| With the increasingly dilution of petroleum resources, crude oil and coal composition becomes more complicated, levels of arsenic of some of the crude oil and coal production has increased. The arsenic of the petroleum hydrocarbons will seriously affect oil and coal processing, mainly for arsenic poisoning to catalysts.Many of the catalyst used in industry are very sensitive to arsenic, hundreds of ppb even a few of ppb of arsenic can make the catalyst deactivation poisoning, and the higher concentration of arsenic, inactivation faster. And this kind of wastewater with arsenic will pollute water and soil and coal seriously, it will enter the human body through food chain or the surface water of groundwater effectively and it has great social, economic and environmental meanings to study and develop high—efficient and economy arsenic treatment technology, recycling arsenic in wastewater.Using Na2S, FeSO4 and Fe2(SO4)3 as the precipitant removals the arsenic compound in spent liquor, examine the influence of pH, reaction time and reaction temperature on the effect of arsenic removal.Results show that, the Na2S precipitation reaction has the best effect:pH at 6, reaction time for 20 min, temperature in 40℃, the rate of S/As for 6, the maximum rate of arsenic removal is 92% and the content of As reduces to 80ppb.The pH at 9, reaction time for 300 min, temperature in 40℃, the rate of Fe/As for 3, the FeSO4 precipitation reaction has the maximum rate of arsenic removal about 80% and the content of As reduces to 200ppb.These two kinds of precipitation do not need oxidation treatment before the reaction. But it is different from the As(Ⅲ) to removal the As(V) by Fe2(SO4)3. So it needs oxidation treatment.The Fe2(SO4)3 precipitation reaction has the best effect:pH at 10, reaction time for 1500 min, temperature in 20℃, the rate of Fe/As for 4, the FeSO4 precipitation reaction has the maximum rate of arsenic removal about 90% and the content of As reduces to 100ppb.
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