Iron sulfides formation

Shipment nd Stora.ge, Sulfur monochloride is minimally corrosive to carbon steel and iron when dry. If it is necessary to avoid discoloration caused by iron sulfide formation or chloride stress cracking, 310 stainless steel should be used. Sulfur monochloride is shipped in tank cars, tank tmcks, and steel dmms. When wet, it behaves like hydrochloric acid and attacks steel, cast iron, aluminum, stainless steels, copper and copper alloys, and many nickel-based materials. Alloys of 62 Ni—28 Mo and 54 Ni—15 Cr—16 Mo are useful under these conditions. Under DOT HM-181 sulfur monochloride is classified as a Poison Inhalation Hazard (PIH) Zone B, as well as a Corrosive Material (DOT Hazard Class B). Shipment information is available (140). 

Major problems in oil and gas operations result from the biogenic formation of hydrogen sulfide (H2S) in the reservoir. The presence of H2S results in increased corrosion, iron sulfide formation, higher operating costs, and reduced revenue and constitutes a serious environmental and health hazard. 

Frankenberger Jr. WT, Engberg RA (eds), Marcel Dekker, New York, p 281-296 Lyons TW (1997) Sulfur isotopic trends and pathways of iron sulfide formation in upper Holocene sediments of the anoxic Black Sea. Geochim Cosmochim Acta 61(16) 3367-3382... 

Petrographic work is difficult to correlate with bulk chemical analyses due to the sporadic distribution of pyrite. However, petrographic observations offer clues revealing processes involved in iron sulfide formation. 

Tribochemical reactions of dibenzyl disulfide in the presence of a second additive (e.g., ZDDP, chlorinated paraffin, amines, phenol, barium alkylbenzylsulfonate, and polyisobutenylsuccinimide) were investigated (Plaza, 1989). All the systems tested reduced the concentration of elemental sulfur in the oil to low loads. Formation of FeS was reduced in the presence of chlorinated paraffin, barium alkylbenzylsulfonate, ZDDP, and polyisobutenylsuccinimide. The amines and hindered phenol had little or no effect on iron sulfide formation at higher loads. 

Roden, E.E., and Edmonds, J.W. (1997) Phosphate mobilization in iron-rich anaerobic sediments microbial Fe(III) oxide reduction versus iron-sulfide formation. Arch. Hydrobiol. 139, 347-378. 

The sulfur budget for the Black Sea has been considered in several papers [23, 24,74-77]. Sulfide sources are sulfide production in sediments, sulfide flux at the sediment/water interface, and sulfide production in the water column. Sulfide sinks are sulfide oxidation at the oxic/anoxic interface and in the basin interior by dissolved oxygen of the modified Mediterranean water and iron sulfide formation in the water column. 

Rickard D.T., The chemistry of iron sulfides formation at low temperatures. Stockholm Contrib. Geol. 20, 67-95 [1969]. 

At this point construction of e model is complete except for incorporation of Ir into the system of equations. As discussed above,is an important variable in the kinetics of iron sulfide formation. 

However because the rate law expressions for iron sulfide formation (equations 8 and lO) are non-linear the differential equations for H2S and the iron sulfides are not amenable to explicit solution Thus it is important to develop an equation for that can be incorporated in a numerical solution technique such as that of Runge-Kutta (15) Fortunately an appiropriate differential equation for can be developed firom charge balance considerations Here it is assumed that dissolved substances other than those listed in Table I are not affected by diagenesis If this is true, then a charge balance difference equation can be written (16) ... 

The carbon constraint on iron sulfide formation is ased on reaction 5 and Berner s (12) demonstration... 

Lin S., Huang K.-M. and Chen S.-K. (2000) Organic carbon deposition and its control on iron sulfide formation of the southern East China Sea continental shelf sediments. Cont. Shelf Res. 20, 619-635. 

Caustic addition to neutralize heat-stable salts to mitigate corrosion and thereby reduce iron sulfide formation (Bacon, 1987). 

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