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Sulphur store

Hexamethyldisilthiane (bis-trimethylsilyl sulphide) [3385-94-2] M 178.5, b 65-67 /16mm, 162.5-163.5 /750mm corr, 164 /760mm, d 0.85, n 1.4598. Dissolve in pet ether (b ca 40°), remove solvent and distilled. Redistilled under atmospheric pressure of dry N2. It is collected as a colourless liquid which solidifies to a white solid in Dry-ice. On standing for several days it turns yellow possibly due to liberation of sulphur. Store below 4° under dry N2. [JCS 3077 7950]. [Pg.391]

Sulphur dioxide gas is produced in the process from the combustion of sulphur under controlled conditions. Exposure to sulphur dioxide gas may occur due to leaks in the process or if the sulphur store accidentally catches fire. Leaks can be detected by placing the stopper of a bottle containing ammonium hydroxide close to the area of the suspected leak. Dense white fumes are released by the reaction of sulphur dioxide with ammonia. Continuous cycle sequential monitoring systems e.g. Gelman type are recommended for the early detection of sulphur dioxide leaks, particularly if the plant is located inside a building. [Pg.19]

M.p. I08-5 C. Ordinary DDT contains about 15% of the 2,4 -isomer, and is prepared from chloral, chlorobenzene and sulphuric acid. It is non-phytotoxic to most plants. It is a powerful and persistent insecticide, used most effectively to control mosquitoes in countries where malaria is a problem. It is stored in the bodies of animals and birds. [Pg.125]

This should be free from sulphur, and obtained in small containers so that a specimen is rapidly used it should be in dark bottles and stored in the dark. When withdrawing a specimen, the acid should be exposed to the air for as short a time as possible, as both air and light promote its decomposition to iodine. [Pg.499]

Prepare a solution of 41 g. of anhydrous palladium chloride (1) in 10 ml. of concentrated hydrochloric acid and 25 ml. of water (as in A). Add all at once 60 ml. of 6iV-sulphuric acid to a rapidly stirred, hot (80°) solution of 63 1 g. of A.R. crystallised barium hydroxide in 600 ml. of water contained in a 2-htre beaker. Add more 6iV-sulphuric acid to render the suspension just acid to htmus (5). Introduce the palladium chloride solution and 4 ml. of 37 per cent, formaldehyde solution into the hot mechanically stirred suspension of barium sulphate. Render the suspension slightly alkaline with 30 per cent, sodium hydroxide solution, continue the stirring for 5 minutes longer, and allow the catalyst to settle. Decant the clear supernatant hquid, replace it by water and resuspend the catalyst. Wash the catalyst by decantation 8-10 times and then collect it on a medium - porosity sintered glass funnel, wash it with five 25 ml. portions of water and suck as dry as possible. Dry the funnel and contents at 80°, powder the catalyst (48 g.), and store it in a tightly stoppered bottle. [Pg.951]

As with c -polyisoprene, the gutta molecule may be hydrogenated, hydro-chlorinated and vulcanised with sulphur. Ozone will cause rapid degradation. It is also seriously affected by both air (oxygen) and light and is therefore stored under water. Antioxidants such as those used in natural rubber retard oxidative deterioration. If the material is subjected to heat and mechanical working when dry, there is additional deterioration so that it is important to maintain a minimum moisture content of 1%. (It is not usual to vulcanise the polymer.)... [Pg.866]

Sulphuric acid is frequently made, stored and conveyed in lead. The corrosion resistance is excellent (see Figure 4.15) provided that the sulphate film is not broken in non-passivating conditions. Rupture of the film may be caused by erosion by high velocity liquids and gases containing acid spray. [Pg.731]

An example where reactant concentration is solely governed by corrosion considerations is in the production of concentrated nitric acid by dehydration of weak nitric acid with concentrated sulphuric acid. The ratio of HN0j H2S04 acid feeds is determined by the need to keep the waste sulphuric acid at > 70 Vo at which concentrations it can be transported in cast-iron pipes and stored after cooling in carbon-steel tanks. [Pg.16]

