Combined Claus reaction

Standard processing combines sorption in alkaline solution, regeneration of the solvent with concurrent release of high-concentration H2S, and finally conversion of the H2S to elemental sulfur through the Claus reaction scheme ... 

Sulfur dioxide, SO2, adsorbed on zeohtes was first investigated by Deo et al. [646] and Foerster and Seelemann [649]. Deo et al. used as adsorbents Na-Y and H-Y zeolites, and their investigations were related to the modified Claus reaction which occurs according to the overall reaction formula of Eq. (29). Also, studies by Karge et al. [227,228], using combined IR and UV-Vis spectroscopy for measurements of SO2 adsorption on faujasite-type zeolites, were related to the modified Claus reaction ... 

Claus Sulfur Recovery Process, At the sulfur plant, H2S is combined with sour-water stripper off-gas and sent to a Claus unit. Invented in 1881 by Carl Freidrich Claus/ almost every refinery in the world uses some version of this process to convert H2S into elemental sulfur. A simplified version of Claus-reaction chemistry is shown in Figure 26. 

In the application illustrated, acid gas containing about 17% hydrogen sulfide is fed to a combination direct oxidation/Claus system which produces elemental sulfur and an exhaust stream containing 1.7% hydrogen sulfide. In the sulfur plant, a portion of the hydrogen sulfide is oxidized directly to sulfur, while another portion reacts with recycled sulfur dioxide by the conventional Claus reaction. The amount of oxidizing gas fed to the sulfur plant is controlled to assure that sulfur in the tail gas is in the form of hydrogen sulfide, not sulfur dioxide. 

Figure 1 illustrates the practical combinations of known processes. With low CO2 acid gas, and only methane as impurity, the conventional Claus process may be used if the reaction furnace is designed to assure complete conversion of hydrocarbons to simple compounds such as COS and H2S. 

Tannio acid seems to form combinations with solutions of sterch, giving a greyish-white flaky precipitate, which becomes transparent in the heat, but reappears in the usual form as the liquid cools. This acid decolors the blue iodide of starch, and when present in sufficient quantity it prevents the entire decomposition of focula by means of diastase. The reaction contributes in part to the formation of artificial leather on Claus-SBN s principle, as already detailed in this work. 

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