In the present disclosure there is provided a process for obtaining di-sulfide oil having sodium level below 0.1 ppm wherein a stream comprising di-sulfide oil having sodium level 1 ppm, collected as a waste stream from LPG desulfurization unit, is passed through an alumina bed packed in a column at a pre-determined liquid hourly space velocity (LHSV) and at pre-determined temperature to obtain a treated stream comprising di-sulfide oil having sodium level below 0.1 ppm.

In the present disclosure there is provided a process for obtaining di-sulfide oil having sodium level below 0.1 ppm wherein a stream comprising di-sulfide oil having sodium level 1 ppm, collected as a waste stream from LPG desulfurization unit, is passed through an alumina bed packed in a column at a pre-determined liquid hourly space velocity (LHSV) and at pre-determined temperature to obtain a treated stream comprising di-sulfide oil having sodium level below 0.1 ppm.

The present invention discloses high pressure flow reactor vessels and associated systems. Also disclosed are processes for producing thiol compounds and sulfide compounds utilizing these flow reactor vessels.

The present invention discloses high pressure flow reactor vessels and associated systems. Also disclosed are processes for producing thiol compounds and sulfide compounds utilizing these flow reactor vessels.

The present disclosure in part provides compounds (i.e., PEG lipids) which are useful in pharmaceutical compositions, cosmetic compositions, and drug delivery systems, e.g, for use in lipid nanoparticle (LNP) formulations. The present disclosure also provides LNP formulations comprising PEG lipids described herein, and methods of using the same. For example, the LNPs provided herein are useful for the delivery of an agent (e.g, therapeutic agent) to a subject. The PEG lipids and LNPs provided herein, in certain embodiments, exhibit increased PEG shedding compared to existing PEG lipids and LNP formulations.

The present disclosure in part provides compounds (i.e., PEG lipids) which are useful in pharmaceutical compositions, cosmetic compositions, and drug delivery systems, e.g, for use in lipid nanoparticle (LNP) formulations. The present disclosure also provides LNP formulations comprising PEG lipids described herein, and methods of using the same. For example, the LNPs provided herein are useful for the delivery of an agent (e.g, therapeutic agent) to a subject. The PEG lipids and LNPs provided herein, in certain embodiments, exhibit increased PEG shedding compared to existing PEG lipids and LNP formulations.

A polythiol composition according to the present invention includes a polythiol compound (A) having three or more mercapto groups and a nitrogen-containing compound (B) in which one of a mercapto group of the polythiol compound (A) is replaced with a group represented by the following formula (a) and other one of a mercapto group of the polythiol compound (A) is replaced with a hydroxyl group, in which the peak area of the nitrogen-containing compound (B) is equal to or less than 3.0 with respect to the peak area of 100 of the polythiol compound (A) in a high performance liquid chromatography measurement. ##STR00001##

A polythiol composition according to the present invention includes a polythiol compound (A) having three or more mercapto groups and a nitrogen-containing compound (B) in which one of a mercapto group of the polythiol compound (A) is replaced with a group represented by the following formula (a) and other one of a mercapto group of the polythiol compound (A) is replaced with a hydroxyl group, in which the peak area of the nitrogen-containing compound (B) is equal to or less than 3.0 with respect to the peak area of 100 of the polythiol compound (A) in a high performance liquid chromatography measurement. ##STR00001##

A method for producing methionine involves contacting 2-amino-4-(methylthio)butanenitrile with water in the presence of an oxide catalyst containing cerium. The 2-amino-4-(methylthio)butanenitrile may be 2-amino-4-(methylthio)butanenitrile, produced by contacting 2-hydroxy-4-(methylthio)butanenitrile with ammonia water or 2-amino-4-(methylthio)butanenitrile, produced by contacting 3-(methylthio)propionaldehyde with hydrocyanic acid and ammonia water.

The present invention provides a polythiol composition containing, as the main component, a polythiol compound (a) having two or more mercapto groups, and containing 0.5% by mass or less of a nitrogen-containing compound (b) in which at least one mercapto group in the polythiol compound (a) is substituted with a group represented by formula (1).

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