Facile Regeneration vitreous microfibrous entrapped supported ZnO sorbent with high contacting efficiency for bulk H ₂S removal from reformate streams in fuel cell applications

In this study, a microfibrous carrier consisting of 3vol% of 8 □m (dia.) glass fibers is utilized to entrap 45 vol% of 150-250 □m (dia.) SiO ₂ support particulates. ZnO is then nano-dispersed onto the support by impregnation at the loading of 17 wt%. At equivalent bed volumes, ZnO/SiO ₂ entrapped materials provide 2-fold longer breakthrough times for H ₂S (with a 67% reduction in sorbent loading) compared to packed beds of 1-2 mm commercial extradates. 5-log reductions in H ₂S concentration with up to 75% ZnO utilization at breakthrough are achieved. H ₂S concentrations from 60 to 2,000 ppmv can be reduced to as little as 0.6 ppmv at 400°C in 30% H ₂O at a face velocity of 1.7cm/s for layers as thin as 1.0 mm. At 500-600°C, ZnO/SiO ₂ entrapped materials provide much higher regenerability in air than 1-2mm commercial extrudates do. The use of glass fibers permits greater than 50 regeneration cycles. Glass Fiber, Sorbent, H ₂S removal, Fuel Cell.