Using silver nano particles for sampling of toxic mercury vapors from industrial air sample

Mercury is one of the toxic metals that damages the nervous system and kidneys. Therefore, monitoring of mercury vapors in the environments is essential. A new adsorbent was made from silver nanoparticles on a bed of quartz. The nano-adsorbent was capable for sampling of the trace amounts of mercury vapor from air. In this study, the required mercury vapor was generate by hydride generation atomic absorption spectrometry and the necessary analysis was performed by cold vapor atomic absorption spectrometry. Mercury vapors in the Stationary phase, were concentrated as much as 2300 times (Atomic absorption detection limit was 1.15 microgram per liter of air). Thus by this stationary phase, the trace amounts of mercury vapors can be detected up to 0.5 nano gram per liter of air. The detected value of the presented method is 200 times lower than the occupational safety and health administration (OSHA) standards for mercury vapors. Heater accessory at the temperature of 245 °C was used for thermal desorption of mercury from nano silver adsorbent. Optimal time of desorption was obtained 150 seconds and the Repeatability of the method was 58 times. The mercury vapors absorbed on nano silver adsorbent could be maintained at 80 days at the room temperature (25 °C). The presented adsorbent is very useful for sampling of the trace amounts of mercury vapors from air. Moreover, it can be regenerated easily is suitable or sampling at 25 to 70 °C. Due to oxidation of silver and reduction in uptake of nanoparticles, oven temperature of 245 °C is used for the recovery of metallic silver. Low amount of adsorbent, high absorbency, high repeatability for sampling, low cost and high accuracy are of the advantages of the presented method.