Sulfur durability

Takahashi, N., Suda, K.A., Hashisuka, I. et al. (2007) Sulfur durability of NO, storage and reduction catalyst with supports of Ti02, Zr02 and Zr02-Ti02 mixed oxides, Appl. Catal. B 72, 187. 

Rhenium may be electroplated from solutions of ReO in sulfuric acid. To obtain a durable rhenium plate it is desirable to deposit the metal in thin layers, annealing at high temperature after each layer is appHed. 

The composition of this alloy (54% nickel, 15% molybdenum, 15% chromium, 5% tungsten and 5% iron) is less susceptible to intergranular corrosion at welds. The presence of chromium in this alloy gives it better resistance to oxidizing conditions than the nickel/molybdenum alloy, particularly for durability in wet chlorine and concentrated hypochlorite solutions, and has many applications in chlorination processes. In cases in which hydrochloric and sulfuric acid solutions contain oxidizing agents such as ferric and cupric ions, it is better to use the nickel/molybdenum/ chromium alloy than the nickel/molybdenum alloy. 

Silicon used for diffusion treatment of carbon steels enhances corrosion resistance to sulfuric acid. Such a treatment has the surface durability of iron/silicon alloys without their marked brittleness. 

Let us note finally, that tellurium has been considered as an appropriate component for the lead grid alloy in lead-acid batteries, as improving its durability, mechanical strength, and anti-corrosive ability. In investigating Pb-Te binary alloys with different contents of Te (0.01-1.0 wt%) in sulfuric acid solution it was shown recently [104] that the introduction of Te can inhibit the growth of Pb02 and increase corrosion resistance of the positive grid alloy of a lead-acid battery. By the... 

We showed (7) earlier that copolymers of higher a-olefins, particularly 1-hexene, with 5-methyl-1,4-hexadiene can be sulfur-cured readily and that they contain unsaturation approximating the level of the methylhexadiene charged. In view of this and the excellent durability (8) during flexing exhibited by vulcanizates of such copolymers, we were interested in determining the copolymer structure and the reactivity ratios of 1-hexene and 5-methyl-l,4-hexadiene during copolymerization. 

The use of carbon-based catalysts offers certain advantages over metal catalysts due to their availability, durability, and low cost. In contrast to the metal-based catalysts, carbon catalysts are sulfur resistant and can withstand much higher temperatures. Muradov [98,99] screened a variety of carbon materials and demonstrated that the efficient catalytic methane decomposition can be accomplished over high surface area carbons at temperatures... 

Improved gasifier designs would be more durable and capable of handling a variety of carbon-based feedstocks. Advanced gas cleaning technologies would capture virtually all of the ash particles, sulfur, nitrogen, alkali, chlorine and hazardous air pollutants. 

In other words, he wanted to make it useful. He poked and prodded and experimented, adding drying agents, such as magnesium and lime. With another man, Nathaniel Hayward, he figured out how to make rubber more durable by adding sulfur, but it still melted in the heat. 

Durability of catalyst performance under the harsh environment of a GT combustor is another key issue in the development of the technology. In addition to thermomechanical issues discussed in the previous section, volatility and sintering of the active catalytic species are major concerns in this respect. On the other hand, poisoning by sulfur and other contaminants has been recognized to have a minor effect on the catalyst performance due to the high temperature of this application [8]. 

Sulfur Impregnation (14). Stronger and more durable products such as Portland cement concrete, ceramic tile and even wood and paper products have been shown to be feasible. In addition, sulfur as an impregnant for fabric liner systems would have application in ponds, holding tanks, etc. 

Sulfur Coatings (1J>, 18). Molten sulfur, often mixed with fibers or modifiers can be used to spray coatings on unbonded block or brick buildings, linings for ponds, portland cement concrete, and other applications where a durable coating is required or useful. 

The improved performance of SC over PCC is of importance not only in the applications such as corrosive industrial situations, but also in certain regular construction applications. In some areas of the world, the mineral aggregates available locally do not produce a PCC capable of withstanding the climate conditions. However, those aggregates may be used in SC to give durable building materials. Examples of this aspect of the use of sulfur concretes are sulfur concrete block projects developed by Ortega... 

The inherent flammability and low melting point of sulfur impose some limitations of SC use. Flammability can be controlled to some extent by the use of additives, and it is fortunate that the DCPD types of additives used to improve the durability of SC also impart a degree of fire resistance. Sulfur concretes are in any case considerably less of a fire hazard than wood. Because of the low thermal conductivity, heat penetration is slow, and SC can survive short exposures to fire without serious damage. Sulfur concretes do not support combustion, and flame spread is essentially zero. 

SUDICRETE (4 L). All sulfur concrete technologies involve an additive or modifier to increase durability by reducing the pro-... 

Often, the material specifications for products have been established not on the needs for the product but on what the state-of-the-art technology is capable of producing. When this happens, a particular technology is actually being prescribed. What some companies have found is that they need to revisit the needs of the product to determine whether, for example, the sulfur content they have specified is too restrictive. Some companies have found that the product requirements can be adjusted without sacrificing the utility or the durability of the product. 

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