A process for the separation of a natural gas stream is provided. The process includes receiving an effluent gas flow from a first fractionator operating at a first pressure, splitting the effluent gas flow into a first stream and a second stream, and passing the first stream through a heat exchanger thereby causing a phase change of at least a portion of the first stream from a gaseous state to a liquid state. The process includes inserting the first stream into an upper portion of a second fractionator operating at a second pressure. The second pressure is lower than the first pressure. The process includes inserting the second stream into a lower portion of the second fractionator, and diverting liquids from a lower portion of the second fractionator to the first fractionator.

The invention relates to a method for producing polyisocyanates having a low monomer content, said method comprising the following steps: (i) modifying at least one monomeric diisocyanate to obtain a mixture containing at least one polyisocyanate and unconverted monomeric diisocyanate, (ii) separating the mixture obtained in step (i) into at least one gaseous stream containing monomeric diisocyanate and a liquid stream depleted of monomeric diisocyanate, (iii) partially condensing the gaseous stream from (ii) in at least one condenser, so that a liquid condensate and an uncondensed vapour stream are obtained, (iv) post-condensing the uncondensed vapour stream obtained in step (iii) in at least one post-condenser, so that a post-condensate and an uncondensed waste gas are obtained, and (v) delivering the uncondensed waste gas from step (iv) to the suction side of a vacuum pump, characterised in that the at least one post-condenser in step (iv) is operated at a post-condenser temperature, and the at least one condenser in step (iii) is operated at a condenser temperature, wherein the post-condenser temperature is lower by ≥1 to ≤168 K than the condenser temperature.

A process for the treatment of a gasoline containing sulfur compounds and olefins includes the following stages: a) hydrodesulfurization in the presence of a catalyst having an oxide support and an active phase having a metal from group VIB and a metal from group VIII, b) hydrodesulfurization at a higher temperature than that of stage a) and in the presence of a catalyst having an oxide support and an active phase with at least one metal from group VIII, c) separation of H.sub.2S formed, d) hydrodesulfurization at a low hydrogen/feedstock ratio and in the presence of a hydrodesulfurization catalyst having an oxide support and an active phase having a metal from group VIB and a metal from group VIII or an active phase with at least one metal from group VIII, and e) further separation of H.sub.2S formed.

The process can include transferring heat from a light product in a first heat exchange stage to produce a cooled product and a first medium pressure steam and separating a steam cracker quench oil therefrom. Heat can be transferred from the steam cracker quench oil in a second heat exchange stage to produce a first cooled quench oil and a second medium pressure steam. Heat can be transferred from at least a portion of the first cooled quench oil in a third heat exchange stage to produce a second cooled quench oil and low pressure steam. A total heat duty generated in the first heat exchange stage, the second heat exchange stage, and the third heat exchange stage can be equal to Q.sub.T1 and a heat duty generated in the first heat exchange stage and the second heat exchange stage can be ≥0.5Q.sub.T1 joules/sec.

This invention provides a method for stably producing 2,3,3,3-tetrafluoropropene for a long period of time wherein unreacted materials are reused after distillation without liquid-liquid separation to suppress catalyst deactivation. The method for producing 2,3,3,3-tetrafluoropropene comprises the step of reacting 1233xf or like chloropropene with hydrogen fluoride in the presence of a catalyst, the step of subjecting the reaction mixture obtained in the above step to distillation to separate the mixture into a first stream comprising 2,3,3,3-tetrafluoropropene as a main component and a second stream comprising unreacted hydrogen fluoride and organic matter containing unreacted chloropropene as main components, and the step of recycling the second stream to the above reaction, the distillation being performed under conditions in which the unreacted hydrogen fluoride and the organic matter containing the unreacted chloropropene do not undergo liquid-liquid separation at a portion of a distillation column from which the second stream is withdrawn.

Provided is a method of recovering unreacted ethylene in an ethylene oligomerization process and reusing the ethylene as a raw material, and more particularly, to a method of recovering unreacted ethylene with an increased recovery rate of reuse. When the method of the present invention is used, most of unreacted ethylene may be dissolved in a solvent to be recovered without loss, and a low boiling point reaction product which is not dissolved in the solvent is removed to prevent an unreacted product from being concentrated in a reactor.

A method of extracting nutrients from a plant includes the steps of: pulverizing a water soluble nutrient-based plant part of a first plant material of the plant so as to form a first pulverized plant part; pulverizing a lipid soluble nutrient-based plant part of a second plant material of the plant so as to form a second pulverized plant part; subjecting the first pulverized plant part to a distillation so as to obtain a distillate and a first residue that contains a water soluble nutrient; and immersing the second pulverized plant part in the distillate to form a first mixture followed by distillation of the first mixture, so as to obtain a second residue that contains a lipid soluble nutrient.

The present invention pertains to a process for refining of crude tall oil (CTO). The process comprises fractionation under vacuum of a refined CTO into at least one stream of refined tall diesel (RTD) or tall oil fatty acids (TOFA), the RTD or TOFA comprises from 2-30% by volume of resin acids and from 20-90% by volume of fatty acids, and at least one stream of resin acid(s) (RA) comprising less than 5% by volume of fatty acids. The stream of RTD or TOFA is deoxygenated forming hydrocarbon compounds in a subsequent step. This invention also relates to a refined tall diesel. Furthermore, a process for the production of a refined tall diesel (RTD) composition, wherein crude sulphate turpentine(s) (CST) is added to the refined tall diesel (RTD) composition, is described.

By incorporating an additional TCS and/or DCS redistribution reactor in the TCS recycle loop and/or DCS recycle loop, respectively, of a process and system for silane manufacture, efficiencies in the production of silane are realized.

This disclosure relates to a method of continuous recovery of (meth)acrylic acid and an apparatus used for the recovery method. The method of continuous recovery of (meth)acrylic acid according to the present invention may effectively remove scum formed in the continuous recovery process of (meth)acrylic acid, and simultaneously recover (meth)acrylic acid with excellent efficiency, thus enabling more stable operation of the continuous process.