Light catalytic cycle oil

A follow up paper reported on the substrate preference of the strain ECRD-1 [86], Two different diesel oils were studied LCCO (light catalytic-cycle oil), which is heavily hydrotreated and OB oil, (not treated by HDS). Sulfur molecules ranging from Cl to C4 DBTs and C2-C7 BTs were identified in the oils and assessed before and after treatment (Fig. 15). 

Hydrocracker Trickle phase catalytic Convert gas oils, coker gas oil, and light catalytic cycle oil to lighter products... 

A similar catalyst was used in the study of Diez et aP, deactivated with either a light catalytic cycle oil or a coal residuum. As the reaction temperature was increased from 335°C to 395°C, the amount of coke increased from 1.5 wt% to 3 wt% and the aromaticity from 40% to 70%, as measured by CP MAS NMR. The aromaticity was calculated from the percentage of sp carbon signal. When using the coal residuum as feed, the aromaticity increased up to 73% and the coke content up to 10%, at 415°C. 

FIGURE 13.35 Gas chromatographic-microcoulometric chromatograms of light catalytic cycle oil (LCCO) demonstrating the removal of benzotheophenes by hydrotreating. (Reproduced with permission of the author, Reference 100.)... 

Kinetic Study—Dibenzothiophene Desulfurization. Earlier work at Amoco by Frye and Mosby (8) studied the rate of reaction of single sulfur compounds in light catalytic cycle oil. Conclusions from that study were (1) the reaction kinetics are first order in hydrogen and reactant sulfur (2) hydrogen sulfide inhibits the reaction (3) overall energy of activation is around 28-30 kcal. 

In contrast to white oil, light catalytic cycle oil is highly aromatic. These aromatics con ietitively adsorb and inhibit the desulfurization reaction. At high aromatics concentration, the dlbenzothlophene adsorption would be masked by aromatic adsorption. Apparent first order kinetics with respect to dlbenzothlophene would then be observed. 

The gas oil cut from catalytic cracking called Light Cycle Oil (LCO), is characterized by a very low cetane number (about 20), high contents in aromatics, sulfur and nitrogen, all of which strongly limit its addition to the diesel fuel pool to a maximum of 5 to 10%. 

The thermal and catalytic cracking of PP, PS, and SBR waste, dissolved in light cycle oil, was studied in a riser simulator. 19 refs. 

Lower dilution levels did not allow sufficient depolymerlzatlon and higher dilution caused excessive depolymerlzatlon In the aged solutions. Pillared clays prepared from aged dilute solutions had an enhanced microstructure which showed an Increased activity for selectively cracking large molecules to the light cycle oil range. This microstructure Is lost In the presence of steam which also reduces the formation of catalytic coke. Addition of rare earth zeolite to pillared clay can partially overcome the effects of this loss of microstructure. 

Catalytic evaluation of the different pillared clays was performed using a microactivity test (MAT) and conditions described in detail elsewhere (5). The weight hourly space velocity (WHSV) was 14-15 the reactor temperature was 510 C. A catalyst-to-oil ratio of 3.5-3.8 was used. The chargestock s slurry oil (S.O., b.p. >354 C), light cycle oil (LCGO, 232 C < b.p. <354 C) and gasoline content were 62.7 vol%, 33.1 vol% and 4.2 vol% respectively. Conversions were on a vol% fresh feed (FF) basis and were defined as [VfVp/V ] x 100, where is the volume of feed... 

Figures 1 and 2 show that there are five major products obtained from a catalytic cracking operation. These products are 1) light products 2) gasoline 3) light cycle oil 4) slurry or decant oil and 5) coke. The light products are those which have a boiling point below 170°F, gasoline has a boiling point of 170°F-430°F, light cycle oil has by definition here a boiling point of 430°F-630°F, slurry or...

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