Ionic Liquid Gas Sensors for Detection of Flammable Gases in Workplace

Details

• Personal Author:
  Zeng X
• Description:
  Sensors for flammable gas detection are essential in occupational health and safety to prevent fire or explosion in gas facilities and underground mining. Among the flammable gas analytes, methane is one of the most important to detect. Methane is the major constituent of natural gas that is one of the most abundant US energy resources. Its use is being expanded to meet the rising energy needs in industry, homes, and truck transportation over the next decade. Methane is also the constituent of landfill and mine gases that is likely to pose the greatest explosion hazard. Except for reactions with chlorine or oxygen, methane is mostly chemically inert and is odorless and colorless. Moreover, the physical adsorption of methane on solid materials is typically very weak and as a result, methane is typically detected by heated catalytic bead [pellister], heated metal oxides [HMOx], or non-dispersive infrared instruments [NDIR], each having its own limitations. Additionally, the cost and the power required for many methane sensors precludes them from widespread deployment in mines, industrial installments, fence-lines or pipelines, homes, or wherever methane/natural gas is used. Over a three year period of time, we investigated the Ionic Liquids (ILs) as new sensing materials for new methane sensors using real-time, portable, low cost orthogonal Electrochemical (EC) and Quartz Crystal Microbalance (QCM) transducers for readout. Having negligible vapor pressure at ambient conditions, high thermal stability in air, and high conductivity, ILs are well suited for use as coatings in QCM based methane sensor development and as electrolytes in Electrochemical based methane sensor development. Specific Aims of this study were: 1. Develop, Characterize and Optimize Ionic Liquid Chemical Interface Immobilization to Form Robust, Thin Rigid Film. 2. Evaluate and Validate the IL Sensor Array for Methane Detection. 3. Develop IL Electrochemical Sensors for Methane Detection. 4. Refine the Sensor to Increase Stability; Heighten Sensitivity and Selectivity for Real World Applications. Our studies involve basic research of methane adsorptions in a variety of IL coatings for QCM based methane sensor development as well as the basic research of methane electrochemical oxidation in various ILs for electrochemical methane sensor development. Our studies also involve the characterization of the methane EC and QCM sensors at real world conditions (water interferences and at various temperatures). We have completed the investigation of the task specific ILs and their surface immobilization on solid supports as a replacement of conventional recognition elements for QCM methane sensors. We have revealed two new mechanisms of methane electrochemical oxidation in ILs at anaerobic and aerobic conditions. The feasibility of integrated EC and QCM methane sensors to detect methane at real world conditions has also been investigated. The knowledge gained from these investigations prove that the self-organized phases with aggregated non-polar and charged domains of ILs are the choice of sensing materials for EC and QCM based methane sensors which form the foundation to develop commercial methane sensors for mine safety application using the results obtained from this study. [Description provided by NIOSH]
• Subjects:
  Mining Occupational Health Safety
• Keywords:
  Electrochemical Analysis Explosive Gases Flammable Gases Gas Detectors Natural Gas Sensors Underground Mining
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Final Grant Report
• Place as Subject:
  Michigan ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-15
• NIOSHTIC Number:
  nn:20059164
• NTIS Accession Number:
  PB2021-100108
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R21-OH-009099, 2012 Oct; :1-15
• Contact Point Address:
  Xiangqun Zeng, Chemistry Department, SEB 231, Oakland University, Rochester, MI 48309
• Email:
  zeng@oakland.edu
• CAS Registry Number:
  Methane (CAS RN 74-82-8)
• Federal Fiscal Year:
  2013
• NORA Priority Area:
  Mining
• Performing Organization:
  Oakland University, Rochester, Michigan
• Peer Reviewed:
  False
• Start Date:
  20090801
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20120731
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:80f4f1f2a2feab8c218242144050071612c197eee777f3450cf238d6bb1a85d99e33de3fbb39c9a7341ae3e39aa33e405030e79868583c42fc211a723d21a2e9
• Download URL:
  https://stacks.cdc.gov/view/cdc/218969/cdc_218969_DS1.pdf
• File Type:
  [PDF - 1.92 MB ]