Removal of aliphatic organic acids from the wastewater by using adsorbents obtained from buffalo droppings

The buffalo droppings were chemically modified with acids and bases, and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, surface area, and Fourier-transform infrared spectroscopy analysis. The raw and treated dropping samples were then used as adsorbents for the removal of aliphatic organic acids including formic acid, acetic acid and propanoic acid from their aqueous solutions. The adsorption was studied at different temperatures, that is, 20 degrees C, 30 degrees C, and 40 degrees C, and different time durations ranging from 0.5 to 8 h. The adsorption kinetics was investigated and various thermodynamic parameters were determined such as activation energy, free energy, enthalpy, and entropy, etc. The results were also interpreted using different adsorption models including Bhangham, Elovich, and intraparticle diffusion.