Adsorption kinetics and thermodynamics of hydroquinone with aid of diatomite-modified wood ceramics

Diatomite-modified wood ceramics (DMWCs) were successfully prepared to remove hydroquinone from waste-water. The adsorption kinetics and adsorption thermodynamics of DMWCs on hydroquinone were comprehen-sively studied. The results indicate that the prepared DMWCs with the porous structure are composed of quartz and crystalline graphite. When the hydroquinone dosage is 200 mg and the pH is 7, the removal rate and adsorption capacity of DMWCs reach 76.8% and 12.31 mg/g, respectively. Among the fitting parameters under different pH conditions, the correlation coefficient (R2 = 0.99) of the pseudo-second-order kinetic model is larger than the fitting results of other models, displaying a better fitting effect on the adsorption process of hydro-quinone. At different temperatures, the Freundlich equation, Redlich-Peterson equation and Koble-Corrigan equation are all well fitted to the adsorption isotherm data with the correlation coefficients R2 higher than 0.93. The regeneration test shows that the elimination rate of hydroquinone remains above 73% after reuse for 11 times. This study provides a newly available adsorbent of DMWCs to remove hydroquinone from wastewater effectively.