Publication Type:

Journal Article


Journal of Hazardous Materials, Volume 161, Number 2–3, p.1313 - 1322 (2009)



Process design


Batch and continuous experiments were performed for the sorption of distillery spent wash onto fly ash particles. The Freundlich and pseudo-second order equation were found to fit the equilibrium data perfectly. The Weber–Morris intraparticle diffusion isotherm equation was used to predict the sorption mechanism and the predicted equation for 10% dilution of spent wash sorption is qt = 1.1344t0.5 + 33.304. The optimization using 23 factorial design of experiments provides optimal removal of color of 93% for dilution (5%), dosage of adsorbent (10 g) and temperature (293 K). The actual color removal at optimal conditions was 92.24%, confirms close to the factorial design results. The complete error analysis using six non-linear error functions: Chi-square (χ2); sum of square errors (SSE); composite fractional error function (HYBRD); derivative of Marquardt's percent standard deviation (MPSD); average relative error (ARE); sum of absolute errors (EABS) were calculated. Free energy of adsorption at 293 K (ΔG0 = −1574.67 J), enthalpy change (ΔH0 = −32.5487 KJ) and entropy change (ΔS0 = 105 J/K) were calculated to predict the nature of adsorption. Adsorption studies in a packed column were evaluated using Bed depth service time model, Thomas model and Adams–Bohart model.

Cite this Research Publication

K. R. Prasad and Srivastava, S. N., “Sorption of distillery spent wash onto fly ash: Kinetics, mechanism, process design and factorial design”, Journal of Hazardous Materials, vol. 161, pp. 1313 - 1322, 2009.