The present invention relates to a method for purifying hydrogen peroxide, and more particularly, to a method including purifying a crude product of hydrogen peroxide using a primary purification system, and purifying a primarily purified hydrogen peroxide solution using a secondary purification system. One of the primary purification system and the secondary purification system includes an electrodeionization system, and the other one of the primary purification system and the secondary purification system includes at least one from among a distillation system, a resin system, a reverse osmosis system, and a combination system thereof.

A filtering device for obtaining a chemical liquid by purifying a liquid to be purified has an inlet portion, an outlet portion, a filter A, at least one filter B different from the filter A, and a flow path which includes the filter A and the filter B arranged in series between the inlet portion and the outlet portion and extends from the inlet portion to the outlet portion, in which the filter A has a porous base material made of polyfluorocarbon and a coating layer which is disposed to cover the porous base material and contains a first resin having a hydrophilic group.

Selective removal of non-aromatic hydrocarbons from a xylene isomerization process for para-xylene production is accomplished using a membrane unit positioned within a xylene recovery loop. The membrane unit may include a one-stage or multi-stage (e.g., two-stage) membrane system and may be configured to separate a membrane unit product stream from a non-aromatics rich stream, which can be removed from the xylene recovery loop. The membrane unit may have a xylene permeance of about 60 gm/m2/hr/psi and a xylene to non-aromatic permeance ratio of about 15.

Producing a dealcoholized beverage from its alcoholic beverage starting product and plant for implementing the method, which comprises the following steps: separating the beverage starting product into an alcoholic and aromatic permeate and into an aromatic and almost alcohol-free retentate in a permeation module by non-thermal permeation, dealcoholizing the permeate in a module intended for that task, and finally mixing the dealcoholized permeate with the almost alcohol-free retentate in a final-mixing module. Prior to the dealcoholizing, aroma compounds are removed from the aromatic and alcoholic permeate by cold adsorption in an aroma adsorber, resulting both in an aroma phase and in an aroma-free but alcoholic permeate which, however, has the alcohol removed from it by alcohol separation, resulting in an aqueous, largely dearomatized and dealcoholized permeate water phase. Final mixing of aroma phase, permeate water phase and retentate takes place in the final-mixing module to give a dealcoholized beverage.

In the method for decolorizing a vegetable wax, a vegetable wax raw material dissolved in an organic solvent is contacted under pressure with a nanofiltration membrane having a higher rejection for a pigment, contained in the vegetable wax raw material, than for the wax components, providing a permeate containing decolorized wax and enriching the pigment in the retentate.

A filtration system includes at least one spiral wound first filter section in fluid communication with at least one spiral wound second filter section. The first and second filter sections include: (i) a filtration membrane; (ii) a feed spacer located adjacent the filtration membrane and defining a feed flow channel; and (iii) a permeate spacer located adjacent the filtration membrane and defining a permeate flow channel. A thickness of the feed flow channel in the first filter section is different than a thickness of the feed flow channel in the second filter section, and/or an effective volume of the first filter section is different than an effective volume of the second filter section. A method of filtering a feed flow is also disclosed.

A method for treating produced water in a system for treating wastewater is disclosed. The system includes a reverse osmosis unit for removing dissolved solids. The reverse osmosis unit produces a permeate and concentrate. To reduce the fouling potential of the membranes associated with the reverse osmosis unit and/or to increase membrane lifetime and/or to increase system recovery, at least a portion of the concentrate is recycled and mixed with the wastewater stream at a point upstream of the reverse osmosis unit.

The present invention relates to an olefins-paraffins separation process in feed stream containing hydrocarbons with 2 to 4 carbon atoms by facilitated transport membrane specific to olefins, comprising the following step: a. feeding the feed stream containing hydrocarbons with 2 to 4 carbon atoms into distillation column and at least 1 stage of membrane unit connected to distillation column at the feed of distillation column and at least 1 stage of membrane unit connected to the side draw of distillation column; and b. separating a portion of feed stream that is passed from the membrane unit, at least 1 stream is the product stream that mostly comprising olefins and at least 1 stream that mostly comprising paraffins.

The present invention provides a gas separation system suitable for reducing energy required to separate a gas mixture. A gas separation system of the present invention includes: a first separation membrane unit that separates a gas mixture containing carbon dioxide and nitrogen into a first permeated gas and a first non-permeated gas; a second separation membrane unit that separates the first permeated gas into a second permeated gas and a second non-permeated gas; a first decompression device that decompresses a permeation-side space of the first separation membrane unit; and a second decompression device that decompresses a permeation-side space of the second separation membrane unit.

The present invention relates to a method for the production of drinking water. In addition, the present invention also relates to the use of minerals extracted from a feed water stream by using a combination of a Donnan dialysis unit and a membrane unit as a source of minerals for the production of drinking water originating from said feed water stream.