Gas purification by adsorption of hydrogen sulfide

• US 8,197,580 B2
• Filed: 03/08/2011
• Issued: 06/12/2012
• Est. Priority Date: 07/17/2008
• Status: Active Grant

• Current Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Hufton, Jeffrey Raymond, Golden, Timothy Christopher, Maliszewskyj, Robin Joyce, Weist, Edward Landis Jr., Quinn, Robert, Sorensen, Erin Marie
• Primary Examiner(s): Hill, Jr., Robert J
• Assistant Examiner(s): Jones, Christopher P
• Application Number:
  US13/042,879
• Publication Number:
  US 20110154989A1
• Time in Patent Office: 462 Days
• Field of Search: 95/96, 951/36, 951/39, 961/10, 961/21, 961/34, 961/40
• US Class Current: 96/121
• CPC Class Codes: B01D 2253/106 Silica or silicates
• CPC Class Codes: B01D 2253/112 Metals or metal compounds not provided for in B01D2253/104 or B01D2253/106
• CPC Class Codes: B01D 2253/202 Polymeric adsorbents
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2259/40056 Gases other than recycled product or process gas
• CPC Class Codes: B01D 2259/41 using plural beds of the same adsorbent in series
• CPC Class Codes: B01D 2259/4145 arranged in series
• CPC Class Codes: B01D 53/047 Pressure swing adsorption
• CPC Class Codes: B01J 20/06 comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/103 comprising silica
• CPC Class Codes: B01J 20/26 Synthetic macromolecular compounds
• CPC Class Codes: C01B 2203/0205 containing a reforming step
• CPC Class Codes: C01B 2203/0283 containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/042 Purification by adsorption on solids
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 2203/0485 the impurity being a sulfur compound
• CPC Class Codes: C01B 2203/84 Energy production
• CPC Class Codes: C01B 3/32 by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
• CPC Class Codes: C01B 3/48 : followed by reaction of water vapour with carbon monoxide
• CPC Class Codes: C01B 3/56 : by contacting with solids; Regeneration of used solids C01B3/508 takes precedence
• CPC Class Codes: Y02C 20/40 : of CO2
• CPC Class Codes: Y02P 20/151 : Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

Hydrogen sulfide is removed from a hydrogen rich gas stream using adsorbents having a low loss of carbon dioxide adsorption capacity upon sulfur loading including high purity silica gels, titania or highly cross-linked, non-chemically reactive resins. The adsorbents may be used to adsorb both carbon dioxide and hydrogen sulfide, or may be used as a guard bed upstream of a separate carbon dioxide adsorbent.

Claims

1. Apparatus for use in purifying hydrogen by removal of impurities from a hydrogen feed gas, said apparatus comprising a flow path for said feed gas containing an adsorbent for hydrogen sulfide, said flow path having a feed direction, and said adsorbent for hydrogen sulfide comprises a silica gel having an SiO₂ content of at least 99.2% and has a sulfur deposition rate of less than 0.04 wt % S per day H₂S exposure when continuously exposed to a 1% H₂S dry gas at 20°

C. for seven (7) days, and an adsorbent for carbon dioxide in said flow path downstream in said feed direction from said adsorbent for hydrogen sulfide.

2. Apparatus as claimed in claim 1, further comprising a gasifier for steam reforming of a carbon source and a water gas shift reactor for producing said hydrogen feed gas connected in said flow path and located upstream with respect to said feed direction from said adsorbent for hydrogen sulfide.

3. Apparatus as claimed in claim 2, further comprising an air separation unit (ASU) for producing separate flows of nitrogen and of oxygen respectively, said flow of oxygen being directed to said gasifier.

4. Apparatus as claimed in claim 3, further comprising a power generating combustor connected to receive hydrogen purified by said adsorbent for hydrogen sulfide and said adsorbent for carbon dioxide and further connected to receive said flow of nitrogen to act as a diluent for combustion of said purified hydrogen in said combustor.

5. Apparatus as claimed in claim 3, wherein said flow of nitrogen is connected to flow counter current to said feed direction as a regeneration gas flow through said adsorbent for hydrogen sulfide and further comprising a flow controller for selecting between feed gas flow through said adsorbent for hydrogen sulfide and regeneration gas flow therethrough.