Sulfides metal-ammonia

Chromic(VI) acid Acetic acid, acetic anhydride, acetone, alcohols, alkali metals, ammonia, dimethylformamide, camphor, glycerol, hydrogen sulfide, phosphorus, pyridine, selenium, sulfur, turpentine, flammable liquids in general... 

Nitric acid, fuming phite, thiocyanates Organic matter, nonmetals, most metals, ammonia, chlorosulfonic acid, chromium trioxide, cyanides, dichromates, hydrazines, hydrides, HCN, HI, hydrogen sulfide, sulfur dioxide, sulfur halides, sulfuric acid, flammable liquids... 

The hydrogen sulfide and ammonia can be removed by amine extraction and acid washes respectively. Hydrotreating also removes metals from the feed that would otherwise poison the reforming and cracking catalysts. 

Two sulfide precipitation methods currently used are the soluble sulfide precipitation (SSP) and insoluble sulfide precipitation (ISP) processes. Soluble sulfides and insoluble sulfides are used to precipitate dissolved metals as metal sulfides. Metal sulfides have lower solubilities than the hydroxides, resulting in lower residual metal concentrations in the treated water (Figure 1). Also, sulfides can be used to precipitate complexed metals in the presence of complexing agents such as ammonia, citrate and EDTA and over a broader pH range than possible for the hydroxide precipitation.3 A typical sulfide precipitation reaction is as follows ... 

Ammonia, acetylene, butadiene, butane, other petrolerrm gases, hydrogen, sodium carbide, turpentine, benzene, and finely divided metals Ammonia, methane, phosphine, and hydrogen sulfide Acetylene, hydrogen peroxide Isolate from everything... 

NIOSH REL (Chromium(VI)) TWA 0.025 mg(Cr(VI))/mh CL 0.05/15M SAFETY PROFILE Confirmed human carcinogen. Poison by subcutaneous route. Mutation data reported. A powerful oxidizer. A powerful irritant of skin, eyes, and mucous membranes. Can cause a dermatitis, bronchoasthma, chrome holes, damage to the eyes. Dangerously reactive. Incompatible with acetic acid, acetic anhydride, tetrahydronaphthalene, acetone, alcohols, alkali metals, ammonia, arsenic, bromine penta fluoride, butyric acid, n,n-dimethylformamide, hydrogen sulfide, peroxyformic acid, phosphorus, potassium hexacyanoferrate, pyridine, selenium. 

Many other examples of chemoselective enone reduction in the presence of other reducible functionalities have been reported. For instance, the C—S bonds of many sulfides and thioketals are readily cleaved by dissolving metals. " Yet, there are examples of conjugate reduction of enones in the presence of a thioalkyl ether group." " Selective enone reduction in the presence of a reducible nitrile group was illustrated with another steroidal enone. While carboxylic acids, because of salt formation, are not reduced by dissolving metals, esters" and amides are easily reduced to saturated alcohols and aldehydes or alcohols, respectively. However, metal-ammonia reduction of enones is faster than that of either esters or amides. This allows selective enone reduction in the presence of esters"" and amides - -" using short reaction times and limited amounts of lithium in ammonia. 

Movement through the phases is reflected by significant changes in leachate and gas quality. Nonconservative constituents of leachate (primarily organic in nature) tend to decompose and stabilize with time, whereas conservative constituents will remain long after waste stabilization occurs. Conservative constituents include various heavy metals, ammonia, chloride, and sulfide. 

CHROMIUM TRIHYDROXIDE (308-14-1) CrH204 A powerful oxidizer. Violent reaction with many materials, including reducing agents (explosion) hydrides, nitrides, and sulfides acetic acid, acetic anhydride acetone, alcohols, alkalis, alkali metals, ammonia, anthracene, arsenic, combustible materials dimethylformamide, ethers, ethyl alcohol fumes (ignition) finely divided metals hydrogen sulfide sulfuric acid organic matter peroxyformic acid, phosphorus, pyridine, selenium, sodium, sulfur, and other oxidizable materials. 

Water resource quality/ effluents BOD. suspended solids, salts, toxic metals, sulfates BOD, suspended solids, oil, metals, acids, phenol, sulfides, sulfates, ammonia, cyanides, effluents from wet gas scrubbers Organic chemicals, heavy metals, suspended solids, COD, cyanide Contamination of water by toxic chemicals, accidental spillage of toxic materia] Used effluent... 

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