Maximum liquid yields

To produce the maximum yield of finished gasoline in a hydrocracker-reformer combination, the hydrocracker should be operated to give maximum liquid yields, followed by a modem low pressure catalytic reformer to give the desired octane improvement (6). More severe hydrocracker operation produces higher octane naphtha but leads to an increase in the production of butanes with reduced yields of finished... 

An inspection of the liquid yields as functions of the radiative heat flux reveals that the higher the char yields are the lower the liquids. The maximum liquid yields, attained for applied heal fluxes of 49-69kW/m vary from about 56-57% (beech, Douglas fir and pine) to 52% (redwood) and 47% for chesmut. Hence, the wood variety may cause variations in the optimal liquid yields up to 10% of the initial dry wood mass. 

MISSION XII. SELECTED SUMMARY DATA WOOD TO OIL FOR DIRECT COMBUSTION AND CHAR VIA PYROLYSIS (MAXIMUM LIQUID YIELD)... 

All experimental results given were obtained at conditions of close to optimal feed rate, particle size and residence time for maximum liquid yield at the stated temperatures, as determined by over 200 bench scale runs and 90 pilot scale runs. These optimal conditions are those shown in Table I, that is, 480 to 520 C, 0.5 to 0.7 seconds apparent residence time and a maximum particle size of 1... 

This is equivalent to saying that the high pressure p2 which minimizes A2 is the pressure at which the Joule-Thomson coefficient is zero for a temperature of. In other words, for maximum liquid yield, point 2 on Fig. 4.4c should... 

In this study, an attempt was given to produce bio-oil through slow pyrolysis of rice husk (RH) at different heating rates in order to determine the optimum reaction condition that will give maximum liquid yield. The characteristics of bio-oil produced at different heating rates are then analyzed. Apart from that, the properties of bio-oil that was produced at optimum operating condition are compared with those in literature. 

In order to establish safe values for velocity-diameter product, various studies have been made to determine the minimum liquid surface potential that will result in an incendive discharge in the presence of a grounded electrode. Studies reviewed in [8] showed that for credible charging conditions, liquids must be negatively charged to yield incendive bmsh discharges. The consensus has been that to avoid incendive discharges the maximum liquid... 

The combined filtrates containing benzonitrile oxide are transferred to a 1-1. round-bottomed flask, treated immediately with 13.9 g. (0.1 mole) of N-sulfinylaniline added in one portion, with swirling, and set aside protected from moisture, while the temperature reaches a maximum of 33-34° (usually IS minutes). The mixture is then heated to reflux, protected from moisture, in a temperature-controlled oil bath for 3-5 hours. Continuous evolution of sulfur dioxide takes place during this period at the end of which the mixture is cooled and evaporated under reduced pressure (Note 3) at 70-80° to remove the solvent. The residual dark brown liquid is transferred to a 50-ml., pear-shaped distilling flask (Note 13) and heated, protected from moisture, at 110° for 30 minutes to complete the decomposition. It is then cooled and distilled under high vacuum (Note 14). Unchanged N-sulfinylaniline (2.0-2.5 g.) distills over at 45-50° (0.1-0.2 mm.). A second fraction (1.2-1.5 g.) is collected until the temperature reaches 112° (Note 15) then diphenyl carbodiimide is collected at 114-117° (0.1-0.2 mm.) as a clear yellow liquid yield 10.5-10.8 g. (54-56%) (Note 16) 1.6355 ... 

A report on the continuous flash pyrolysis of biomass at atmospheric pressure to produce liquids indicates that pyrolysis temperatures must be optimized to maximize liquid yields (36). It has been found that a sharp maximum in the liquid yields vs temperature curves exist and that the yields drop off sharply on both sides of this maximum. Pure cellulose has been found to have an optimum temperature for liquids at 500°C, while the wheat straw and wood species tested have optimum temperatures at 600°C and 500°C, respectively. Organic liquid yields were of the order of 65 wt % of the dry biomass fed, but contained relatively large quantities of oiganic acids. 

Yields of BTX and benzene peaked at about 1273°K whereas, the maximum ethylene yields were obtained at about 1100°K. The mass balances and yields of the gaseous and liquid products at one condition, 1273°K for 2 s, are given in Table 2. 

Between the time a liquid film is first formed, until it thins to an equilibrium black film, the thickness can be measured by techniques based on the interference of light. For monochromatic light, the intensity of light, IR, reflected at angle 8 from a fluid film compared to the maximum intensity yielded by constructive interference, I0, enables the determination of the film thickness, t, as ... 

Table 4 summarizes the results of the liquid yield and conversion from SCFE of Butia coal with pure toluene at 623 K and at 3, 4 and 5 moLl 1 solvent density. The liquid yield and conversion figures are again lower than those reported in the literature for different coals. The conversion reached a maximum at 4 mol.1 1 this effect has been shown in the literature [8], though at higher pressures. More investigation is being carried out to clarify this effect. Since the experiments were accomplished at constant temperature - assuring the same depolymerization/thermolysis of the coal structure, the increase in the liquid yield and conversion could be attributed to an enhancement in solvent density (solvent power). 

The maximum conversion obtained was 21.7% with 5 mol% tetralin, and 6.0% liquid yield with pure toluene at 10.9 MPa and 623 K. These figures are rather small when compared to literature data, being necessary to investigate different levels of thermal depolymerization and different solvents to optimize the conversion of the high-ash sub-bituminous Butia-coal. High levels of sulfur reduction were observed - up to 44%, and it has been also shown that the dessulfurization of the coal under study is selective with regard to the solvent mixture. 

This volume is comparable to the volume of the foam nonpolyhedral part (5 -layer, where 5 = 2a/pgR). However, the volume of this nonplolyhedral part cannot be estimated accurately because of the lack of an analytical n(H) dependence for a nonpolyhedral foam. The different estimates of the maximum liquid volume in the whole foam (integrating from 0 to °°) yield values... 

The maximum gas yield reaches 65% at 650°C whereas the carbon deposit increases up to 20-30%. These results show that the liquid yield decreases more rapidly than by flash pyrolysis. By a two-stage pyrolitic gasification process (450 and 800°C), it is possible to improve the quality of the gaseous products and the gas yield. In these conditions, the gas yield reaches 74% [22]. 

How the waste feed particle size infinenced the yields were investigated in runs at 825°C, the temperature giving the maximum styrene yield in the first set of experiments. As depicted in Figure 23.10, the coarsest size (300-212 p,m) rendered respectively 42% solid, 29% liquid, and 29% gas yields. As the particles became finer the solid yield diminished steadily to about 34% at less than 75 p,m. In contrast the gas yield increased monotonically to 38%. The liquid yield seemed little affected by the feed particle size. The total conversion rose from 58 to 66% because of its gas contribution. 

To a bright red solution of 0.56 g (ca. 2 inmol) of Niicodi, in 77.4 g (0.90 mol) of melhyl acrylate at 20"C are added 48.6 g (0.90 mol) of — 78 C-cooled methylenecyclopropane. dropwisc over 3 h. The reaction mixture is allowed to warm up to a maximum of 70 3C (cooling bath used if necessary) and the solution becomes dark red. After a further 2 h stirring, during which time the reaction temperature returns to 25 JC. the product is isolated by distillation as a colorless liquid yield 115.2 g (92%) bp 54 JC (12 Torr). 

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