Sulfur, insoluble

Insoluble sulfur Insoluble ([Pg.4611]

Three vulcanizing agents And extensive use in the rubber industry sulfur, insoluble sulfur, and peroxides. The chemistry of peroxides has been reviewed in Chapter 7. Rhombic sulfur is the most common form of sulfur used in the rubber industry and, other than normal factory hygiene and operational procedures, does not require any special handling or storage. Sulfur is soluble in natural rubber at levels up to 2.0 phr. Above this concentration, insoluble sulfur must be used to prevent migration of sulfur to the compound surface that is, sulfur bloom. [Pg.454]

Crystamet 1020] Crystamet 2040] Crystamet 3080. See Sodium metasilicate pentahydrate Crystex 60] Crystex Regular. See Sulfur, insoluble... [Pg.1095]

Boron trifluoride Diethyl toluene diamine Resorcinol diglycidyl ether Toluene bis (dimethyl urea) preservation storage, apples Diphenylamine preservation, building tack Sulfur, insoluble preservation, food Catalase... [Pg.5561]

Sodium polysulfide sulfur mfg., fluorinated Triethylamine tris (hydrogen fluoride) sulfur migration inhibitor, rubber Sulfur, insoluble... [Pg.5760]

Sulfur Sulfur chloride Sulfur, insoluble Tetrabutyl thiuram disulfide Tetramethylthiuram disulfide vulcanizing agent, rubber compounds Bis-(3-(triethoxysilyl) propyl) tetrasulfane vulcanizing agent, SBR Alkyl phenol disulfide 1,1-Di (t-butylperoxy)-3,3,5-trimethyl cyclohexane vulcanizing agent, secondary rubber Tellurium... [Pg.5857]

Struktol SU 50 Struktol SU 109 Struktol SU 135 Sulfur, insoluble (polymer)... [Pg.6406]

Neutralization Fatty acids, phospholipids, pigments, trace metals, sulfur, insoluble matter... [Pg.136]

Stabilized insoluble sulfur Insoluble sulfur Amorphous sulfur Stabilized amorphous sulfur Polymeric sulfur Stabilized polymeric sulfur... [Pg.267]

Sulfur is pale yellow, odorless, brittle solid, which is insoluble in water but soluble in carbon disulfide. In every state, whether gas, liquid or solid, elemental sulfur occurs in more than one allotropic form or modification these present a confusing multitude of forms whose relations are not yet fully understood. [Pg.38]

If the chemist wants to know whether her final product is bromo-safrole and not just a bunch of unreacted safrole there is a simple little test she can do. Safrole is soluble (will dissolve in) cold concentrated sulfuric acid. But bromosafrole is insoluble in it. So the chemist can take a shot glass full of straight-from-the-bottle 96% H2SO4 and place it in the freezer until it s ice cold. Then she takes it out and drops a few drops of mystery product into it. If the oil dissolves then the stuff is unreacted safrole. If the oil drops to the bottom and does not dissolve it s the goods. [Pg.146]

A typical example is total monomers. 100 sodium stearate, 5 potassium persulfate, 0.3 lauryl mercaptan, 0.4 to 0.7 and water, 200 parts. In this formula, 75 parts of 1,3-butadiene and 25 parts of 4-methyl-2-vinylthiazole give 86% conversion to a tacky rubber-like copolymer in 15 hr at 45°C. The polymer contains 62% benzene-insoluble gel. Sulfur analysis indicates that the polymer contains 21 parts of combined 4-methyl-2-vinylthiazole (312). Butadiene alone in the above reaction normally requires 25 hr to achieve the same conversion, thus illustrating the acceleration due to the presence of 4-methyl-2-vinylthiazole. [Pg.398]

In the outdoor environment, the high concentrations of sulfur and nitrogen oxides from automotive and industrial emissions result in a corrosion having both soluble and insoluble corrosion products and no pacification. The results are clearly visible on outdoor bronze sculpture (see Airpollution Exhaust CONTROL, automotive Exhaust conthol, industrial). [Pg.425]

The longer perfluoroalkanesulfonic acids are hydroscopic oily Hquids. Distillation of the acid from a mixture of its salt and sulfuric acid gives a hydrated mixture with melting points above 100°C. These acids show the same general solubiUties as trifluoromethanesulfonic acid, but are insoluble in ben2ene, heptane, carbon tetrachloride, and perfluorinated Hquids. AH of the higher perfluoroalkanesulfonic acids have been prepared by electrochemical fluorination (20). [Pg.315]