Notes. (1) For elementary students, it is sufficient to weigh out accurately about 1.7 g of sodium oxalate, transfer it to a 250 mL graduated flask, and make up to the mark. Shake well, Use 25 mL of this solution per titration and add 150mL of ca 1M sulphuric acid. Carry out the titration rapidly at the ordinary temperature until the first pink colour appears throughout the solution, and allow to stand until the solution is colourless. Warm the solution to 50-60 °C and continue the titration to a permanent faint pink colour. It must be remembered that oxalate solutions attack glass, so that the solution should not be stored more than a few days. [Pg.372]

When the experiment has been completed, clean the capillary as described above and then store it by inserting through a bored cork (or silicone rubber bung — normal rubber bungs which contain sulphur must be avoided) which is then placed in a test-tube containing a little pure mercury. Lower the mercury reservoir until drops no longer issue from the capillary, then push the end of the capillary into the mercury pool. [Pg.617]

A Fischer reagent had been made with pyridine, iodine, sulphur trioxide and formamide, instead of methanol. The bottle detonated after being stored for a couple of months. The authors put it down to the decomposition of formamide into ammonia and carbon oxide, which created the overpressure that caused the bottle to detonate. [Pg.343]

Moist diethyl sulphate was stored in an iron reservoir, which detonated after a little while. This accident was explained by the hydrolysis of the sulphate present that gives rise to the formation of sulphuric acid. By reacting with iron, sulphuric acid formed hydrogen that caused the overpressure responsible for the detonation. [Pg.348]

Toluene, the major solvent, was stirred for three days with several portions of sulphuric acid, washed, dried, and stored over calcium hydride on a vacuum rack. The toluene was distilled out immediately prior to the reaction. The dichlorides were vacuum distilled at the time of the reaction into three fractions, and the middle fraction, about 60% of the total, used. The dichlorides were obtained from Petrach, stored in a nitrogen glove bag and handled by syringe. [Pg.102]

The role of the iron-sulphur system of xanthine oxidase in the catalytic reaction is somewhat problematical. Nevertheless, it is clear, both from rapid freezing EPR (53) and from stopped-flow measurements monitored optically at 450 nm (58, 63) (where both iron and flavin are measured), that iron is reduced and oxidized at catalytically significant rates. Perhaps the best interpretation is that it functions as a store for reducing equivalents within the enzyme when this is acting as an oxidase, though it may well represent the main site of electron egress in dehydrogenase reactions (52). [Pg.117]

Peroxides, organic Phosphorus (white) Potassium chlorate Potassium perchlorate Potassium permanganate Silver Acids (organic or mineral), avoid friction, store cold Air, oxygen Acids (see also chlorates) Acids (see also perchloric acid) Glycerol, ethylene glycol, benzaldehyde, sulphuric acid Acetylene, oxalic acid, tartaric acid, fulminic acid (produced in ethanol — nitric acid mixtures), ammonium compounds... [Pg.165]

Hydrogen cyanide is highly endothermic and of low MW (AH°f (g) +130.5 kJ/mol, 4.83 kJ/g). A comprehensive guide to all aspects of industrial handling of anhydrous hydrogen cyanide and its aqueous solutions states that the anhydrous liquid is stable at or below room temperature if it is inhibited with acid (e.g. 0.1% sulphuric acid) [ ] Presence of alkali favours explosive polymerisation [2], In absence of inhibitor, exothermic polymerisation occurs, and if the temperature attains 184°C, explosively rapid polymerisation occurs [3], A 100 g sample of 95-96% material stored in a glass bottle shielded from sunlight exploded after 8 weeks [4], The explosive polymerisation of a 33 kg cylinder was attributed to lack of sufficient phosphoric acid... [Pg.153]

