Provided herein are molecular sieve membranes for separating hydrocarbons of a lube feed stock into a permeate and a retentate based on molecular shape. The molecular sieve membranes comprise one or more layers of size-selective catalyst and a porous support comprising a plurality of diffusing gaps. Each layer of size-selective catalyst has a plurality of perpendicular membrane channels and a plurality of opening pores. The porous support is in fluidic communication with the plurality of opening pores to provide a fluidic pathway between the perpendicular membrane channels and the diffusing gaps. Also provided are processes for separating n-paraffins from other hydrocarbons in a lube feed stock using the present molecular sieve membranes.

A process for reducing injector deposits in an internal combustion engine fuelled with a fuel composition, the process comprising contacting a fuel composition with a metal-selective membrane situated in the fuel delivery system. The reduction of such deposits provides an increase in fuel efficiency, fuel thermal stability, boost in engine cleanliness, improves fuel economy and enables the possibility of using a reduced amount of expensive detergent in the fuel composition.

A process for reducing injector deposits in an internal combustion engine fuelled with a fuel composition, the process comprising contacting a fuel composition with a metal-selective membrane situated in the fuel delivery system. The reduction of such deposits provides an increase in fuel efficiency, fuel thermal stability, boost in engine cleanliness, improves fuel economy and enables the possibility of using a reduced amount of expensive detergent in the fuel composition.

In an embodiment is provided a process to re-refine used oil that includes introducing a used oil and a solvent to a separation unit under separation conditions selected to produce a purified oil product, the separation unit comprising a porous membrane, a semiporous membrane, or both; and separating the used oil to obtain an effluent comprising a purified oil product. In another embodiment is provided an apparatus for re-refining used oil that includes a separation unit comprising a porous or semiporous membrane; a used oil feed coupled to an inlet of the separation unit; and an inlet of a diffusate collection unit coupled to an outlet of the separation unit. In another embodiment is provided a composition generated from a membrane separation process that includes a base oil, the composition having a soot content of about 0.05% or less.

A process for preparing a base oil fraction having a reduced cloud point from a hydrocarbon feed which is derived from a Fischer-Tropsch process is provided. The process comprises: subjecting a hydrocarbon feed which is derived from a Fischer-Tropsch process to a catalytic dewaxing treatment to obtain an at least partially isomerised product; separating at least part of the at least partially isomerised product into one or more light hydrocarbon fractions and one or more heavy base oil fractions; separating at least one of the heavy base oil fractions by means of a first membrane into a first permeate and a first retentate; separating at least part of the first permeate by means of a second membrane into a second permeate and a second retentate; and recovering the second permeate.

A method for preparing needle coke for ultra-high power (UHP) electrodes from heavy oil is provided. In this method, heavy oil is used as a raw material. The size exclusion chromatography (SEC) is conducted with polystyrene (PS) as a packing material to separate out specific components with a relative molecular weight of 400 to 1,000. The ion-exchange chromatography (IEC) is conducted to remove acidic and alkaline components to obtain a neutral raw material. The neutral raw material is subjected to two-stage consecutive carbonization to obtain green coke, and the green coke is subjected to high-temperature calcination to obtain the needle coke for UHP electrodes. The needle coke has a true density of more than 2.13 g/cm.sup.3 and a coefficient of thermal expansion (CTE) of ≤1.15×10.sup.−6/° C. at 25° C. to 600° C.

The invention relates to the oil-refining industry, in particular, to methods for purifying a fuel from sulfur-containing compounds, by separating the sulfur-containing modified molecules from the remainder of the fuel molecules on polymer membranes and by activating the fuel purified in the fully-developed cavitation mode prior to the combustion. The reduction of the sulfur content in the fuel is achieved by treating the fuel or a fuel fraction in the fully-developed cavitation mode with addition of a hydrogen peroxide aqueous solution and/or a strong aqueous solution of iron oxides, followed by separating the obtained emulsion into a fuel fraction and a water-paraffin emulsion, followed by separating the fuel fraction on the membranes under the temperature of from 90° C. to 180° C. under atmospheric pressure into a fuel fraction having low sulfur combustion of the purified fuels down to zero by means of activation of the fuels having the low sulfur content.

A membrane separator comprising a membrane is used to separate various streams in processes for separating aromatic hydrocarbons from non-aromatic hydrocarbons. Such streams can be a lean-solvent stream, a rich-solvent stream, or a hydrocarbon stream comprising both aromatic and non- aromatic hydrocarbons. The membrane separator is advantageously used in combination with an extraction sub-system including a liquid—liquid distillation column and/or an extraction distillation column.

A liquid fuel synthesis system includes a liquid fuel synthesis portion and a sweep gas supply unit. The liquid fuel synthesis portion is partitioned into a non-permeation side space and a permeation side space by the separation membrane. A temperature of the sweep gas flowing into the permeation side space is higher than at least one of a temperature of the raw material gas flowing into the non-permeation side space and a temperature of a first outflow gas flowing out of the non-permeation side space. A temperature of a second outflow gas flowing out of the permeation side space is higher than at least one of the temperature of the raw material gas flowing into the non-permeation side space and the temperature of the first outflow gas flowing out of the non-permeation side space.

A method for preparing needle coke for ultra-high power (UHP) electrodes from heavy oil is provided. In this method, heavy oil is used as a raw material. The size exclusion chromatography (SEC) is conducted with polystyrene (PS) as a packing material to separate out specific components with a relative molecular weight of 400 to 1,000. The ion-exchange chromatography (IEC) is conducted to remove acidic and alkaline components to obtain a neutral raw material. The neutral raw material is subjected to two-stage consecutive carbonization to obtain green coke, and the green coke is subjected to high-temperature calcination to obtain the needle coke for UHP electrodes. The needle coke has a true density of more than 2.13 g/cm.sup.3 and a coefficient of thermal expansion (CTE) of ≤1.15×10.sup.−6/° C. at 25° C. to 600° C.