Citric acid sulfides

Inorganic heavy metals are usually removed from aqueous waste streams by chemical precipitation in various forms (carbonates, hydroxides, sulfide) at different pH values. The solubiUty curves for various metal hydroxides, when they are present alone, are shown in Figure 7. The presence of other metals and complexing agents (ammonia, citric acid, EDTA, etc) strongly affects these solubiUty curves and requires careful evaluation to determine the residual concentration values after treatment (see Table 9) (38,39). 

Citric acid is used to chelate vanadium catalyst in a process for removing hydrogen sulfide from natural and refinery gas and forming elemental sulfur, a valuable product (133). 

Complexes of tetravalent zirconium with organic acids, such as citric, tartaric, malic, and lactic acids, and a complex of aluminum and citric acid have been claimed to be active as dispersants. The dispersant is especially useful in dispersing bentonite suspensions [288]. Polymers with amine sulfide terminal moieties are synthesized by using aminethiols as chain transfer agents in aqueous addition polymerizations. The polymers are useful as mineral dispersants [1182]. 

Citric acid 10 to saturated s Hydrogen sulfide gas Unknown s... 

The activity of chlorine as a bactericide is decreased by the presence of large quantities of algal slimes and certain process leaks (for example, hydrogen sulfide from petrochemical industries, ammonium compounds from fertilizer production, or citrates from the bioengineering manufacture of citric acid, but not hydrocarbon oil leaks from an oil refinery). 

PROP Consists of a 2.4% w/v selenium sulfide in aq suspension, also contains bentonite, sodium alkyl aryl sulfonate, sodium phosphate, glycerol monoricinoleate, citric acid, captan, and perfume (FEREAC 41,7218,76). 

Urine can turn dark in color in the first 24 hours after parenteral iron injection. The reddish-brown color, which has been observed after the intramuscular injection of iron sorbitol-citric acid complex (SED-8, 515), is due to urinary excretion of part of the iron compound. It has to be distinguished from the black discoloration that may develop if urine of patients who have received iron-sorbitex is allowed to stand, assumed to be due to production of iron sulfide by bacterial growth. Phenomena of this kind are unhkely to occur after the... 

Citric acid is incompatible with potassium tartrate, alkali and alkaline earth carbonates and bicarbonates, acetates, and sulfides. Incompatibilities also include oxidizing agents, bases, reducing agents, and nitrates. It is potentially explosive in combination with metal nitrates. On storage, sucrose may crystallize from syrups in the presence of citric acid. 

Regeneration of the uncomplexed citric acid at the same time as formation of an elemental sulfur product from the bisulfite anion is obtained by treating the absorption solution with hydrogen sulfide [41] (Eq. 3.30). 

The U.S. Bureau of Mines has tested a pilot-scale sulfur dioxide to sulfur conversion process which involves initial absorption of sulfur dioxide in an aqueous solution of citric acid, H0C(CH2C02H)2C02H, and sodium citrate (Fig. 13.11). This solution is then contacted with hydrogen sulfide to reduce the sulfur dioxide to elemental sulfur, which is then readily filtered from the resulting slurry (Eqs. 13.41-13.43). 

S)- (113162-02-0), 70, 47 (E)-Clnnamaldehyde, 70, 197, 240 Citric acid, 70, 54 CONJUGATED ENYNES, 70, 215 Copper(l) bromide-dimethyl sulfide complex, 70, 218 Copper cyanide (544-92-3), 70, 196 Copper(l) thiophenoxide, 70, 206 Copper-zinc organometallic, 70, 196 Crown ethers, chiral, 70, 65... 

U.S. 5302323 (1994) Hartung et al. (Abbott Lab.) 0.5-2.5% selenium sulfide two suspending agents di(hydrogenated) tallow phthalic acid amide and one selected from hydroxypropylbmethylcellulose and Mg Al silicate pH 4.0-6.5 buffer system with Na citrate and citric acid at least 18% anionic surfactant Improved pH stability, suspension stability, lathering, and conditioning (three-in-one)... 

Furukawa Y, Inubushi K (2002) Feasible suppression technique of methane emission from paddy soil by iron amendment. Nutr Cycl Agroecosyst 64 193-201 Fuseler K, Krekeler D, Sydow U, Cypionka H (1996) A common pathway of sulfide oxidation by sulfate-reducing bacteria. FEMS Microbiol Lett 144 129-134 Galushko AS, Schink B (2000) Oxidation of acetate through reactions of the citric acid cycle by Geobacter sulfurreducens in pure culture and in syntrophic coculture. Arch Microbiol 174 314-321... 

Complex I, also referred to as the NADH dehydrogenase complex, catalyzes the transfer of electrons from NADH to UQ. The major sources of NADH include several reactions of the citric acid cycle (see pp. 284-287), and fatty acid oxidation (Chapter 12). Composed of at least 25 different polypeptides, complex I is the largest protein component in the inner membrane. In addition to one molecule of FMN, the complex contains seven iron-sulfur centers (Figure 10.2). Iron-sulfur centers, which may consist of two or four iron atoms complexed with an equal number of sulfide ions, mediate 1-electron transfer reactions. Proteins that contain iron-sulfur centers are often referred to as nonheme iron proteins. Although the structure and function of complex I are still poorly understood, it is believed that NADH reduces FMN to FMNH2. Electrons are then transferred from FMNH2 to an iron-sulfur center, 1 electron at a time. After transfer from one iron-sulfur center to another, the electrons are eventually donated to UQ (Figure 10.3). 

A 0.25% citric acid soaking solution improved the color of canned lima beans. Acidified soak water improves color by retarding the retention of Fe and Cu salts with sulfides or polyphenols that contribute to discoloration (13). 

LEAD DINITRATE (10099-74-8) Pb(N03)2 Noncombustible solid. A strong oxidizer accelerates burning of combustible materials. Violent reaction, or may form explosive materials, with reducing agents, including hydrides, nitrides, phosphoms, stannous chloride, and sulfides alkyl esters (forms explosive alkyl nitrates) combustible materials, potassium hexanitrocobalite(III) (C. I. pigment yellow), cyclopentadienyl sodium, red hot carbon, lead(II) phosphinate, phosphoms, tin(II) chloride. Incompatible with aluminum, ammonia, ammonium thiocyanate (mixture forms the shock- and friction sensitive explosive guanidine nitrate) citric acid, hydrozoic acid, metal phosphinates, methyl isocyanoacetate, sodium peroxyborate, potassium acetate. 

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