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The kinetics of phenol adsorption from aqueous solution on activated carbons (ACs) obtained from coffee husk by potassium Hydroxide (KOH) activation at 650 and 750^oC have been studied in the range of     100-250 mg L^-1 initial phenol concentrations and at the temperatures range of 10 – 40^oC. Kinetic models for phenol adsorption were evaluated using pseudo-first-order, pseudo-second-order, and Elovich models. The adsorption mechanism was investigated using Reichenberg, Boyd, and Weber and Morris models. The adsorption on coffee husk activated carbon was found to be a fast or speedy process with the adsorption rate, k₂q_e, in the range of 0.130 to 0.977 min^-1. The adsorption process was mainly physical and promoted by chemical sorption and controlled not only by intra-particle diffusion but also by pore diffusion throughout the entire adsorption period.

Activated carbons (ACs) obtained from coffee husk by KOH activation at 650 (ACK-650) and 750 o C (ACK-750), were used as an adsorbent for the adsorption of phenol from aqueous solution. The ACs was characterized by SEM, EDX, BET, and Boehm titration techniques. The experimental equilibrium data of phenol adsorption was analyzed by eight isotherm models, which are four two-parameter equations (Langmuir, Freundlich, Elovich, and Temkin) and four three-parameter equations (Redlich-Peterson, Sips, Radke-Prausnitz, and Tóth). The results reveal that in general, three-parameter isotherms can provide better prediction than two-parameter isotherms. The best fit for ACK-650 sample is Sips isotherm, while for ACK-750 sample is Redlich-Peterson isotherm. Isosteric heat and thermodynamic parameters ΔG o , ΔH o , and ΔS o of the adsorption were determined, and the results showed that the adsorption of phenol was exothermic and physical in nature. A scale-up of a batch system is designed for 2 to 10 L phenol with an initial concentration of 100 mg L -1 .

Two 4-substituted 2,2'-bipyridines, namely 4-(ferrocenylethynyl)-2,2'-bipyridine (I) and 4-ferrocenyl-2,2'-bipyridine (II) have been synthesized and fully characterized via single-crystal X-ray diffraction and 1 H and 13 C NMR analyses. The π-conjugated system designed from 2,2'-bipyridine modified with the ferrocenylethynyl and ferrocenyl groups shows the desired planarity. In the crystal packing of I and II, the molecules arrange themselves in head-to-tail and head-to-head motifs, respectively, resulting in consecutive layers of ferrocene and pyridine moieties.