Browsing by Author "Chew, Siao Chien"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Practical colorimetry of 3-Nitro-1,2,4-Triazol-5-One
    (Wiley, 2018-10-30) Tennant, Mat; Chew, Siao Chien; Krämer, Tobias; Mai, Nathalie; McAteer, Daniel; Pons, Jean-François
    A field ready colorimetric method of quantifying the concentration of aqueous 3‐nitro‐1,2,4‐triazol‐5‐one (NTO), several orders of magnitude below its environmental toxicity level, has been developed. The test allows for the immediate evaluation of the level of contamination in aqueous solution without the need for analytical equipment such as high pressure liquid chromatography (HPLC). The observed colours have been explained by the different NTO species present over the range of pH; these observations are supported by modelling and experimental results.
  • Thumbnail Image
    ItemOpen Access
    Practical remediation of 3-nitro-1,2,4-triazol-5-one wastewater
    (Wiley, 2017-11-30) Chew, Siao Chien; Tennant, Mat; Mai, Nathalie; McAteer, Daniel; Pons, Jean-François
    Limiting environmental impact is a top priority for the chemical industry, and manufacturing practices need to be well controlled to avoid any potential contamination. In order to reduce waste streams during the processing of 3-nitro-1,2,4-triazol-5-one (NTO), potentially evironmental hazardous at concentrations of 1 g/l, we investigated the potential remediation and recycling of water using a wide range of commercial sorption media. We studied the effect of experimental conditions, including flow rate, initial contaminant concentration and temperature. This led to the selection of Amberlyst A26 OH in a batch process and Activated Carbon in continuous flow, as the most effective sorption methods. Using high performance liquid chromatography photodiode array detection (HPLC-PDA), NTO was quantified from solutions, before and after remediation, showing a complete removal from a 10 g/l NTO solution. Our purification method therefore appears to be suitable for the remediation of NTO-contaminated wastewater.