Naphtha, straight-run

Straight-run asphalts Straight run naphthas Strain gauges Strainmaster S. strain NRRL 15496 Stratosphere Stratospheric ozone... 

Table 2. Properties of Straight Run Naphthas from Various Crude Oils...

In addition to straight run naphthas, 70—190°C cuts obtained by distillation from streams produced by cracking high boiling petroleum fractions can also be used as feed to reformers. Naphthas produced by hydrocracking are particularly suitable. 

Naphtha is a generic term normally used in the petroleum refining industry for the overhead liquid fraction obtained from atmospheric distillation units. The approximate boiling range of light straight-run naphtha (LSR) is 35-90°C, while it is about 80-200°C for heavy straight-run naphtha (HSR). ... 

Typical analyses of two straight-run naphtha fractions from two crude types... 

Figure 5.33 shows an example dataset of mixed hydrocarbons used as a petrochemical feedstock. These are straight run naphthas, which consist of a wide range of alkane, isoalkane, aromatic and naphthenic... 

Reforming Both thermal and catalytic processes are utilized to convert naphtha fractions into high-octane aromatic compounds. Thermal reforming is utilized to convert heavy naphthas into gasoline-quality aromatics. Catalytic reforming is utilized to convert straight-run naphtha fractions into aromatics. Catalysts utilized include oxides of aluminum, chromium, cobalt, and molybdenum as well as platinum-based catalysts. 

The economics of thermal reforming and hydroforming of sweet and sour heavy straight-run naphthas have been compared recently by McLaurin, McIntosh, and Kaufman (15). They concluded that the relative economics of the two processes were virtually the same for both feed stocks. 

Numbers of Debutanized Gasolines from Platforming and Thermal Reforming of Mid-continent Straight-Run Naphtha... 

Figure 3.8 shows an example dataset of mixed hydrocarbons used as a petrochemical feedstock. These are straight-run naphthas which consist of a wide range of alkane, alkene, aromatic and naphthenic hydrocarbons, mainly in the range of C4-C9. The conventional analytical method for naphtha analysis is temperature-programmed gas chromatography (GC), which can provide a full analysis including C-number breakdown, but which is rather slow for process optimisation purposes. 

In the process, the vacuum residuum is brought to the desired extraction temperature and then sent to the extractor where solvent (straight run naphtha, coker naphtha) flows upward, extracting soluble material from the down-flowing feedstock. The solvent-deasphalted phase leaves the top of the extractor and flows to the solvent recovery system where the solvent is separated from the deasphalted oil and recycled to the extractor. 

The predominant feeds for reforming are straight-run naphthas from cmde stills. Naphthas from catalyst crackers and naphthas from code stills are also used. Typical compositions are summarized in Table 5. Typical operating conditions for catalytic reforming are 1.135—3.548 MPa (150—500 psi),... 

Persian Gulf (PG) 90-l40°C cut straight run naphtha is hydrodesulfurised in naphtha pretreater and is being processed in the referred industrial reformer The pretreated naphtha was procured from the refinery and used as charge for pilot plant studies at UP It s characteristics are presented in Table 2... 

Distillation into nominally three cuts IBP-350°F straight run naphtha 350°-650°F mid-distillate 650°-850°F gas oil (where practicable). 

Hydrocracking of the mid-distillate and gas oil to produce naphtha and LPGs (3) hydrotreating of the straight run naphtha and hydro-crackate naphtha to remove heteroatoms and (4) reforming of the hydrotreated naphthas to maximize aromatics. 

With the possible exception of the SRC II straight-run naphthas, these Ce-Co reformates could be fed to a hydrodealkylator without first being extracted. However, it must be noted that hydrocracking, as evidenced by paraffin conversion, was not nearly as active as expected. In the event that a coal-derived naphtha contained a substantial portion of paraffin, particularly C6 paraffin, the aromatic content of the resultant reformate would be significantly less. 

There are basically three processes in usage today for the production of hydrogen or ammonia synthesis gas Steam Reforming for the conversion of light hydrocarbons from natural gas to straight run naphthas Partial Oxidation for heavy hydrocarbons and coal and Electrolysis of Water. 

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