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Improving the steam reforming of ethanol by Ni/Al2O3/CaO composite was investigated in this work. The CO2 sorbent plays a key role in the catalytic reaction enhancement. The reforming catalysts were prepared by the as-prepared 10 wt.% Ni/Al2O3 physical mixing with CaO sorbents (from Ca(OH)2 conversion). All reforming experiments were performed under 873K condition. In addition, the suitable parameters of mass ratio of Ni catalyst/CO2 sorbent (20 : 80 w/w) and steam / ethanol molar ratio of five were adjusted in this work. The results indicate that the steam reforming of ethanol via CO2 sorption enhancement obviously produced ∼95% H2 greater than common steam reforming of ethanol (∼72% H2). Other by-products involving CO2, CO and CH4 can be also obviously suppressed during reaction. For the sorption-enhanced steam reforming, the recyclability of CO2 sorbent is an important issue. The 10 cycles of reaction/regeneration at 873K and 1023K for the steam reforming of ethanol were tested. The results reveal the H2 concentration of products stably keeps above 90% during the cycles test. The performance of CO2 sorbent was insignificant change after 10 cycles. The average capture capacity of CO2 around 17.8 wt.% can be determined during cycles.

We have demonstrated a unique scheme for electronically steering an acoustic beam over an angle large than 70° in a TeO2 crystal. The idea is based on the principle that the acoustic energy flow direction is always normal to the slowness curve in an acoustically anisotropic crystal. In the plane normal to the c axis of a TeO2 crystal and around the (110) axis, the shear wave acoustical energy flow directions can have a swing of more than 70° [from the (110) axis] by changing the wave‐vector direction only 3° from the (110) axis. Using a grating to diffract a shear wave propagation direction around the (110) axis, we have observed the wide‐angle acoustic‐beam steering effect by a laser probe.