The present description relates to a process for producing magnesium metal from dihydrate magnesium chloride comprising the steps of dehydrating MgCI.sub.2.2H.sub.2O with anhydrous hydrochloric acid (HCI) to obtain anhydrous magnesium chloride in an inert environment, releasing the mixture of hydrous HCI and protection gas; and electrolyzing the anhydrous magnesium chloride in an electrolytic cell fed with hydrogen gas under free oxygen atmosphere content, wherein magnesium metal and anhydrous hydrogen chloride are produced, wherein a part of the hydrous HCI is passed through a scrubbing unit to obtain a hydrochloric acid solution, the other part of the hydrochloric chloride gas is dehydrated by contact with a desiccant agent in a drying unit to produce anhydrous HCI, and wherein the anhydrous HCI produced by at least one of the electrolytic cell and the drying unit is reused to dehydrate the of MgCI.sub.2.2H.sub.2O.

An abatement apparatus capable of treating exhaust gas with less wet treatment devices than a conventional abatement apparatus is disclosed. The abatement apparatus includes: a pre-wet treatment device; a combustion treatment device; gas introduction lines coupled to process chambers of a film forming device; first flow-path switching devices coupled to the plurality of gas it lines, respectively; a first gas delivery line extending from the first flow-path switching devices to the pre-wet treatment device; a second gas delivery line extending from the first flow-path switching devices to the combustion treatment device; and an operation controller configured to control operations of the first flow-path switching devices to deliver the process gas to the pre-wet treatment device and deliver the cleaning gas to the combustion treatment device.

The invention relates to a method for treating emergency spill or leak of halogen which is bromine or chlorine, comprising contacting an aqueous solution of quaternary ammonium halide with the halogen.

The invention relates to a method for treating emergency spill or leak of halogen which is bromine or chlorine, comprising contacting an aqueous solution of quaternary ammonium halide with the halogen.

Novel methods for pretreating a rare-gas-containing stream exiting an etch chamber followed by recovering the rare gas from the pre-treated, rare-gas containing stream are disclosed. More particularly, the invention relates to the pretreatment and recovery of a rare gas, such as xenon or krypton, from a nitrogen-based exhaust stream with specific gaseous impurities generated during an etch process that is performed as part of a semiconductor fabrication process.

A catalyst for decomposing perfluorinated compounds includes an alumina carrier, at least one metal carried on the alumina carrier and selected from the group consisting of Zn, Ni, W, Zr, Ti, Ga, Nb, Co, Mo, V, Cr, Mn, Fe, and Cu, S carried on the alumina carrier, and rare-earth metals carried on the alumina carrier.

A method for preparing Cl—SO.sub.2NHSO.sub.2Cl including a step of chlorinating sulphamic acid with at least one chlorinating agent and at least one sulphur-containing agent, the method resulting in a flow F1, preferably liquid, including Cl—SO.sub.2NHSO.sub.2Cl and a gas stream F2 including HCl and SO.sub.2, the method including a step a) of treating the gas stream F2. Also, a method for preparing LiFSl including the abovementioned method for preparing Cl—SO.sub.2NHSO.sub.2Cl.

A system and a method for industrial plant or utility plant flue gas desulfurization, with zero waste water liquid discharge from a wet flue gas desulfurization system utilized therein, are disclosed herein. The wet flue gas desulfurization system is supplied an absorption liquid for contact with a flue gas to absorb flue gas acid gases. Waste water from the wet flue gas desulfurization system is heated under pressure in a heat exchanger to produce heated waste water, which is supplied to a flash vessel to produce steam. The produced steam is supplied to the flue gas upstream of a particulate collection system and the wet flue gas desulfurization system, supplied to the flue gas upstream of the wet flue gas desulfurization system, or supplied to absorption liquid circulated to the wet flue gas desulfurization system.

A system and a method for industrial plant or utility plant flue gas desulfurization, with zero waste water liquid discharge from a wet flue gas desulfurization system utilized therein, are disclosed herein. The wet flue gas desulfurization system is supplied an absorption liquid for contact with a flue gas to absorb flue gas acid gases. Waste water from the wet flue gas desulfurization system is heated under pressure in a heat exchanger to produce heated waste water, which is supplied to a flash vessel to produce steam. The produced steam is supplied to the flue gas upstream of a particulate collection system and the wet flue gas desulfurization system, supplied to the flue gas upstream of the wet flue gas desulfurization system, or supplied to absorption liquid circulated to the wet flue gas desulfurization system.

Dry processes, apparatus, compositions and systems are provided for reducing emissions of sulfur oxides, and sulfur dioxide in particular, and/or HCl and/or Hg in a process employing a combination of a lime-based sorbent, in particular hydrated lime and/or dolomitic hydrated lime, and a sorbent doping agent administered to achieve coverage of a three-dimensional cross section of a passage carrying SO.sub.x and/or HCl and/or Hg-containing gases with a short but effective residence time at a temperature effective to provide significant sulfur dioxide and/or HCl and/or Hg reductions with high rates of reaction and sorbent utilization. The once-through, dry process can advantageously introduce the sorbent and sorbent doping agent dry or preferably as a slurry to enable uniform treatment. Preferred sorbent doping agents include water-soluble or water-dispersible copper and/or iron compositions which can be heated to an active form in situ by the flue gases being treated.