Mercury and its compounds are highly toxic substances fo r humans. It occurs naturally and exists in various forms: elemental (or metallic); inorganic (e.g. mercuric chloride); and organic (e.g., methyl- and ethylmercury). These forms all have different toxicities and implications for health. Among naturally occurring mercury compounds, methylme rcury exerts a significant influence (neurotoxic action) on human health.
Determination of mercury in oil and petroleum hydrocarbon is currently a vital probl em due to the fact that the regulations for the mercury content in emission s from thermal power plants are becoming ever more stringent, and mercury poisons catalysts used in oil re fining.
Direct atomic absorption mercury determination (without any pre-treatment procedures) in food is complicated by its organics matrix. That is the reason why almost all AAS methods of mercury determination in foodstuff include sample digestion by acids.
The mercury concentration in crude oil and petroleum products can vary in a wide range of less than 0.1 ppb to dozens ppm. Direct mercury determination in crude oil and petroleum products at the range above 5 ppb is covered by ASTM D7622-10(2015) "Standard test method for total mercury in crude oil using combustion and direct cold vapor atomic absorption method with Zeeman background correction". Mercury determination in naphtha and light petroleum products (condensate, gasoline and diesel fuel) at a...
A conventional standard method of total mercury determination in water using atomic absorption spectrometry (AAS) involves preliminary sample digestion that takes from 30 minutes to 8 hours depending on the digestion conditions.
The use of a mercury analyzer RA-915M/RA-915+ with Zeeman background correction in combination with PYRO-915+ pyrolysis attachment provides direct determination of mercury in process and waste waters contaminated with mercury without digestion or any other sample preparation stages.
This analytical procedure is intended for measuring the content of the elements (cadmium, lead, arsenic, tin, chromium and mercury) in the samples of food products by atomic absorption spectrometry with electrothermal atomization using an “MGA-915M” Graphite Furnace AA Spectrometer.
The method is based on measuring resonance radiation absorption that occurs when the radiation passes through a layer of atomic vapor in the electrically heated graphite furnace of the “MGA-915M” AA spectrometer....