The linear thermal-expansion coefficients of yttrium silicate Y2SiO5, [Y2(SiO4)O] were measured in the temperature range from 20 to 1400 °C using x-ray diffraction. The anomalous behavior of thermal expansion was observed above Tc = 850 °C and was attributed to the displacive phase transformation. The transformation was reversible and resulted from the local order °C the compositional disorder and local fluctuation in the elastic free energy constrained a secondary transformation related to the polymorphic twin transformation. This created an additional peak in x-ray diffraction patterns at 2 's intensity. The characteristic of phase transformation both on heating and on cooling of the sample was also investigated using the differential thermal analysis method. The thermogravimetric technique did not indicate on a change of weight at Tc.

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Liquid desiccant-based dehumidification with water recovery is an effective and robust method to remove excess moisture from process gas streams and recover relatively high quality product water. A study was undertaken to determine if desiccant-based technology could be applied to the benefit of an amine-based CO 2 capture system since the addition of CO 2 capture to a coal-fired power plant can significantly increase the plant's consumptive water use. Test data with a pilot flue gas moisture recovery system are presented to illustrate the characteristics of the process, including the water recovery potential, product water quality, and thermal energy consumption. The process is then evaluated theoretically under conditions typical of a monoethanolamine-based CO 2 capture process. The analysis indicates that there is less opportunity for moisture recovery compared to a plant without CO 2 capture because of the cooler processing temperatures associated with CO 2 absorption and stripping. However, a desiccantbased dehumidification system might be useful as a heat-driven moisture management tool since desiccant-based moisture removal is more effective than dew point cooling for a given heat rejection temperature. Dehumidifying the CO 2 product stream prior to compression might offer incremental power consumption savings compared to other options of moisture vapor management.

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