A new cost effective composite getter for application in high-vacuum-multilayer-insulation tank

•Sorption performances of new cheap getters using our new experimental setup.•CuO & C was suitable to adsorb H2 in high vacuum multilayer insulation tank.•Sorption isotherm of CuO & C was type I and accurately described by Langmuir model.•Saturated sorption amount of CuO & C was 296.4 mL(stp)/g at room temperature.•Sorption products of CuO & C were Cu and H2O (g).

H2 is the main residual gas in the chamber of high-vacuum-multilayer-insulation tank (HVMIT) and is adsorbed by the expensive getter PdO. Adsorption characteristics of more cost effective getters (CuO, CuO & 5A and CuO & C) were investigated and adsorption products were analyzed by measuring the pressure decrease in a known volume as function of time using our designed experimental setup. CuO & C was more suitable to adsorb H2 in HVMIT than the other getters investigated. H2 adsorption amount and pumping speed were significantly larger than CuO and CuO & 5A getter systems. Working temperature could be also reduced with respect to these two getter bed, this being advantageous from the operational point of view. Adsorption isotherm was type I as accurately described by Langmuir model. H2 sorption amount was 170.6 mL(stp)/g at equilibrium pressure not higher than 5.8 × 10−2 Pa, saturated sorption amount was 296.4 mL(stp)/g at room temperature, and sorption products were Cu and H2O (g). When adsorption equilibrium was obtained, HVMIT was fed with liquid nitrogen. Interlayer pressure decreased sharply to 5.83 × 10−4 Pa in a stepwise shape for 10 h. This vacuum level is appropriate for ensuring good insulation level in the tank.