Reduction of Fe(III) in a high-iron saponite. Pillaring of the reduced samples with Al13 oligomers
Abstract:A high-iron content saponite, of the variety griffithite, was reduced using sodium dithionite and hydrazonium sulphate solutions. An important amount of Fe3+ was reduced during the treatments. When using sodium dithionite as reducing agent, the reduction was accompanied by the substitution of Ca2+ by Na+ as the exchangeable cation. When using hydrazonium sulphate, the reduction was accompanied by acid activation of the clay, the protons being released in the oxidation reaction of the hydrazonium cation. The charge balance in the clay layers is affected by the reduction processes. These structural changes do not significantly affect the pillaring ability of the clay, which is similar in the reduced solids and in the natural griffithite.
Document Type: Research Article
Affiliations: 1: Area de Mineralogia, y Cristalografia, DeDepartmento de Geologia, Universidad de Salamanca, Plaza de la Mercced S/N, 37008=Salamanca, Spain 2: Area de Mineralogia, y Cristalografia, Departmento de Geologia, Universidad de Salamanca, Plaza de la Mercced S/N, 37008=Salamanca, Spain
Publication date: June 1, 1998