Figure 6 | Scientific Reports

Figure 6

From: Nano-synthesis of solid acid catalysts from waste-iron-filling for biodiesel production using high free fatty acid waste cooking oil

Figure 6

XRD patterns of (a) α-\({\text{Fe}}_{2} {\text{O}}_{3}\), (b) RBC500, (c) RBC700, and (d) RBC900. Chemical compounds in the products: (1) Hematite—α-\({\text{Fe}}_{2} {\text{O}}_{3}\). (2) Aluminum hydrogen sulfate hydrate—\({\text{AlH}}\left( {{\text{SO}}_{4} } \right)_{2} \cdot {\text{H}}_{2} {\text{O}}\). (3) Rhomboclase—\(\left( {{\text{H}}_{5} {\text{O}}_{2} } \right){\text{Fe}}\left( {{\text{SO}}_{4} } \right)_{2} \left( {{\text{H}}_{2} {\text{O}}} \right)_{2}\). (4) Coquimbite—\({\text{Fe}}_{1.68} {\text{Al}}_{.32} \left( {{\text{SO}}_{4} } \right)_{3} \left( {{\text{H}}_{2} {\text{O}}} \right)_{9}\).

Back to article page