title: Micro gas analysis system for measurement of atmospheric hydrogen sulfide and sulfur dioxide.
abstract: A honeycomb structure microchannel scrubber was developed to achieve efficient and stable gas collection. A thin porous membrane was pasted on a microchannel by the adhesive force of a fresh polydimethylsiloxane surface. The microchannel scrubber achieved much more efficient gas collection than conventional impingers and diffusion scrubbers. Two sets of the microchannel scrubbers and detectors were integrated in a 10 cm x 9 cm plastic board to create a micro gas analysis system (microGAS) for simultaneous measurements of H2S and SO2. The whole system including a battery was incorporated in a carrying case 34 cm W x 16 cm D x 17 cm H for use in the field. Liquid flows at 30 microl min(-1) were obtained by bimetal micropumps. The estimated detection limits were 0.1 ppbv for H2S and 1 ppbv for SO2. The system was demonstrated for real atmospheric gas analysis, and the results agreed well with data concurrently obtained by ion chromatography coupled with a cylindrical diffusion scrubber. The system we developed allowed automated continuous analyses in the field and achieved a much higher time resolution compared to those by ion chromatographic analysis.
authors.affiliation: Department of Science, Kumamoto University, 2-39-1, Kurokami, Kumamoto, 860-8555, Japan.
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Ohira
authors.forename: Kei
authors.initials: K
authors.lastname: Toda
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D001272:Atmosphere / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods; D005740:Gases / Q000032:analysis / Q000737:chemistry; D006862:Hydrogen Sulfide / Q000032:analysis* / Q000737:chemistry; D008567:Membranes, Artificial; D008832:Microchemistry / Q000295:instrumentation / Q000379:methods; D044085:Microfluidics / Q000295:instrumentation* / Q000379:methods; D008904:Miniaturization; D013458:Sulfur Dioxide / Q000032:analysis / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D005740:Gases; D008567:Membranes, Artificial; D013458:Sulfur Dioxide; D006862:Hydrogen Sulfide