Hydrocarbon trace

Among the inexhaustible plant resources for the production of activated carbon, we have the nutshell, which can be transformed by pyrolysis and activation with overheated water vapour. In this example, activated carbon has been used to retain some hydrocarbon traces from water using a batch reactor. The interest here is to... 

The third atmospheric technique analyses the residual liquid and/or condensate hydrocarbon traces on aerosols carried into the atmosphere by thermals (Barringer, 1981). The aerosols are created by gas bubbles which exsolve into the atmosphere from the sea in areas where microseeps create gas bubbles which reach the sea surface. The aerosols are concentrated from large volumes of air and collected by an airborne cyclone sampler carried aboard an aircraft which is flown at 30 m (100 feet) above the sea surface. Hydrocarbons adsorbed on the aerosols are measured by a flame ionisation detector which yields a total hydrocarbon signal. This system is claimed to produce... 

Chemical Name Petroleum Representative Chemicals Aliphatic, aromatic, paraffinic hydrocarbons Naphthenic hydrocarbons Asphaltic hydrocarbons Trace metals Chemical Abstracts Service Registry Number CAS 8002-05-9... 

The aqueous solution rich in ethylene oxide is sent to purification. It passes through a stripping column, which operates under vacuum and separates the ethylene oxide at the top. The aqueous effluent leaving at the bottom is recycled to the absorption stage. It can be treated in an auxiliary unit to recover the glycol it contains. The top effluent which, in addition to carbon dioxide, contains acetaldehyde and hydrocarbon traces, is sent to two distillation columns in series, one for dehydration ( = 20 trays), and the second for purification (S 50 trays). These columns produce high-purity ethylene oxide with a very low acetaldehyde content. The product is stored in liquid form in tanks under nitrogen pressure. 

Martin, P. H. and Guenther, A. B. (1995). Insights into the dynamics of forest succession and non-methane hydrocarbon trace gas emissions. 

The FID traces in Figure 7 compare the total hydrocarbon traces for diesel lube oil as a function of temperature and in a gas stream of either helium (nonoxidizing) or 10% O2 in helium (lean). In the bottom curves it can be seen that with no catalyst present diesel lube vaporizes into either gas stream between 100 and 200°C, well below its median simulated... 

Is it important to characterize the Cg+ hydrocarbon traces before estimating their effect on a calibration gas ... 

Major applications of the absorption processes are the removal of acid gas components such as CO2 and H2S from gas mixes. Cases are not infrequent, however, in which other raw gas components such as higher hydrocarbons, trace impurities (metal carbonyls, NH3) or steam are eliminated either alone or in combination with acid gas components. Absorption processes, which by their very essence are gas separation processes, are as a rule used for gas purification, i.e. undesired components are eliminated fix>m a gas mix without significantly changing its pressure. Some absorption processes are, however, used to recover individual gas components. In these processes, the normally larger undesirable portion of the gas mix is left at absorption pressure while the desired gas component, after it has been desorbed, is usually obtained at ambient pressure. 

Trace elements, polycyclic aromatic hydrocarbons Trace metals, sulfides, ammonia, organics, phenols, minerals... 

Using the same conditions as were used for identification of peaks, record the peaks of all compounds of interest at a maximum sensitivity in a manner to allow measurement of the area of each hydrocarbon trace component. 

Measure the area of each hydrocarbon trace peak and the area of the butadiene peak in the standard. Use acetylene in the standard as comparison for ethylene and acetylene in the sample. Use butadiene in the standard as comparison for the other trace compounds in the sample. 

Bias—Since there is no accepted reference material suitable for determining the bias for the procedure in Test Method D 2712 for measuring hydrocarbon traces, no statement on bias is being made. 

D 2712 Test Method for Hydrocarbon Traces in Propylene Concentrates by Gas Chromatography ... 

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