Development of Novel Synthetic Amine Absorbents for CO2 Capture

AbstractIn the present paper, we investigated five synthetic amine based absorbents, including three formulated solvents. Aqueous solutions of the amines (mass fraction; 30% for single amine and >30% for blended solvents) were used to evaluate the performance for CO2 capture. Gas scrubbing, vapor-liquid equilibrium (VLE), and reaction calorimetry experiments were conducted in the laboratory to obtain the absorption rate, the amount of CO2 absorbed, cyclic CO2 capacity, and heat of reaction for each absorbent. The results of these absorbents were compared with the conventional absorbent monoethanolamine (MEA). Three high performing synthetic absorbents (IPAE, IPAP and IBAE) were found, and these had lower heats of reaction, higher cyclic capacities, and comparable absorption rates compared with MEA. All formulated absorbents showed excellent cyclic CO2 capacity and keeping moderately good absorption rate and lower heats of absorption. Some blended solvents were already demonstrated with real blast furnace gas at pilot test plants with capacities of 1 ton-CO2/day and 30 ton-CO2/day and showed promising results in terms of reducing absorbent regeneration energy

Magnetic-Field-Independent Ultrasonic Dispersions in the Magnetically Robust Heavy Fermion System SmOs4Sb12

Elastic properties of the filled skutterudite compound SmOs$_4$Sb$_{12}$ have been investigated by ultrasonic measurements. The elastic constant $C_{11}(\omega)$ shows two ultrasonic dispersions at $\sim$15 K and $\sim$53 K for frequencies $\omega$ between 33 and 316 MHz, which follow a Debye-type formula with Arrhenius-type temperature-dependent relaxation times, and remain unchanged even with applied magnetic fields up to 10 T. The corresponding activation energies were estimated to be $E_2$ = 105 K and $E_1$ = 409 K, respectively. The latter, $E_1$, is the highest value reported so far in the Sb-based filled skutterudites. The presence of magnetically robust ultrasonic dispersions in SmOs$_4$Sb$_{12}$ implies a possibility that an emergence of a magnetically insensitive heavy fermion state in this system is associated with a novel local charge degree of freedom which causes the ultrasonic dispersion.Comment: 5 pages, 4 figure