The Heterogeneous SB-SBA-15 Synthesis Technique

2. Materials and methods
2.1. Materials
Analytical grade Fe(NO3)3.9H2O, Na2SO4, NaHCO3, and H2SO4 were obtained from Merck. Reagents such as pluronic acid P123, hydrochloric acid and tetraethylorthosilicate (TEOS) were collected from the Sigma Aldrich and Rhodamine B was purchased from Loba Chemie chemical company. These reagents and dyes were directly used without further purification. Required working volume of RhB dye was made by diluting the prepared 1g/l stock solution. Graphite plates purchased from Anabond Sainergy Limited, Chennai, were used as anode as well as cathode in all electrolytic experiments.
2.2. Synthesis of Fe-SBA-15
The heterogeneous catalyst Fe-SBA-15 was synthesized by wetness impregnation method. The detailed procedure adopted for the synthesis of Fe-SBA-15 and characterization results were previously reported by Sanjini and Velmathi (2014). Ferric nitrate nonahydrate and TEOS were used as iron and silica sources, respectively. The basic mesoporous SBA-15 catalyst support was prepared according to the method previously described by Zhao et al., (1998). The first step was to disperse 4 g of block P123 (EO20PO70EO20) in 40 ml of distilled water and 120ml of 2 M aqueous HCl was added with stirring at 350 C for about 3 h. To this solution, 4 g of TEOS was added and continuously stirred at 400 C for 24h. Then the resulting gel was

The procedure adopted to find the leached concentration of ferrous ions and ferric ions in the electrolyzed RhB solution was already reported by Nidheesh et al. (2014). Reusability of catalyst is one of the major advantages of heterogeneous catalyst (Panda et al., 2011; Zhang et al., 2015). After each experiment, the used catalyst was filtered off and dried at 1050 C for 24 h. This recycled catalyst was utilized for further studies and experiments were conducted at conditions similar to that carried out for the raw