The present disclosure relates to methods of synthesizing slurries comprising ferrihydrite nanoparticles, and systems and methods employing the same. The method may include the steps of preparing an aqueous solution having ferric iron cations, halide anions, and a two-line iron promoter, and precipitating the ferrihydrite nanoparticles in the aqueous solution, thereby producing a ferrihydrite slurry. The ferrihydrite slurries may be useful in treating a polluted fluid having sulfur contaminants therein.

Disclosed is a process for the regeneration of an adsorber (A1). The adsorber (A1) is regenerated by contact with a gaseous stream (S2) and the outflow of the adsorber (A1) comprising condensate of stream (S2) and organic composition (OC1) collected in a device. After regeneration of the adsorber (A1) the stream (S2) in the adsorber (A1) is replaced completely or at least partially by the content of the device. Then the adsorber (A1) is fed with organic composition comprising at least one olefin, at least one alkane and at least one compound containing oxygen and/or sulfur.

Disclosed is a process for the regeneration of an adsorber. For the regeneration a liquid stream (S2) is applied which is obtained by hydrogenation of a stream (S1) comprising at least one alkane and least one olefin. The stream (S2) comprises one alkane and a reduced amount of at least one olefin compared to the amount in the stream (S1). Then the stream (S2) is converted from the liquid into the gaseous phase and the adsorber is regenerated by contact with the gaseous stream (S2).

Disclosed is an improved process for recovering condensable components from a gas stream, in particular, hydrocarbons from a gas stream such as natural gas. The present process uses solid adsorbent media to remove said hydrocarbons wherein the adsorbent media is regenerated in a continuous fashion in a heated continuous counter-current regeneration system, wherein said heated regenerated adsorbent media is cooled prior to reuse.

Disclosed are embodiments of a method of regenerating a desiccant in an off-line treater of a polyolefin production process. The method may include a heating phase followed by a cooling phase. The heating phase may involve use of a regenerating gas made from heating a treated a recycle stream of the polyolefin production process to regenerate desiccant in an off-line treater. The cooling phase may involve thermosyphoning the regenerating gas, nitrogen, an olefin-free diluent, or combinations thereof in a closed-convection loop of the off-line treater.

Provided is a method for reusing an adsorbent which can stably exhibit purification ability by regenerating a used absorbent, in order to keep the composition of a purified syngas constant.

The present invention concerns a method for regenerating a zeolite adsorbent which adsorbs a carbon dioxide gas from a syngas comprising the carbon dioxide gas and reduces the concentration of the carbon dioxide gas in the syngas, comprising: a step of recovering a used zeolite adsorbent; a step of calcining the used zeolite adsorbent at a temperature of 300° C. to 600° C. in an oxygen atmosphere to produce a regenerated zeolite adsorbent; and a step of reusing the regenerated zeolite adsorbent.

The invention relates to a process for regeneration of an adsorber (A) by contact with a stream (S1), wherein the stream (S1) is heated in advance by at least two heat exchange units (HEU1) and (HEU2). As outflow of the adsorber (A) a stream (S2) is obtained, which is passed through at least two heat exchange units (HEU1) and (HEU2) traversed by stream (S1), wherein the temperature of stream (S2) fed into each heat exchange unit is higher than the temperature of stream (S1) fed into the heat exchange units (HEU1) and (HEU2), in order to directly transfer heat from stream (S2) to stream (S1).

An ammonia chemical species desorption process desorbs ammonia chemical species adsorbed onto a Prussian blue derivative more simply at lower cost under milder conditions as compared with using an aqueous solution of a salt or strong acid, and only water. This ammonia chemical species desorption process includes an ammonia chemical desorption step of bringing carbon dioxide and water into contact with a Prussian blue derivative represented by the following general formula (1), thereby desorbing an ammonia chemical species.

A.sub.xM[M′(CN).sub.6].sub.y.zH.sub.2O  (1)

where x is 0 to 3, y is 0.1 to 1.5, z is 0 to 6, A is at least one cation of hydrogen, ammonium, an alkaline metal, and an alkaline earth metal, and M and M′ are each independently at least one cation of at least one of atoms having atomic numbers 3 to 83 except for ammonium, an alkali metal, and an alkaline earth metal.

A hydrocarbon removal system according an embodiment of the present invention includes: a first area including a first hydrocarbon adsorption catalyst having a first pore size; and a second area including a second hydrocarbon adsorption catalyst having a second pore size, wherein the first pore size may be smaller than the second pore size, the first hydrocarbon adsorption catalyst may include CHA zeolite, and the second hydrocarbon adsorption catalyst may include ZSM-5 zeolite.

Methods for desorbing volatile organic compounds (VOCs) from beaded activated carbon (BAC) that is loaded with VOCs, during the VOC abatement process using the fluidized carbon bead system include transferring the loaded BAC in an adsorber to a desorber, where a stream of organic solvent passes over the BAC to dissolve at least a portion of the adsorbed VOCs into the organic solvent to regenerate BAC. The regenerated BAC is returned to the adsorber. The organic solvent containing dissolved VOCs may be transferred to a distiller to separate the organic solvents from the dissolved VOCs and may be reused as the organic solvent in the desorber.