A sorbent composition that is useful for injection into a flue gas stream of a coal burning furnace to efficiently remove mercury from the flue gas stream. The sorbent composition may include a sorbent with an associated ancillary catalyst component that is a catalytic metal, a precursor to a catalytic metal, a catalytic metal compound or a precursor to a catalytic metal compound. Alternatively, a catalytic metal or metal compound, or their precursors, may be admixed with the coal feedstock prior to or during combustion in the furnace, or may be independently injected into a flue gas stream. A catalytic promoter may also be used to enhance the performance of the catalytic metal or metal compound.

In one aspect, systems and methods for the efficient and cost-effective removal of bromide from wastewater streams are described herein. Briefly, a system for bromide removal comprises pretreatment apparatus operable for at least partial removal of background ionic species from the wastewater stream and/or dilution of the background ionic species in the wastewater stream. The system also comprises bromide capture apparatus operable for removal of bromide from the pretreated wastewater stream, wherein the system removes bromide from the wastewater stream at an efficiency of at least 80 percent. In some embodiments, bromide is recovered from the capture apparatus and reused in flue gas treatment applications.

A gas separator includes a separation membrane complex in which a separation membrane with pores having a mean pore diameter less than or equal to 1 nm is formed on a porous support, and a gas supply part that supplies a mixed gas including CO.sub.2 and another gas from the side of the separation membrane to the separation membrane complex. Then, CO.sub.2 in the mixed gas is caused to permeate through the separation membrane and the support and is separated from the mixed gas in a state in which at least part of a permeation surface of the support, from which a gas having permeated through the separation membrane is exhausted, has a temperature lower by 10° C. or more than the temperature of the mixed gas before being supplied to the separation membrane complex.

A magnetic adsorbent, including an admixture of an adsorbent and a magnetic material. A system for removing mercury from a fluid stream, the system including, a magnetic adsorbent injection unit for injecting an admixture of powdered activated carbon and magnetic material into the fluid stream; and a particulate removal unit. Also included are methods for removing mercury from a fluid stream and methods for producing a magnetic sorbent.

A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

A graphene material coating and a preparation method thereof pertain to the technical field of air filtration, and relates to an air filtration device and system based on the graphene material coating. The preparation method of the graphene material coating includes the following steps: S1), preparing a slurry dispersion stock solution: adding a dispersant and a binder to a solvent, and stirring to form the slurry dispersion stock solution; and S2), forming a graphene surface coating: adding a graphene powder to the slurry dispersion stock solution, and after being homogenized by stirring, coating a homogenate on a surface of a carrier, and drying to obtain a finished product of the graphene material coating. This technique can increase the adsorption rate of harmful substances in the gases and avoid secondary pollution caused by unstable adsorption.

Provided herein a process for purification of an ionic liquid from heavy metals, comprising combining heavy metal-containing ionic liquid and a sulfide source to form heavy metal sulfide, and separating said heavy metal sulfide from the ionic liquid.

A process for producing a deacidified fluid stream from a fluid stream comprising methanol and at least one acid gas, comprising a) an absorption step in which the fluid stream is contacted with an absorbent in an absorber to obtain an absorbent laden with methanol and acid gases and an least partly deacidified fluid stream; b) a regeneration step in which at least a portion of the laden absorbent obtained from step a) is regenerated in a regenerator to obtain an at least partly regenerated absorbent and a gaseous stream comprising methanol and at least one acid gas; c) a recycling step in which at least a substream of the regenerated absorbent from step b) is recycled into the absorption step a); d) a condensation step in which a condensate comprising methanol is condensed out of the gaseous stream from step b);
wherein the regenerator additionally comprises a rescrubbing section, and the condensate from step d) is recycled into the regenerator partly in the upper region of the rescrubbing zone or above the rescrubbing zone.

Methods for the manufacture of sorbent compositions, sorbent compositions and methods for using the sorbent compositions. The methods include the utilization of an acidic halogen solution as a source of a halogen species that is dispersed on a solid sorbent. The use of the acidic halogen solution results in a highly active halogen species that demonstrates improved efficacy for the removal of heavy metal(s) from a flue gas. The sorbent composition includes a substantially amorphous halogen species associated with a solid sorbent such as powdered activated carbon (PAC).

A mercury sorbent and method for enhancing mercury removal performance of activated carbon from flue gas by the addition of non-halogen ammonium-containing compounds are provided herein.