Portable Trap–Sensor System for Monitoring Low Levels of Ethylene

Abstract

A portable device for measuring trace amounts of ethylene is described. Ethylene was trapped on a silver catalyst, which was then flash heated, releasing a plug of ethylene into a flowing gas stream. The ethylene was detected using an amperometric sensor with a gold-Nafion sensing electrode. For a trap time of 10 min, a detection limit of 1 ppb of ethylene was achieved. This compares with 40 ppb obtained using the sensor without pretrapping. In addition to the improvement in sensitivity, the trapping procedure also allowed improved selectivity, making the device suitable for applications where very low levels of ethylene need to be measured and interferents may be present.

Selective Detection of Ethylene Gas Using Carbon Nanotube‐based Devices: Utility in Determination of Fruit Ripeness

“…Traditionally, ethylene concentrations are monitored through gas chromatography5a or laser acoustic spectroscopy,5b which both require expensive instrumentation and are not suitable for in‐field measurements. Other techniques suggested are based on amperometric5c or electrochemical5d methods or rely on changes in luminescence properties 5e. 6 Furthermore, gas‐sampling tubes based on a colorimetric reaction are available 1.…”

Selektiver Nachweis von Ethylengas mit Kohlenstoffnanoröhren als Hilfsmittel in der Fruchtreifebestimmung

“…Herkömmliche Methoden sind die Gaschromatographie5a oder laserakustische Spektroskopie,5b beide benötigen jedoch kostspielige Instrumente und sind ungeeignet für praktische Anwendungen. Darüber hinaus wurden verschiedene Methoden vorgeschlagen, die auf amperometrischen5c oder elektrochemischen5d Techniken beruhen oder auf Änderungen in den Lumineszenzeigenschaften 5e. 6 Zusätzlich stehen Gas‐Teströhrchen zur Verfügung, denen eine kolorimetrische Reaktion zugrunde liegt 1.…”

Detection of Ethylene Gas by Fluorescence Turn‐On of a Conjugated Polymer

“…Both techniques suffer from the disadvantage of being operationally impractical and do not allow for real‐time measurements. Other sensing systems that have been suggested use electrochemical2c or chemoresistive methods,2d magnetoelastic sensing,2e and photoluminescence quenching 2f. However, all of these systems have drawbacks such as high cost, impracticability, or insufficient sensitivity towards ethylene.…”