The present invention provides processes for filtering undesired chemicals in streams of contaminated air for supply to confined areas. The processes provide (1) contacting air with a filter comprising by volume from about 5% to about 95% impregnated zirconium hydroxide, from about 5% to about 95% activated impregnated carbon, and optionally, up to about 50% ammonia removal material; and (2) supplying the contacted air to a confined area.

The present invention provides a new carbon dioxide fixation apparatus. The carbon dioxide fixation apparatus (1) of the present invention includes: a first reaction vessel (10); a carbon dioxide fixing agent feeding unit (110); and a gas-liquid mixing unit. The first reaction vessel (10) can contain a carbon dioxide fixing agent, the carbon dioxide fixing agent feeding unit (110) can feed the carbon dioxide fixing agent into the first reaction vessel (10), and the gas-liquid mixing unit can mix a gas containing carbon dioxide into the carbon dioxide fixing agent.

Disclosed are methods and systems for removing submicron particles from a gas stream, in particular from urea prilling off-gas, wherein a Venturi ejector is used. A method comprises contacting a gas stream containing submicron particles in a Venturi ejector with an injected high velocity scrubbing liquid to provide a pumping action, wherein the scrubbing liquid has an initial velocity of at least 25 m/s and wherein the ratio of scrubbing liquid and gas flow is between 0.0005 and 0.0015 (m.sup.3/h)/(m.sup.3/h).

The present disclosure relates to methods for producing metal sulfide disposed on particle substrates. In at least one embodiment, a method for producing an alkali earth hydroxide particle having a metal sulfide disposed thereon includes introducing an alkali earth oxide particle with a metal sulfate to form a first composition. The method includes introducing an alkali sulfide or an alkali earth sulfide with the first composition to form a second composition. The present disclosure further relates to compositions of matter having metal sulfide disposed on a particle substrate. In at least one embodiment, a composition of matter includes an alkali earth hydroxide particle. The composition of matter includes a metal sulfide disposed on the alkali earth hydroxide particle.

A process for the conversion of solid lignocellulosic material containing hemicellulose, cellulose and lignin, includes (a) hydrolyzing, at a temperature equal to or less than 40° C. at least part of the hemicellulose and at least part of the cellulose of the solid lignocellulosic material with an aqueous hydrochloric acid solution, containing in the range from equal to or more than 40.0 wt. % to equal to or less than 51.0 wt. % hydrochloric acid, based on the combined weight amount of water and hydrochloric acid in the aqueous hydrochloric acid solution; yielding a hydrochloric acid-containing, aqueous hydrolysate solution; (b) separating the hydrochloric acid-containing, aqueous hydrolysate solution from the lignin; and (c) heating at least part of the hydrochloric acid-containing, aqueous hydrolysate solution to a temperature equal to or more than 60° C., yielding a product solution containing 5-(chloromethyl)furfural, and extracting the 5-(chloromethyl)furfural from the product solution into an extraction solvent.

A method of treating a metal carbonate salt includes hydrolyzing a metal halide salt to form a hydrohalic acid and a hydroxide salt of the metal in the metal halide salt. The metal includes an alkaline earth metal or an alkali metal. The method includes reacting the hydrohalic acid with the metal carbonate salt, wherein the metal carbonate salt is a carbonate salt of the alkaline earth metal or alkali metal, to form CO.sub.2 and the metal halide salt. At least some of the metal halide salt formed from the reacting of the hydrohalic acid with the metal carbonate salt is recycled as at least some of the metal halide salt in the hydrolyzing of the metal halide salt to form the hydrohalic acid and the hydroxide salt.

A plasma abatement process for abating effluent containing compounds from a processing chamber is described. A plasma abatement process takes gaseous foreline effluent from a processing chamber, such as a deposition chamber, and reacts the effluent within a plasma chamber placed in the foreline path. The plasma dissociates the compounds within the effluent, converting the effluent into more benign compounds. Abating reagents may assist in the abating of the compounds. The abatement process may be a volatizing or a condensing abatement process. Representative volatilizing abating reagents include, for example, CH.sub.4, H.sub.2O, H.sub.2, NF.sub.3, SF.sub.6, F.sub.2, HCl, HF, Cl.sub.2, and HBr. Representative condensing abating reagents include, for example, H.sub.2, H.sub.2O, O.sub.2, N.sub.2, O.sub.3, CO, CO.sub.2, NH.sub.3, N.sub.2O, CH.sub.4, and combinations thereof.

The present disclosure provides systems and methods useful in capture of one more moieties (e.g., carbon dioxide) from a gas stream (i.e., direct air capture). In various embodiments, the systems and methods can utilize at least a scrubbing unit, a regeneration unit, and an electrolysis unit whereby an alkali solution can be used to strip the moiety (e.g., carbon dioxide) from the gas stream, the removed moiety can be regenerated and optionally purified for capture or other use, and a formed salt can be subjected to electrolysis to recycle the alkali solution back to the scrubber for re-use with simultaneous production of one or more further chemicals.

The present invention can provide a new method for fixing carbon dioxide. The method for fixing carbon dioxide of the present invention includes a contact step of bringing a mixed liquid containing sodium hydroxide and further containing at least one of a chloride of a Group 2 element or a chloride of a divalent metal element into contact with a gas containing carbon dioxide, wherein in the contact step, the mixed liquid and the gas are brought into contact with each other by feeding the gas into the mixed liquid.

A process and device for enhancing the chemical protection capability of a collective protection filter whereby the process stream exiting the collective protection filter is passed through an Auxiliary Filter. The auxiliary filter containing an ammonia removal media, such as zirconium hydroxide impregnated with zinc chloride (ZnCl.sub.2/Zr(OH).sub.4), an oxidizing media, preferably zirconium hydroxide impregnated with potassium permanganate (KMnO.sub.4/Zr(OH).sub.4), and a methyl bromide removal media, preferably activated carbon impregnated with triethylenediamine (TEDA/carbon). The auxiliary filter and process are configured to remove toxic industrial chemicals including NH.sub.3, NO.sub.x (mixtures of NO and NO.sub.2) and CH.sub.2O, and CH.sub.3Br.