A new cost effective composite getter for application in high-vacuum-multilayer-insulation tank. (September 2016)

• Record Type: Journal Article
• Authors: Wang, Jian; Zhan, Ying; Wei, Wei; Chen, Shujun; Wang, Rongshun
• Is Part Of: Vacuum. Volume 131(2016)
• Page Start: 44
• Page End: 50
• Publication Date: 2016-09
• Subjects: Hydrogen getter -- Chemisorption -- Adsorption characteristics -- Vacuum tank; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2016.05.025
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: 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 H2 O (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. Highlights: 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 H2 O (g).