Abstract: There is provided a process for preparing aluminium chloride comprising leaching aluminium dross residues with H2SO4 so as to obtain a leachate; and hydrochlorinating the leachate so as to obtain aluminium chloride. If desired, aluminium chloride can then be converted into alumina.

Abstract: There is provided a process for preparing aluminium chloride comprising: leaching aluminium dross residues with HCl so as to obtain a mixture comprising a solid and a liquid; and hydrochlorinating the liquid obtained from the mixture, so as to form a precipitate comprising aluminium chloride. Such a sequence can also be used for preparing alumina. In such a case, the process can further comprise the step of converting the so-obtained aluminium chloride into alumina. In the processes previously defined, the solid so-obtained can also be leached with H2SO4, thereby generating a leachate. The leachate can also eventually be hydrochlorinated so as to increase the yield of the desired product obtained i.e. alumina or aluminium chloride.

Abstract: There is provided a process for preparing aluminium chloride comprising leaching aluminium dross residues with H2SO4 so as to obtain a leachate; and hydrochlorinating the leachate so as to obtain aluminium chloride. If desired, aluminium chloride can then be converted into alumina.

Abstract: There is provided a process for preparing aluminium chloride comprising: leaching aluminium dross residues with HCl so as to obtain a mixture comprising a solid and a liquid; and hydrochlorinating the liquid obtained from the mixture, so as to form a precipitate comprising aluminium chloride. Such a sequence can also be used for preparing alumina. In such a case, the process can further comprise the step of converting the so-obtained aluminium chloride into alumina. In the processes previously defined, the solid so-obtained can also be leached with H2SO4, thereby generating a leachate. The leachate can also eventually be hydrochlorinated so as to increase the yield of the desired product obtained i.e. alumina or aluminium chloride.

Abstract: There is provided a process for reducing formaldehyde content of a gas comprising the step of contacting the gas with an aqueous oxidizing solution comprising at least one cation, a base, and H2O2 so as to oxidize at least a part of the formaldehyde contained in the gas into formic acid. Thus, a gas having a reduced content in formaldehyde as compared to the gas before the process and a solution comprising formic acid, are so-obtained. Such a process can be particularly useful for treating various types of gases containing formaldehyde.