Heavy oils A-grade

Figure 27.5 Photographs of A-grade heavy oil with exfoliated graphite, (a) Heavy oil floating on water, (b) 1 min after addition of a lump of exfoliated graphite, and (c) after recovery of oil-sorbed exfoliated graphite by filtration.

Figure 27.6 Dependences of sorption capacity for the A-grade heavy oil on hulk density of carbon sorbents.

Figure 27.7 Relation between sorption capacity of difierent carbon sorbents for the A-grade heavy oil and pore volume measured by using a new dilatometer for mercury porosimetry.

Figure 27.13 Sorption curves of carbon sorbents with different bulk densities for the A-grade heavy oil.

Figure 27.17 Cyclic performance of carbon sorbents for tbe A-grade heavy oil by filtration under suction.

Toyoda, M., Dogawa, N., Seki, T., et al. (2001). Sorption and recovery of A-grade heavy oil by using exfoliated graphite packed in plastic bag - trial for practical applications. TANSO, 166—9 (in Japanese). 

FIGURE 4.5 Appearance of sorption and recovery of heavy oil on water using exfoliated graphite (EG), (a) A-grade heavy oil floating on water, (b) 2 min after the addition of EG with less amount of oil than the sorption capacity of EG, (c) heavy oil with more than the sorption capacity of EG added, and (d) after transfer of EG after sorbing heavy... 

A piece of exfoliated graphite was placed on the snrface of A-grade heavy oil directly it was picked up by using a stainless steel mesh after 2 h of immersion and then kept for 1 h to drain off the excess oil. In the case of viscous C-grade heavy oil, immersion for 15 h and draining-off for 3 h was employed. 

In Figure 4.6, sorption capacities of two exfoliated graphite samples with slightly different bulk densities (EG-1 and EG-2) are compared on four grades of heavy oil (Table 4.1). In the case of A-grade heavy oil, up to 83 kg was sorbed into 1 kg of the exfoliated graphite EG-1, whose bulk density was 6 kg/m. This sorption capacity is much higher than that of poly(propylene) nonwoven web, which has... 

FIGURE 4.7 Dependence of heavy oil sorption capacity of exfoliated graphite on its bulk density, (a) A-grade heavy oil, (b) B- and C-grade heavy oils and crude oil. 

When A-grade heavy oil was dropped onto one end of this water-saturated exfoliated graphite, water was observed to come out from another end of the... 

FIGURE 4.14 Water coming out from water-saturated exfoliated graphite by dropping A-grade heavy oil on its top. 

In Figures 4.19a through 4.19c, the plots of versus t /2 for A-grade heavy oil are shown for three carbon sorbents with different bnik densities exfoliated graphite, carbonized fir libers, and carbon fiber felt. The sorptivity depends... 

FIGURE4.17 Time to reach 50% of mass increase saturation, f versus bulk density of exfoliated graphite, (a) A-grade heavy oil and (b) C-grade heavy oil. 

FIGURE 4.26 SEM images of the surface of wormlike particles of exfoliated graphite after sorption of heavy oil. (a) After sorption of A-grade heavy oil, (h) after recovering hy suction filtration, (c) after sorption of C-grade heavy oil, and (d) after suction filtration. 

A-grade heavy oil could be recovered from fir fibers carbonized at 900°C by simple filtration with mild suction (5 kPa) and the fibers could be reused, although the sorption capacity did decrease with cycling, as shown in Figure 4.28. 

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