UIO-66-NH2 Packed Needle Trap for Accurate and Reliable Sampling and Analysis of the Halogenated Volatile Organic Compounds in Air

Abstract

ABSTRACT This paper introduces a novel inside needle adsorption trap device based on UiO-66-NH2 adsorbent for the sampling and analysis of halogenated volatile organic compounds (HVOCs), including chloroform, carbon tetrachloride, and perchloroethylene in air. In this study, the UiO-66-NH2 adsorbent was first synthesized and then packed into spinal needles (22 Gauge). This study was conducted both in the laboratory and in the field. Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD) were used to investigate the sorbent characteristics. In this study, Response Surface Methodology (RSM) and Central Composite Design (CCD) were utilized to optimize the effects of sampling parameters and desorption parameters on needle trap device (NTD) performance. In this regard, a constant concentration of the compounds of interest was injected into a standard chamber, and then the packed NTD was used for the sampling of HVOCs under a given condition. According to the results, the maximum peak area response was obtained at 280 ˚C of desorption temperature and 4 min of desorption time. The results showed that increased sampling humidity and temperature interfered with the NTD performance and decreased the peak area responses of the analytes. The proposed NTD had a high sensitivity for the sampling and analysis of the desired compounds. Limit of Detection (LOD) and the Limit of Quantitation (LOQ) of the NTD for the analytes were in the range 0.01-0.03 and 0.02-0.05 ng.mL-1, respectively. Moreover, the repeatability of the proposed NTD was obtained to be in the range of 2.3-9.1%. Therefore, the NTD packed with UiO-66-NH2 adsorbent can be used as a suitable and robust method for the active sampling and analysis of occupational/environmental pollutants in the air.