Desulfurization novel

Thermolysis of trithiane (69) or carbonate (70) at reduced pressure yields methylene-thiirane which is stable in cold, dilute solution (Scheme 152) (78JA7436, 78RTC214). A novel acenaphthylene episulfide is obtained by treatment of the six-membered sulfoxide (71) with acetic anhydride (Scheme 153) (68JA1676), and photolysis of (72) gives a low yield of episulfide (73 Scheme 154) (72JA521). Low yields may be due to the desulfurization of the thiiranes under the reaction conditions. 

Hydrogen Hydrogen recovery was the first large commercial membrane gas separation. Polysulfone fiber membranes became available in 1980 at a time when H9 needs were rising, and these novel membranes qiiickly came to dominate the market. Applications include recovery of H9 from ammonia purge gas, and extraction of H9 from petroleum crackiug streams. Hydrogen once diverted to low-quahty fuel use is now recovered to become ammonia, or is used to desulfurize fuel, etc. H9 is the fast gas. 

The course of the photolysis of a number of cyclic sulfoxides, however, has been shown not to involve simple photoextrusion processes. In fact, the work of Schultz and Schlessinger19,20 and Still and coworkers21 has shown the existence of a novel desulfurization pathway leading to cyclic ethers or to carbonyl compounds by formal loss of the sulfur atom only, by certain cyclic sulfoxides. 

Jang, H.-N., Son, H.-Y., Jang, J.-H., et al., A novel klebisiella oxytoca which removes sulfur from fossil fuel that contains organic sulfur compound and desulfurizing method. Patent No. KR205255. 1999, July 01. 

Nakayama, N. Matsubara, T. Ohshiro, T., et al., A Novel Enzyme, 2 -Hydroxybiphenyl-2-Sulfinate Desulfinase (DszB), From a Dibenzothiophene-Desulfurizing Bacterium Rhodococcus Erythropolis KA2-5-1 Gene Overexpression and Enzyme Characterization. Biochimica Et Biophysica Acta-Proteins and Proteomics, 2002. 1598(1-2) pp. 122-130. 

Watanabe, K. Noda, K. Ohta, Y., and Maruhashi, K., Desulfurization of hght gas oil by a novel recombinant strain from Pseudomonas aeruginosa. Biotechnology Letters, 2002. 24(11) pp. 897-903. 

A novel Klebisiella oxytoca which removes sulfur from fossil fuel that contains organic sulfur compound and desulfurizing method [132],... 

Novel example of this reaction type are given by the copper-catalyzed decomposition of ethyl diazoacetate in the presence of bis(dialkoxyphosphoryl)disulfides 374 350 where P/S insertion sometimes accompanies the S/S insertion, and of bis(dialkoxy-thiophosphoryl)trisulfides 375 351 where desulfurization to give the disulfide derived product occurs during the reaction. Only P/S insertion product was obtained from bis(dialkoxyphosphoryl)trisulfide or -tetrasulfide 376 the copper-catalyst is dispensable in this case351K... 

A novel route to synthesize l,3 -triazine-2,4(l//,3//)-diones through the desulfurization of thiocarboamides, such as 1,3-disubstituted 2-thioureas, trisubstituted thioureas and N-substituted thioamides by silver cyanate has been reported <00H(53)929>. Treatment of urazole 23 with one equivalent of sodium hydride under anhydrous conditions, followed by addition of dimethyl sulfate, leads to l,3,5-triazine-2,4-dione 24 in 80% yield . 

Ispra Mark 13A A flue-gas desulfurization process developed at the Joint Research Centre of the European Community at Ispra, Italy, from 1979. It uses a novel electrochemical method to regenerate the solution used for absorbing the sulfur dioxide. The products are concentrated sulfuric acid and hydrogen. The absorbent is a dilute aqueous solution of sulfuric and hydrobromic acids, containing a small amount of elemental bromine. Sulfur dioxide reacts with the bromine thus ... 

A novel Double Draw-Off (DDO) ciystallizer has been designed in order to improve the particle size distribution in the precipitation of CaS03 V 20 simulated Flue Gas Desulfurization (FGD) liquor. The effects of DDO ratio and residence time on the mean particle size were studied. Industrial conditions were maintained in all experiments as far as practical. Significant improvement in mean particle size was achieved. The performance of an actual industrial DDO ciystallizer (DuPont) for gypsum ciystallization was reported. 

Another novel catalyst modification has been suggested in which the active Co-Mo-S catalyst is used in combination with an acidic catalyst such as a zeolite. This combination has the potential of opening another reaction pathway by isomerization of the alkyl groups on molecules such as 4,6-DMDBT to positions that do not sterically interfere with adsorption or oxidative addition. This is illustrated in Fig. 33. Gates and co-workers reported many years ago that the 2,8- and 3,7-dimethyldibenzothiophenes are much more easily desulfurized than 4,6-DMDBT (see Table XII) (26). Therefore, a combination of an isomerization catalyst and a desulfurization catalyst could be synergistic for removing dialkylbenzothiophenes. 

Both of the above approaches employed a metal ion as a template about which the corrin cyclization was performed, but the nickel or cobalt ions could not subsequently be removed. In order to obtain metal-free corrins, a new route was therefore devised (67AG865) which employed the novel principle of sulfide contraction (Scheme 22). Thus the sodium salt of the precorrin (284) (Scheme 23) was transformed into the thiolactam (285), and loose complexation with zinc(II) ions caused cyclization to give (286), which was treated with benzoyl peroxide and acid to give the ring-expanded compound (287). Contraction with TFA/DMF gave the corrins (288) and (289), and the major of these (289) was desulfurized with triphenylphosphine and acid to give (288). Finally, demetallation with TFA gave the required metal-free corrin (290), a source for a whole variety of metal derivatives. 

The triazoline adducts from benzvalene (Scheme 21)162 and diphospha-benzvalene (Scheme 22) photolyze to yield novel tetracyclic aziridine ring systems165 that are valence isomers of azepines,162 whereas that from De-war thiophene (Scheme 20) gives a novel tricyclic aziridine that desulfurizes with triphenylphosphine to yield the trifluoromethylated Dewar pyrrole (Scheme 153).15 9,160 The stabilization of these strained molecules is attributed to the perfluoroalkyl effect.159... 

Babich, I.V. and Moulijn, J.A. (2003) Science and technology of novel processes for deep desulfurization of oil refinery streams a review. Fuel, 82, 607. 

The technical and economic aspects of wet flue gas simultaneous desulfurization and denitrification systems are presented so that their practicality for utilization by utility industry can be assessed. The emphasis is on the kinetics of the systems based on the employment of ferrous chelates to promote the solubility of NO and the reactivity of NO with SO2 in scrubbing liquors. Analytical techniques are developed for characterizing reaction intermediates and products. Alternative approaches and novel ideas that could develop into a more efficient and cost-effective scrubber system employing metal chelate additives are discussed. 

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