Tomohito Kameda

We found that activated carbon effectively removed urea from solution and that urea adsorption onto activated carbon followed a pseudo-second-order kinetic model. We classified the urea adsorption on activated carbon as physical adsorption and found that it was best described by the Halsey adsorption isotherm, suggesting that the multilayer adsorption of urea molecules on the adsorption sites of activated carbon best characterized the adsorption system. The mechanism of adsorption of urea by act

A Mg–Al layered double hydroxide (Mg–Al LDH) has been modified with aromatic anions by a coprecipitation technique. This method is based on the anion-exchange characteristics of the hydrotalcite-type compound which intercalates various anions, including anions of organic acids, in the interlayer. The Mg–Al LDHs are intercalated with 2-naphthalene sulphonate (2-NS−) and 2,6-naphthalene disulphonate (2,6-NDS2−) ions, which contain a naphthalene ring with one and two sulphonate (–SO3−) groups in th

Abstract The removal of hydrochloric acid utilizing magnesium-aluminum oxide (Mg–Al oxide), as prepared by the thermal decomposition of hydrotalcite (HT), was investigated. Cl− in hydrochloric acid can be removed almost 100% by adding 1.75 times the stoichiometric quantity of Mg0.70Al0.20O at 60 °C for 1 h. Mg2+ and Al3+ in solution after the reaction were not recognized, because the solution was weakly alkaline.

Abstract Magnesium-aluminum oxide (Mg-Al oxide) was shown to be superior to CO32- intercalated hydrotalcite (CO3-HT) for removing dilute hydrochloric acid. Cl- in a 0.5 M HCl solution could be quantitatively removed by adding 1.75-times the stoichiometric quantity of Mg0.70Al0.20O at 60 °C for 1 h. The solution after the reaction was weakly alkaline. This reaction could be adequately described as being first order for the HCl concentration, and the apparent activation energy was 49.3 kJ mol-1. T