Ranitidine. Ranitidine hydrochloride [66357-59-3] (Zantac) is a white to pale yellow granular substance. It is freely soluble in water and acetic acid, soluble in methanol, sparingly soluble in ethanol, and practically insoluble in chloroform. It has a slightly bitter taste and a sulfur-fike odor. It may be made by the method described in Reference 5. [Pg.199]

Inorganic Methods. Before the development of electrolytic processes, hydrogen peroxide was manufactured solely from metal peroxides. Eady methods based on barium peroxide, obtained by air-roasting barium oxide, used dilute sulfuric or phosphoric acid to form hydrogen peroxide in 3—8% concentration and the corresponding insoluble barium salt. Mote recent patents propose acidification with carbon dioxide and calcination of the by-product barium carbonate to the oxide for recycle. [Pg.478]

Specifications and Standards, Shipping. Commercial iodine has a minimum purity of 99.8%. The Committee of Analytical reagents of the American Chemical Society (67) and the U.S. Pharmacopoeia XXII (68) specify an iodine content not less than 99.8%, a maximum nonvolatile residue of 0.01%, and chlorine—bromine (expressed as chlorine) of 0.005% (ACS) and 0.028% (USP), respectively. In the past these requirements were attained basicaHy only by sublimation, but with processing changes these specifications can be met by direct production of iodine. Previously the impurities of the Chilean product were chiefly water, sulfuric acid, and insoluble materials. Improvements in the production process, and especiaHy in the refining step, aHow the direct obtainment of ACS-type iodine. Also, because of its origin and production process, the Chilean iodine has a chlorine—bromine impurity level of no more than 0.002%. [Pg.364]

AH of the [Fe(CN)3] salts maybe considered salts of ferrocyanic acid or tetrahydrogen hexakiscyanoferrate [1712647-5], H4[Fe(CN)3], a strongly acidic, air-sensitive compound. It is soluble in water and alcohol but is insoluble in ether. It can be prepared by precipitation of an etherate by adding ether to a solution of [Fe(CN)3] that was acidified with concentrated sulfuric acid. Removal of the ether of solvation affords a white powder which is stable when dry but slowly turns blue in moist air because of Pmssian Blue formation. [Pg.435]

Biacetyl is produced by the dehydrogenation of 2,3-butanediol with a copper catalyst (290,291). Prior to the availabiUty of 2,3-butanediol, biacetyl was prepared by the nitrosation of methyl ethyl ketone and the hydrolysis of the resultant oxime. Other commercial routes include passing vinylacetylene into a solution of mercuric sulfate in sulfuric acid and decomposing the insoluble product with dilute hydrochloric acid (292), by the reaction of acetal with formaldehyde (293), by the acid-cataly2ed condensation of 1-hydroxyacetone with formaldehyde (294), and by fermentation of lactic acid bacterium (295—297). Acetoin [513-86-0] (3-hydroxy-2-butanone) is also coproduced in lactic acid fermentation. [Pg.498]

Acid Oxidation. Reactions of lead with acid and alkaUes are varied. Nitric acid, the best solvent for lead, forms lead nitrate acetic acid forms soluble lead acetate in the presence of oxygen sulfuric acid forms insoluble lead sulfate. Sulfuric acid is stored in containers with chemical or acid-grade lead. Lead dissolves slowly in HCl, but in the presence of aqueous alkaUes forms soluble plumbites and plumbates. [Pg.33]

Copper-containing lead alloys undergo less corrosion in sulfuric acid or sulfate solutions than pure lead or other lead alloys. The uniformly dispersed copper particles give rise to local cells in which lead forms the anode and copper forms the cathode. Through this anodic corrosion of the lead, an insoluble film of lead sulfate forms on the surface of the lead, passivating it and preventing further corrosion. The film, if damaged, rapidly reforms. [Pg.60]

Lead shows excellent resistance to phosphoric and sulfuric acid in almost all concentrations and at elevated temperatures, as well as to sulfide, sulfite, and sulfate solutions. The corrosion film is insoluble lead sulfate which rapidly reforms if it is damaged. Lead is also resistant to chlorides, fluorides, and bromates at low concentrations and low temperatures. However, because lead is soluble in nitric and acetic acids, it is not resistant to these acids. [Pg.63]

The excellent corrosion-resistant lead dioxide, Pb02, film formed on anodes and lead—acid battery positive grids in sulfuric acid has enabled lead insoluble anodes and lead—acid batteries to maintain the dominant positions in their respective fields. [Pg.63]

Determination of Lignin Content. Lignin content in plants (wood) is determined by direct or indirect methods (21). The direct method includes measurement of acid-insoluble (ie, Klason) lignin after digesting wood with 72% sulfuric acid to solubilize carbohydrates (22). The Klason lignin contents of representative lignifted materials are shown in Table 2. [Pg.140]

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