Manganese sulfide

Acanthite, see Silver sulfide Alabandite, see Manganese sulfide Alamosite, see Lead(II) silicate(2—)... 

Hoerde Also called Massener, and Hilgenstock. A process for removing sulfur from molten iron or steel by adding manganese. This produces manganese sulfide, which forms an upper phase that can be skimmed off. Invented in 1891. 

Yu and Bailey (1992) studied the reaction of nitrobenzene with four sulfide minerals under anaerobic conditions. Observed half-lives of nitrobenzene were 7.5, 40, 105, and 360 h for the reaction with sodium sulfide, alabandite (manganese sulfide), sphalerite (zinc sulfide), and molybdenite (molybdenum sulfide), respectively. Aniline and elemental sulfur were found as reduction products of nitrobenzene-manganese sulfide reaction. Aniline was also a reduction product in the nitrobenzene-molybdenum sulfide and nitrobenzene-sodium sulfide reactions. Several unidentified products formed in the reaction of nitrobenzene and sphalerite (Yu and Bailey, 1992). 

Figure 5. Elongated manganese sulfide inclusion in aluminum killed steel after hot...

What happened The German and Japanese steel metallurgists had understood much earlier in the game, during the sixties, the paramount importance of eliminating the manganese sulfide inclusions. Their equipment and highly quality-oriented minds allowed them to tackle the difficult orders ahead of everybody else. 

SET UP APPARATUS FOR MAKING HYDROGEN SULFIDE [SEE PAGE 53). POUR SOLUTION OF MnClj INTO TEST TUBE. DILUTE IT IF NECESSARY. LEAD H,S INTO IT. YOU GET MANGANESE SULFIDE. 

ALABANDITE. Manganese sulfide. MnS. Associated with pyrite, sphalerite. and galena in metallic sulfide vein deposits. 

Among the interesting results of such endeavors for 304 stainless steel is a stress upon inclusions involving manganese sulfide and manganese oxide. Surprisingly, traces ofCu in the steel are detected and form flowerlike deposits prior to the initiation of a pit. Metallic inclusions tend to dissolve anodically in 0.1 MNaCl at 400 mV SCE. There is some evidence for their readsorption. However, to be the cause ofpit initiation, the inclusions have to be at least 0.7 jum in size. It may be that the local current density for dissolution at smaller inclusions is too high to sustain CF adsorption there. 

Figure 2.25 SEM view of the fracture surface of a low-carbon steel specimen broken in tension, showing ductile dimples, local quasicleavage, and manganese sulfide inclusions. (Reprinted with permission from ASM International. All rights reserved www.asminternational.org)...

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