Industrial & Engineering Chemistry Research, Vol.52, No.21, 6956-6961, 2013
Adsorption of Abietic Acid from Colloidal Suspension by Calcined Mg/Al Hydrotalcite Compounds
Resin acids are major constituents of wood extractives and are known to cause a range of paper manufacturing problems including pitch deposition, poor paper machine runnability, and low paper quality. Abietic acid (AA) is one of major constituents of resin acids. Removing AA from colloidal suspension using calcined Mg/Al hydrotalcites (CHTs) was investigated in this study. The removal percentage of AA at the pH value of 6.8 was larger than those at the pH values of 7.8-9.8 and the adsorption capacity was 434.78 mg/g at 323 K. Kinetic data were followed pseudo-second-order kinetic model and adsorption followed the Langmuir isotherm. Adsorption process proceeded by physical adsorption. About 80% of the equilibrium adsorption capacity of the original CHT was achieved after five use cycles. The calcined Mg/Al hydrotalcites exhibited high adsorption capacity for AA and were efficient adsorbents for dissolved and colloidal substances (DCS) in papermaking process.