Abstract: Oxygen compounds are removed, e.g., by extraction, from a coal liquid prior to its hydrogenation. As a result, compared to hydrogenation of such a non-treated coal liquid, the rate of nitrogen removal is increased.

Abstract: An improvement in the solvent extraction of nonhydrocarbons from a synfuel liquid, e.g., shale oil, involves that the extract from the extractor, rather than being recycled directly back to the extractor, is first hydrotreated. A further improvement involves that a portion of the hydrotreated extract is fractionated and a light fraction is returned to the extractor. Use of the hydrotreated extract as recycle increases the efficiency of the extractor. A still further improvement involves the use as a selective solvent of one of the following: dialkylformamide, aldehydomorpholine, keto-morpholine, morpholine or an aliphatic aromatic ketone. These preferred solvents have the advantage of providing a clear interface between the extract and raffinate in the extractor. Removal of the nonhydrocarbons permits production of more hydrocarbons having enhanced utility as a jet fuel from a synfuel liquid than otherwise would be possible.

Abstract: A process for the separation and recovery of substantially pure ammonia from its admixture with gases, particularly with gases containing carbon dioxide and gases obtained from the catalytic ammoxidation of hydrocarbons to the corresponding nitriles, by scrubbing the ammonia containing gases with an aqueous solution containing a mixture of salts having different cations and the anions of one or more inorganic acids capable of absorbing and liberating ammonia; e.g., mixtures of different alkali metal salts of phosphoric, telluric, boric, vanadic, chromic, selenic, germanic, silicic and similar acids. Preferably the anion component will be at least one of phosphoric, chromic, or boric acids.

Abstract: Oxygen compounds are removed, e.g., by solvent extraction, from a shale oil prior to its hydrogenation. As a result, the amount of hydrogen consumed during subsequent hydrogenation to achieve a given level of nitrogen for the shale oil is less than that which would occur if the oxygen compounds were not removed from the shale oil. Removal of the nitrogen is necessary to avoid adverse effects on subsequent shale oil processing steps such as catalytic cracking.

Abstract: In a cascade refrigeration system where low pressure vapor from an evaporator stage is compressed and then recycled for condensation to the evaporator of a previous stage, the improvement of passing the low pressure vapor from an evaporator stage through a heat exchanger to heat said vapor to ambient temperature, compressing said heated vapor, removing the compressor work by passing said compressed vapor through a cooler, cooling said compressed vapor by passing it through said heat exchanger in heat exchange relationship with said low pressure vapor, condensing it in the evaporator of the next higher temperature cycle of the cascade system and recycling the liquid to the low pressure evaporator stage.

Abstract: A process to separate hydrocarbon gases into different fractions by condensing in the high pressure condenser of a staged dual pressure rectification system only that amount of vapor necessary for the reboiler duty of the low pressure column and expanding the excess vapor to provide the low temperature refrigeration duty. The process of the invention lends itself particularly to refinery gases, particularly to an absorber tail gas which comprises a mixture of low molecular weight hydrocarbon gases (e.g. methane, ethane, ethylene, propane, etc.).