The invention relates to a method for increasing the absorbency of a material containing alkaline-earth carbonate and alkaline-earth hydroxide with regard to sulfur oxides and/or other pollutants, in particular in flue gas, wherein the material containing alkaline-earth carbonate and alkaline-earth hydroxide is activated by heating said material to approximately 250 C. to approximately 750 C. for a time period of 1 minute to 12 hours.

A gas supply system may include a first gas supply line, a second gas supply line, a circulation gas pipe, a gas purification unit, a first valve, and a second valve. The first gas supply line may include a first branching point at which the first gas supply line branches into a first branch connected to a first chamber and a second branch connected to a second chamber and the second gas supply line may include a second branching point at which the second gas supply line branches into a third branch connected to the first chamber and a fourth branch connected to the second chamber. A first portion of the first gas supply line upstream from the first branching point and a second portion of the second gas supply line upstream from the second branching point may be constituted by separate pipes from each other.

An apparatus and method for purifying a raw hydrogen gas stream of chloramines and chlorine is provided. The explosive chloramines compounds can be effectively captured by the carbon adsorbent without accumulating on the carbon surface. Rather, the chloramines are converted via decomposition, into non-explosive products with catalytic effect of the carbon material. Chlorine reacts with impregnated reducing agent on the carbon surface to form the solid products, which can be adsorbed on the carbon surface. The purified hydrogen gas contains little to no trace of chloramines and chlorine impurities, thereby making the hydrogen gas suitable for liquid hydrogen production.

A hydrated lime product exhibiting superior reactivity towards HCl and SO.sub.2 in air pollution control applications. Also disclosed is a method of providing highly reactive hydrated lime and the resultant lime hydrate where an initial lime feed comprising calcium and impurities is first ground to a particle-size distribution with relatively course particles. Smaller particles are then removed from this ground lime and the smaller particles are hydrated and flash dried to form a hydrated lime, which is then milled to a significantly smaller particle size than that of the relatively course particles. The resultant lime hydrate product has available CaOH of greater than 92%, a citric acid reactivity of less than 20 seconds, a BET surface area greater than 18, a D90 less than 10 m, a D50 less than 4 m, a D90/D50 less than 3, and a large pore volume of greater than 0.2 BJH.

The invention relates to a method for cleaning flue gas, the flue gas to be cleaned and a sorption agent starting material in the form of a solid being injected into a reactor chamber of a fluidized-bed reactor, and a liquid being injected into the reactor chamber separately from the flue gas and the sorption agent starting material, the sorption agent starting material being contacted with the liquid in the fluidized-bed reactor and being converted to a sorption agent in the form of a solid.

Calcium hydroxide-containing compositions can be manufactured by slaking quicklime, and subsequently drying and milling the slaked product. The resulting calcium hydroxide-containing composition can have a size, steepness, pore volume, and/or other features that render the compositions suitable for treatment of exhaust gases and/or removal of contaminants. In some embodiments, the calcium hydroxide-containing compositions can include a D.sub.10 from about 0.5 microns to about 4 microns, a D.sub.90 less than about 30 microns, and a ratio of D.sub.90 to D.sub.10 from about 8 to about 20, wherein individual particles include a surface area greater than or equal to about 25 m.sup.2/g.

The present invention relates to a fluorine-containing gas removing agent comprising an alumina and an alkali earth metal compound, wherein an ammonia desorption curve obtained by an ammonia TPD-MS method having a mass-to-charge ratio of 15 has a peak in a range lower than 200 C. and has a shoulder in a range of 200 C. or higher.

Process for preparing a catalyst or a trapping mass comprising the following steps: bringing a porous oxide support into contact with a metal salt comprising at least one metal belonging to groups VIB, VIIB, VIIIB, IB or IIB, of which the melting point of said metal salt is between 20 C. and 150 C., for a period of between 5 minutes and 5 hours in order to form a solid mixture, the weight ratio of said metal salt to said porous oxide support being between 0.1 and 1; heating the solid mixture with stirring at a temperature between the melting point of said metal salt and 200 C. and for 5 minutes to 12 hours; calcining the solid obtained in the preceding step at a temperature above 200 C. and below or equal to 1100 C. under an inert atmosphere or under an oxygen-containing atmosphere.

Disclosed is a process for treating a gas stream containing hydrochloric acid, hydrofluoric acid, a fluorinated compound and halogenated organic compounds, wherein the gas stream is subjected to: (a) a step of washing with an acid solution to obtain a washed gas stream; (b) a step of adiabatic absorption in an aqueous solution of the hydrochloric acid contained in said washed gas stream, to collect a solution of hydrochloric acid; (c) a step of adsorption on activated carbon of the impurities present in said hydrochloric acid solution, to obtain a purified hydrochloric acid solution and a gas stream containing said fluorinated compound; and (d) a step of bringing said purified hydrochloric acid solution into contact with a silica gel. Also disclosed is a plant for the implementation of this process, and also a process for preparing a fluorinated compound comprising the catalytic pyrolysis of an organofluorine compound.

A hydrated lime product exhibiting superior reactivity towards HCl and SO.sub.2 in air pollution control applications. Also disclosed is a method of providing highly reactive hydrated lime and the resultant lime hydrate where an initial lime feed comprising calcium and impurities is first ground to a particle-size distribution with relatively course particles. Smaller particles are then removed from this ground lime and the smaller particles are hydrated and flash dried to form a hydrated lime, which is then milled to a significantly smaller particle size than that of the relatively course particles. The resultant lime hydrate product has available CaOH of greater than 92%, a citric acid reactivity of less than 20 seconds, a BET surface area greater than 18, a D90 less than 10 m, a D50 less than 4 m, a D90/D50 less than 3, and a large pore volume of greater than 0.2 BJH.