Inert gases nitrogen

Fig. 3.17 Pressure scale of Federal Physical-Technical Institute (PTB), Berlin, (status as at August 1984) hr inert gases, nitrogen and methane...

Apart from these common pretreatments, special pretreatments are necessary in some cases. For example, a small amount of basic impurity (possibly triethyl-amine) in PC is not removed even by repeated distillations. However, if we add p-toluenesulfonic acid to neutralize the basic impurity, we can remove it easily by distillation (Section 10.4). As another example, volatile impurities in PC can be removed only by bubbling inert gases (nitrogen or argon) for many hours. 

Of the chlorine oxides only chlorine dioxide has achieved industrial significance. It is a gas at room temperature. As a result of its explosive properties, it can only utilized in situ and even then has to be diluted with inert gases (nitrogen, carbon dioxide) to 10 to 15% (by volume). 

Properties Colorless, fuming liquid. D 2.466 (25C), fp —61C, bp 40.5C, vap press (21.1C) 7 psi. Reacts with every known element except inert gases, nitrogen, and oxygen. 

Natural Gas. Natural gas is the simplest source of hydrocarbon raw materials for chemicals since it consists of a small number of compounds which are easily separated. Nonhydrocarbon constituents include water vapor (up to 2.5% by volume, the saturation value), carbon dioxide (up to 95% from some wells in Mexico, New Mexico, and Colorado), inert gases (nitrogen and helium), and sulfur compounds (largely hydrogen sulfide). The hydrocarbon constituents of natural gas contain up to 8 carbon atoms. Wet natural gas contains larger proportions of the heavier hydrocarbons in this range. 

Ineigen is an attractive product in several ways. It is a blend of three inert gases, nitrogen, argon, and carbon dioxide and is discharged as are the halons. The concentration required to be effective is low... 

The product distribution in methane chlorination is shown in Fig. 97 as a function of the ratio chlorine methane. This distribution can be influenced by working with a high methane to chlorine ratio, by admixing inert gases (nitrogen), recycled hydrogen chloride or monochloromethane into the feed gas, and by proper temperature control. 

Many austenitic stainless steels have failed during downtime because the piping or tubes were not protected from chlorides. A good precaution is to blanket austenitic stainless steel piping and tubing during downtime with an inert gas (nitrogen). 

To maintain a low level of inert gas (nitrogen) a part of the recirculating gas stream is withdrawn. The sulfur dioxide is washed out by water. The resulting aqueous solution is warmed, and the sulfur dioxide stripped by a stream of oxygen and fed back to the reactor. 

All other reactions were carried out under dry inert gas (nitrogen or argon). Reagents were distilled before use. Octaphenylcyclotetrasilane (mp=322 C) was prepared from diphenyldichlorosilane and Li in 27% yield. 

A solution of 18 g (68 mmol) of commercial ruthenium trichloride hydrate (Johnson Matthey, 40 3% ruthenium) in a mixture of isoprene (680 mL) and 2-methoxyethanol (280 mL) is heated at reflux for 10 days under inert gas (nitrogen or argon). The purple crystalline product is collected in a medium-porosity sintered-glass funnel, washed with diethyl ether, and dried in vacuo yield 19.9 g (95%). 

If complete saponification is achieved, remove the rubber stopper from the inlet tube of the flask and attach a source of inert gas (nitrogen or carbon dioxide) to the tube. After allowing t "ip gac rrt flow for 3 mins stiti (whils cooninuin the flow of gas until, the end of test) in 2-ml increments 40ml of the 0.2N titanous chloride soln, swirling the flask after each addn. Then swirl the flask for another 15 secs and add 25ml of 15% HC1 soln, followed by 5ml of 20% ammonium thiocyanate soln... 

The equipment can usually be constructed of carbon steel except for the hydrolysis vessel, which is usually glass-lined to avoid corrosion by aqueous acids. All vessels must be supplied with an inert gas (nitrogen or argon) for purging and blanketing and are vented to release off-gases. It is imperative that the reaction vessel be protected with a rupture disk. 

Less commonly, other experimental conditions may need to be controlled. For example, it may be that the presence of O2 in solution affects the reaction, in which case stock solutions and the reaction mixture should be flushed and then kept saturated with an inert gas (nitrogen or, preferably, argon). For reactions in nonaqueous solvents, of course, water may need to be rigorously excluded. And sometimes, a chemical process is affected by light if any of the species involved is light sensitive. In this event, stock solutions and the... 

Caution. l,3-Diaza-2-boracycloalkanes are moisture-sensitive and react readily with protonic materials. Alcohols, in particular, may occasionally cause an explosive solvolysis reaction on contact with these heterocycles. The compounds should be handled under dry inert gas (nitrogen or argon) to avoid their contamination. The possible toxicity of boron compounds has not yet been explored. 

A number of utilities are required to run a chemical plant cooling water, steam at various pressure levels, electricity, refrigeration, air, and inert gas (nitrogen). Those utilities associated with providing power (electricity and steam) normally generate both electricity and process steam. The two most common power plants are ... 

Ozmotech have developed a Thermofuel process whereby waste plastic is converted into diesel by thermal degradation in the absence of oxygen. In this process the plastic waste is first melted and then cracked in a stainless steel chamber at a temperature of 350-425°C under inert gas (nitrogen). The catalytic reaction tower is designed in such a way that hot pyrolytic gases take a spiral or zigzag path to maximize contact area and time with the metal catalyst. The metal catalyst cracks hydrocarbon chains longer than C25 and reforms chains shorter than Ce. This leads to the formation of saturated alkanes. 

Use an air or inert gas (nitrogen) capillary bleed during vacuum distillation (seep. 110). 

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