Distillants, catalytic upgrading

About a year ago, you mentioned some hydrotreating of this full range of heavy distillate in doing some catalytic upgrading, and you mentioned that there were some plugging problems that developed in small bench-scale work, I believe, in from one to five days. At that time, you were looking for the possible source of that trouble. I haven t seen reports since then. I wondered if you have turned up an answer as to what caused that plugging or a solution that you could talk about. 

Ultralining a fixed-bed catalytic hydrogenation process to desulfurize naphthas and upgrade distillates by essentially removing sulfur, nitrogen, and other materials. 

Once the synthetic crude oils from coal and oil shale have been upgraded and the heavy ends converted to lighter distillates, further refining by existing processes need not be covered in detail except to note the essential character of the products. The paraffinic syncrude from oil shale yields middle distillates which are excellent jet and diesel fuel stocks. The principal requirements are removal of nitrogen to the extent necessary for good thermal stability of the fuels and adjustment of cut points to meet required pour or freeze points, limited by the presence of waxy straight-chain paraffins. The heavy naphtha from shale oil can be further hydrotreated and catalytically reformed to acceptable octane number, but with considerable loss of volume because of the only moderate content of cyclic hydrocarbons, typically 45-50%. On the other... 

Based on correlations, the naphthas from the shale oil hydrotreater can be readily upgraded to high-octane gasolines by catalytic reforming. The middle distillate fractions will require some additional hydrotreating... 

Our approach has been to hydrotreat the whole shale oil before distillation in this way, the entire stock is upgraded in this first catalytic step. Results support the conclusion that hydrodenitrification of whole shale oil is commercially feasible. 

Results showed that the two-stage TCH process could be used for upgrading Athabasca bitumen and for producing reformer naphtha feedstock, fuel oils, and catalytic cracking gas-oil feedstock. Product weight yields ranging from 86.4% to 93.0% were obtained. A 3 wt % CoO-15 wt % Mo03 on alumina catalyst was found to be sufficiently active to produce specification distillates. Comparison of various catalysts showed some differences in selectivities. However, extended life studies should be carried out to substantiate the differences. 

In present-day refineries, the fluid catalytic cracking (FCC) unit has become the major gasoline-producing unit. The FCC s major purpose is to upgrade heavy fractions, that is, gas oil from the atmospheric and vacuum distillation columns and delayed coker, into light products. Atmospheric gas oil has a boiling range of between 650-725°F.9... 

Catalytic cracking is the process of upgrading gas oil or even residual oil (heavy oil) to produce gasoline, distillates, light olefines, etc. Commercialized processes include fluid catalytic cracking (FCC), residual oil catalytic cracking (RFCC), and catalytic pyrolysis, etc. 

The H-Oil process is a catalytic hydrogenation technique that uses a one-, two-, or three-stage ebullated-bed reactor in which considerable hydrocracking takes place during the reaction. The process is used to upgrade heavy sulfur-containing crude oils, residual stocks, and low-sulfur distillates, thereby reducing fuel oil yield. 

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