An amorphous form of sulphur which is insoluble in rubber. It is used in rubber compounds which have to be stored for some considerable time in the uncured state without loss of tack, e.g., repair materials for tyres and belting. Since this form of sulphur is insoluble in the rubber it cannot bloom to the surface. The use of insoluble sulphur also gives some degree of scorch control since it is inactive until it reverts to the soluble form. Insulation... [Pg.35]

Procedure Weigh 200 g sodium dichromate and transfer to a 2 Litre hard-boroslicate glass beaker. Dissolve it in 100 ml of water and cool in an ice-bath to about 10-15°C. Now, add to it 1500 ml of sulphuric acid (3 6 N) in small bits at intervals with constant stirring. Chromic acid mixture is extremely corrosive and hygroscopic and must be stored in closed glass-stoppered bottles. [Pg.51]

Earthquakes provide the ultimate test of the storage of incompatible chemicals and are sometimes followed by fires in chemical stores. Very few causes of ignition are found alkali metals halogen oxysalts in conjunction with strong acids and sulphuric or nitric acid and cellulose (wood flooring). These usually then ignite vapours of flammable solvents. [Pg.137]

Ammonium-N standard solution, 140 pg mM nitrogen - weigh 0.661 g ammonium sulphate (dried at 105°C for 1 h and cooled in a desiccator) into a 100-ml beaker and dissolve in ammonia-free water (distil deionized water acidified with sulphuric acid), transfer with washings to a 1-1 volumetric flask and make up to the mark with the ammonia-free water and mix. This should be stored in a refrigerator, but a quantity allowed to warm to room temperature in a stoppered container before use. [Pg.65]

Dissolve 1.8 g of ammonium molybdate in 700 ml of Dl water. Cautiously, while swirling, slowly add 22.3 ml of sulphuric acid. Add 0.05 g antimony potassium tartrate and dilute to 1 I with Dl water. Mix thoroughly and add 2 g of sodium dodecyl sulphate. Store in a dark bottle. Prepare fresh weekly. [Pg.235]

Add carefully 80 ml of cone, sulphuric acid to about 600 ml of Dl water and cool to room temperature. Dissolve 15 g of ascorbic acid and dilute to 1 I with Dl water and mix thoroughly. Store in a dark bottle in the refrigerator. The solution is stable for 1 week. [Pg.236]

In the fifth edition of his Cours de Chymie, Nicolas Lemery confused bismuth with zinc. Bismuth, said he, is a Sulphureous Marcassite that is found in the Tinn Mines many do think it is an imperfect Tinn which partakes of good store of Arsenick its pores are disposed in another manner than those of Tinn, which is evident enough because the Menstruum which dissolves Bismuth cannot intirely dissolve Tinn. There is another sort of Marcassite, called Zinch, that much resembles Bismuth.. . Marcassite is nothing else but the excrement of a Metal, or an Earth impregnated with Metallick parts. The Pewterers do mix Bismuth and Zinch in their Tinn to make it found the better (52). [Pg.106]

Understanding the storage capacity of the metal oxide material and the N02 adsorption rate is therefore also very important. Furthermore, oxides of sulphur in the exhaust gas, formed from combustion of sulphur compounds in the fuel (or lubricant oil), are stored in a similar manner. Since sulphates are thermodynamically more stable than the corresponding nitrate, this results in a reduction in the NOx storage capacity of the LNT. [Pg.89]


See other pages where Sulphur store is mentioned: [Pg.1010]    [Pg.32]    [Pg.1010]    [Pg.32]    [Pg.555]    [Pg.421]    [Pg.550]    [Pg.314]    [Pg.263]    [Pg.132]    [Pg.311]    [Pg.1435]    [Pg.525]    [Pg.308]    [Pg.84]    [Pg.69]    [Pg.432]    [Pg.50]    [Pg.250]    [Pg.314]    [Pg.342]    [Pg.436]    [Pg.50]   
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