rh/Mg/Al =5/70/25, -1.2V vs SCE and 1000s. However fibers geometry did not allow to obtain a high quality coating, even if results were quite promising.

Abstract
Tipologia del documento
Tesi di laurea (Laurea magistrale)
Autore della tesi
Madeddu, Salvatore
Relatore della tesi
Correlatore della tesi
Scuola
Corso di studio
Ordinamento Cds
DM270
Parole chiave
catalizzatori strutturati schiume metalliche fibre metalliche ossidazione parziale catalitica syngas elettrosintesi rodio idrotalciti cella in flusso
Data di discussione della Tesi
11 Ottobre 2016
URI

Altri metadati

Gestione del documento: Visualizza il documento

^