Synthesis, characterization and acid catalysis of solid acid from peanut shell

• A strong solid acid was prepared from peanut shell.
• The structure of the solid acid was characterized in detail.
• The functional groups on the solid acid were clearly revealed.
• It exhibits excellent catalytic activity and recyclability in biodiesel production.

A strong Brønsted solid acid was synthesized by sulfonation of the partially carbonized agricultural biowaste peanut shell. The acidity of the Brønsted solid acid was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectra (FT-IR) and solid-state nuclear magnetic resonance (NMR) spectroscopy. The characterization results show that sulfonation on the peanut shell carbon produces a carbon based solid acid containing three functional Brønsted acid sites: weak acidic OH groups, strong acidic COOH and SO3H groups. The acid strength of the solid acid is stronger than that of HZSM-5(Si/Al = 75), but still weaker than that of 100% H2SO4. The catalytic reaction tests indicate that this solid acid catalyst exhibits high activity and excellent recyclability for biodiesel production.

A strong solid Brønsted acid was synthesized by sulfonation of the partially carbonized peanut shell. The structure and acidity of the solid acid were characterized by XRD, FT-IR and solid state NMR. The solid acid catalyst exhibits high activity in biodiesel production reaction and the spent solid acid can be recovered by easy operation.Figure optionsDownload high-quality image (254 K)Download as PowerPoint slide