Abstract: The present invention concerns a process for the hydroxyalkylation of a carbocyclic aromatic ether.The invention preferably relates to the preparation of 3-methoxy-4-hydroxybenzyl alcohol by the hydroxymethylation of guaiacol.It also concerns the oxidation of the hydroxyalkylated ethers obtained, in particular the oxidation of 3-methoxy-4-hydroxybenzyl alcohol to 3-methoxy-4-hydroxybenzaldehyde, commonly known as "vanillin".The process for the hydroxyalkylation of a carbocyclic aromatic ether of the invention consists of reacting the aromatic ether with a carbonyl compound in the presence of a catalyst and is characterized in that the hydroxyalkylation reaction is carried out in the presence of an effective quantity of a zeolite.

Abstract: The invention relates to the use of barium sulphide or strontium sulphide for the removal of heavy metals in industrial acidic solutions.The invention is applicable to the purification of contaminated acids, in particular of spent battery acid, or of industrial solutions of titanyl sulphate.

Abstract: The present invention concerns a process for the preparation of 3-carboxy-4-hydroxybenzaldehydes and derivatives thereof from phenolic compounds carrying formyl and/or hydroxymethyl groups in the 2 and 4 positions.The invention also concerns the preparation of 4-hydroxybenzaldehydes from 3-carboxy-4-hydroxybenzaldehydes.More particularly, the invention concerns the preparation of 3-methoxy-4-hydroxybenzaldehyde and 3-ethoxy-4-hydroxybenzaldehyde, respectively known as "vanillin" and "ethylvanillin".The process for the preparation of 3-carboxy-4-hydroxybenzaldehyde is characterized in that the group in the 2 position in a phenolic compound carrying formyl and/or hydroxymethyl groups in the 2 and 4 positions is selectively oxidized to a carboxy group, and optionally a hydroxymethyl group in the 4 position is selectively oxidized to a formyl group.A successive decarboxylation step for a 3-carboxy-4-hydroxybenzaldehyde produces a 4-hydroxybenzaldehyde.

Abstract: The invention relates to the production of solid, powdery carboxylates of Rare Earth elements, particularly Nd, La, Pr, and Ce, where the ligands coordinated to the metal are preferably long chain, branched carboxylic acids, most preferably 2-ethylhexanoic, neodecanoic (versatic) and naphthenic acids. The process involves batch precipitation of the product by utilizing Rare Earth water soluble salts, preferably Rare Earth nitrates, and salts of the carboxylic acid and washing the product with water, alcohol, water and alcohol mixtures or combinations thereof.

Abstract: The present invention relates to a method for reducing and removing inorganic impurities in sodium solutions by contact with activated carbon. Preferably, the activated carbon is saturated with organics. The process can provide for significant reduction of magnesium by as much as 50% and calcium by as much as 20%.

Abstract: The invention relates to a process of treatment for the recovery of the precious metals, such as platinum, rhodium and palladium, contained in various compositions including a layer of oxide(s) which is deposited on a metal support, in particular worn or spent motor vehicle postcombustion catalysts, in which the layer of oxide(s) containing the precious metals is separated from the metal support by an electrochemical route, the composition to be treated forming one of the electrodes employed or being in direct contact with one of the electrodes employed.

Abstract: The present invention relates to a novel presentation of a product exhibiting the phenomenon of supercooling. More precisely, the subject of the invention is cristallized pearls of a product exhibiting strong supercooling. The invention also relates to the preparation of the said pearls. The characteristic feature of the process of the invention is to melt, if necessary, the product to be shaped; to break up the molten mass into droplets; to cool the droplets to a temperature below the glass transition temperature of the product, so that these droplets harden by vitrification; to maintain the pearls thus vitrified at a temperature below the glass transition temperature and to place them in contact with crystallization seeds; to crystallize the pearls by raising the temperature above the glass transition temperature and then to recover the crystallized pearls.

Abstract: The subject of the present invention is a process for the preparation of a 4-hydroxybenzaldehyde carrying at least one substituent in the position ortho to the OH group.It more particularly relates to the preparation of 3-methoxy-4-hydroxybenzaldehyde and of 3-ethoxy-4-hydroxybenzaldehyde.The process for the preparation of a substituted 4-hydroxybenzaldlehyde, substituted at least in the 3 position by an alkoxy group, is characterized in that it comprises subjecting a substituted phenol compound, substituted at least in the 2 position by an alkoxy group and in which the 4 and 6 positions are free, to a first stage of carboxylation in the 6 position, then to a stage of hydroxymethylation in the 4 position, followed by a stage of oxidation of the hydroxymethyl group to a formyl group, and finally to a last decarboxylation stage.

Abstract: The present invention relates to a process for the preparation of carboxylic acids by controlled oxidation of the corresponding alkanes.The process according to the invention consists in reacting the alkane with a source of oxygen, the reaction being performed in the presence of a catalyst in which the active phase is based on vanadium, titanium, molybdenum, phosphorus and oxygen.

Abstract: The present invention concerns a process for the preparation of a rare-earth sulphide characterized in that a rare-earth halide is brought into the presence of an alkaline or aluminum halide and heated in the presence of hydrogen sulphide at a temperature which is sufficient to volatilize the halides.More particularly, the halide is a chloride, the rare-earth is cerium and the alkali is sodium.

Abstract: Mixed oxides of cerium and zirconium as well as solid solutions and cerium oxides are produced having improved thermal stability. The process involves the formation of cerium and zirconium oxides, mixed oxides and solid solutions by methods such as co-thermohydrolysis and co-precipitation, followed by washing or impregnating with an alkoxylated compound having greater than 2 carbon atoms. After the washing or impregnating step, the mixture is calcined to form oxides having very high surface area and oxygen storage capacity. The improved thermal stability of the oxides makes them advantageous for use in applications such as catalytic converters.

Abstract: The invention relates to the use as a luminophor in plasma systems of a compound based on an yttrium, lanthanum, gadolinium or lutecium phosphate doped with at least one rare earth chosen from the group comprising terbium, praseodymium, europium and cerium.

Abstract: Mixed oxides of cerium and zirconium as well as solid solutions and cerium oxides are produced having improved thermal stability. The process involves the formation of cerium and zirconium oxides, mixed oxides and solid solutions by methods such as co-thermohydrolysis and co-precipitation, followed by washing or impregnating with an alkoxylated compound having greater than 2 carbon atoms. After the washing or impregnating step, the mixture is calcined to form oxides having very high surface area and oxygen storage capacity. The improved thermal stability of the oxides makes them advantageous for use in applications such as catalytic converters.

Abstract: A process for the treatment of a glass to reduce or remove its wettability by gallium is provided, wherein the glass is treated with a silyling agent. Also is provided an apparatus comprising at least one hollow element containing a gallium or gallium based alloy or in which a gallium or gallium based alloy can circulate, wherein the glass forming the hollow element has been treated using the process. The apparatus may be thermometer, barometer or electric switch.