High-purity nitrogen

In preparing elastomers by the two-step procedure, the entire quantities of LHT-240 and TDI were mixed in the resin flask under high-purity nitrogen for 2 hours at 50°C. Even without catalyst, this period was sufficient to obtain complete reaction, or essentially so, because of the relatively high reactivity of the para isocyanate group in the TDI. The... 

The checkers used high-purity nitrogen. If ordinary commercial nitrogen is employed, the oxygen should be removed by passing the gas through Fieser s solution. 

Sources of dry, high-purity nitrogen, air, and helium input to the TGA equipment... 

IMPORTANT NOTE Use high-purity nitrogen only, otherwise impurities of 02 will oxidize the lipids (see Critical Parameters). A multiport nitrogen evaporator equipped with a distribution manifold and water bath is highly recommended for this application (Fig. Dl.2.1). 

In a typical experiment, a solution of 1-48 g (0-01 mole) of phthalic anhydride in 8-05 ml (0-1 mole) of pyridine was pyrolyzed at 690° in dry, high-purity nitrogen flowing at the rate of 2-7 1/hr. Contact time was 20-2 sec. The products were distilled to recover 6-34 ml of pyridine. The distillation residue weighed 2-12 g, of which 0-06 g was removed for analysis by mass spectrometry. The remainder was dissolved in ether and separated into nitrogen bases (1-44 g) and hydrocarbons (0-62 g) by extraction with dilute hydrochloric acid. Analysis by gas chromatography, by comparison of retention times with authentic samples, gave the results shown in Table 9. 

For this technique to be effective, the adsorbing surface must be free from all impurities such as moisture, solvents, and other contaminants. Prior to measurement, the sample is outgased under either vacuum or high purity nitrogen, with or without... 

The Air Products technology will be able to recover almost 100% of the hydrocarbon off-gas from the slurry phase polyethylene process and more than 97% of the high-purity nitrogen that is used in degassing. Both of these gas streams will be recycled and re-used to reduce the VOC and NOx environmental emissions that are typically associated with flaring or burning plant off-gasses55. 

High purity nitrogen carrier gas was used as the carrier gas. 

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