Adsorption of H2O and Dimethyl Carbonate at High Pressure over Zeolite 3A in Fixed Bed Column

Sorption enhanced dimethyl ether synthesis under industrially relevant conditions: experimental validation of pressure swing regeneration

High single-pass production of dimethyl ether from CO₂-rich feedstock is demonstrated by pressure swing regeneration, allowing enormous increase in productivity.

Adsorption Characteristics of Bixin on Acid- and Alkali-Treated Kaolinite in Aprotic Solvents

The adsorption of bixin in aprotic solvents onto acid- and alkali-treated kaolinite was investigated. Kaolinite was treated three times, for 6 h each, with 8 M HCl or 5 M KOH. The adsorbents were characterized by XRD, FT-IR, EDS, and BET-N₂. The effects of contact time and dye concentration on adsorption capacity and kinetics, electronic transition of bixin before and after adsorption, and also mechanism of bixin-kaolinite adsorption were investigated. Dye adsorption followed pseudo-second order kinetics and was faster in acetone than in dimethyl carbonate. The best adsorption results were obtained for KOH-treated kaolinite. In both of the solvents, the adsorption isotherm followed the Langmuir model and adsorption capacity was higher in dimethyl carbonate (q_m = 0.43 mg/g) than in acetone (0.29 mg/g). The adsorption capacity and kinetics of KOH-treated kaolinite (q_m = 0.43 mg/g, k₂ = 3.27 g/mg·min) were better than those of HCl-treated kaolinite (q_m = 0.21 mg/g, k₂ = 0.25 g/mg·min) and natural kaolinite (q_m = 0.18 mg/g, k₂ = 0.32 g/mg·min). There are shift in the band position of maximum intensity of bixin after adsorption on this adsorbent. Adsorption in this system seemed to be based essentially on chemisorption due to the electrostatic interaction of bixin with the strong basic and reducing sites of kaolinite.

Direct synthesis of dimethyl carbonate from CO2 and methanol over CaO–CeO2 catalysts: the role of acid–base properties and surface oxygen vacancies

The addition of CaO to the CeO₂ catalyst had a significant impact on the acid–base properties and amounts of oxygen vacancies on the surface catalyst.

Dimethyl carbonate synthesis from carbon dioxide using ceria–zirconia catalysts prepared using a templating method: characterization, parametric optimization and chemical equilibrium modeling

In this paper, a series of Ce_xZr_1−xO₂ solid solution spheres were synthesized by exo- and endo-templating methods and tested for dimethyl carbonate (DMC) synthesis using direct conversion of CO₂.