Determination of Arsenic in Petroleum Fractions and Reforming Catalysts

Arsenic determination in naphtha by electrothermal atomic absorption spectrometry after preconcentration using multiple injections

“…Typical arsenic concentration in naphtha ranges from v1 to 40 mg L 21 . 2,[6][7][8][9][10][11][12][13] In 1959, Powers et al suggested arsenic would be present in naphtha as alkyl arsines. 2 Studies conducted by Puri and Irgolic in 1989 revealed that trimethylated and monomethylated arsenic are, in fact, the predominant arsenic species in petroleum products.…”

“…7 In the following years, other authors proposed different methodologies based on spectrophotometric determinations of arsenic as molybdenum blue or silver diethyldithiocarbamate complexes. 2,6,8,9 Those methods all have in common the laborious and time-consuming sample pretreatment step for matrix separation or analyte preconcentration, such as wet acid digestion, combustion, liquid-liquid extraction, distillation and arsine generation.…”

Feed Additives, Metabolism of Two Forms of Dietary Arsenic by the Rat

“…There w'ere several attractive hypotheses to explain this enigma. Ehrlich (2) believed there must be reduction to the arsenoxide to account for the delayed 1 Present address: Department of Microbiology, University of Illinois, Urbana,111. in vivo activity. Others suggested the possibility of a slow release of inorganic arsenic.…”

Nondestructive Activation Analysis of Crude Oils for Arsenic to One Part per Billion and the Simultaneous Determination of Five Other Trace Elements.

“…All of the existing wet chemical methods for the analysis of arsenic in hydrogen media at less than 100 p.p.b. depend upon the destruction of the hydrocarbon and conversion of the arsenic to ionic form (1,12,16). This process is undesirable because arsenic may be lost at the elevated temperatures generally used for ashing the sample (16), because a relatively high arsenic blank results from the reagents in ashing the volume of oils required for suitable sensitivity, and, finally, because the ashing of petroleum under conditions to reduce loss of trace elements is tedious and time-consuming.…”