Water scale was obtained from home kitchens in Lianyungang
city, eastern China. All chemicals were of analytical grade and used
as received. Refined soybean oil was procured from local market.
Water waste scale was washed thoroughly with distilled water
several times to remove the impurities and followed by drying in
hot air oven at 105 C for about 24 h. The dried water scales were
subsequently ground to fine powder and calcined in a muffle furnace
at different temperatures ranging from 200 C to 1000 C for
2.5 h to prepare the novel catalysts.