摘要:
Catalyst comprising a nickel-based active phase and an alumina support, characterized in that: the nickel is distributed both on a crust at the periphery of the support, and in the core of the support, the thickness of said crust being between 2% and 15% of the diameter of the catalyst; the nickel density ratio between the crust and the core is strictly greater than 3; said crust comprises between 40% and 80% by weight of nickel element relative to the total weight of nickel contained in the catalyst.
摘要:
Catalyst comprising nickel and copper, in a proportion of 1% to 50% by weight of nickel element relative to the total weight of the catalyst, in a proportion of 0.5% to 15% by weight of copper element relative to the total weight of the catalyst, and an alumina support, said catalyst being characterized in that: the mole ratio between nickel and copper is between 0.5 and 5 mol/mol; at least one portion of the nickel and copper is in the form of a nickel-copper alloy; the nickel content in the nickel-copper alloy is between 0.5% and 15% by weight of nickel element relative to the total weight of the catalyst, the size of the nickel particles in the catalyst is less than 7 nm.
摘要:
Nickel and copper catalyst, and an alumina support: nickel distributed both in the core of and on a crust at the periphery of the support, crust thickness being 2% to 15% of catalyst diameter; nickel density ratio between the crust and the core greater than 3; crust contains more than 25% by weight of nickel element relative to total weight of nickel in the catalyst; mole ratio between nickel and copper is 0.5 to 5, at least one portion of nickel and copper is a nickel-copper alloy; nickel content in the nickel-copper alloy is 0.5% to 15% by weight of nickel element relative to total weight of the catalyst; size of the nickel particles in the catalyst is less than 7 nm.
摘要:
The present invention relates to the field of solid materials for the adsorption of lithium. In particular, the present invention relates to a novel process for preparing a solid crystalline material formed preferably in extrudate form, of formula (LiCl)x.2Al(OH)3,nH2O with n being between 0.01 and 10, x being between 0.4 and 1, comprising a step a) to precipitate boehmite under specific conditions of temperature and pH, a step to place the precipitate obtained in contact with a specific quantity of LiCl, at least one forming step preferably via extrusion, said process also comprising a final hydrothermal treatment step, all allowing an increase in lithium adsorption capacity and in the adsorption kinetics of the materials obtained compared to prior art materials, when used in a process to extract lithium from saline solutions.
摘要:
The present invention relates to the field of solid materials for the adsorption of lithium. In particular, the present invention relates to a new method for the preparation of a crystallized and shaped solid material, preferably in extruded form, of formula LiXx.2Al(OH)3,nH2O, wherein n is between 0.01 and 10, x is 1 when X is an anion selected from among chloride, hydroxide and nitrate anions, and x is 0.5 when X is an anion selected from among sulfate and carbonate anions, comprising a boehmite precipitation step a) under specific temperature and pH conditions, at least one basic mixing shaping step, wherein the method also comprises a final hydrothermal treatment step, all to increase the lithium adsorption capacity and the kinetics of adsorption of the materials obtained, compared with the materials of the prior art when it is used in a method for lithium extraction from saline solutions.
摘要:
A method for preparing a crystallized solid material of formula LiCl.2Al(OH)3,nH2O with n being comprised between 0.01 and 10, includes mixing in an aqueous medium, at least one source of alumina and at least one source of lithium in order to obtain a suspension, filtering the resulting suspension obtained for obtaining a slurry, followed by drying the obtained slurry at a temperature between 20 and 80° C. for a period between 1 h and 12 h, then shaping by extrusion the resulting dried slurry, directly after the drying to obtain extrudates, where the shaping was carried out without any binder, and then the drying of the obtained extrudates at a temperature comprised between 20 and 200° C. for a period between 1 hour and 20 hours, in order to obtain the crystallized solid material of formula LiCl.2Al(OH)3,nH2O as extrudates. A method for extracting lithium from saline solutions uses the thereby prepared material.
摘要:
Catalyst for the hydrogenation of aromatic compounds capable of being obtained by the process comprising at least the following stages: a) the alumina support is brought into contact with at least one organic additive; b) the alumina support is brought into contact with at least one nickel metal salt, the melting point of said metal salt of which is between 20° C. and 150° C.; c) the solid mixture obtained on conclusion of stages a) and b) is heated with stirring; d) the catalyst precursor obtained on conclusion of stage c) is dried; e) a stage of heat treatment of the dried catalyst precursor obtained on conclusion of stage d) is carried out.
摘要:
A process for preparing a catalyst for the hydrogenation of aromatic or polyaromatic compounds comprising nickel, copper and a support comprising at least one refractory oxide, comprising the following steps: bringing the support into contact with a solution containing at least one copper precursor and one nickel precursor; drying the catalyst precursor at a temperature of less than 250° C.; reducing the catalyst precursor by bringing said precursor into contact with a reducing gas at a temperature of between 150° C. and 250° C.; bringing the catalyst precursor into contact with a solution comprising a nickel precursor; a step of drying the catalyst precursor at a temperature of less than 250° C.; reducing the catalyst precursor by bringing said precursor into contact with a reducing gas at a temperature of between 150° C. and 250° C.
摘要:
A method for preparing a catalyst with a bimetallic active phase made of nickel and copper, and a support comprising a refractory oxide, wherein the method involves: a) placing the support in contact with at least one solution containing a nickel precursor; b) placing the support in contact with a solution containing a copper precursor; wherein a) and b) are carried out separately in any order; c) drying the catalyst precursor at the end of a) and b), or b) and a), at a temperature less than 250° C.; and d) supplying the catalyst precursor obtained at the end of c), into a hydrogenation reactor, and carrying out a reduction step by placing the precursor in contact with a reducing gas at a temperature of less than 200° C. and for a period greater than or equal to 5 minutes and less than 2 hours.
摘要:
A catalyst comprising palladium, a porous support comprising at least one refractory oxide selected from the group constituted by silica, alumina and silica-alumina, the palladium content in the catalyst being in the range 0.01% to 2% by weight with respect to the total catalyst weight, at least 80% by weight of the palladium being distributed in a crust at the periphery of said support, the thickness of said crust being in the range 20 to 100 μm, characterized in that said support is in the form of an extrudate and in that said support comprises a specific surface area in the range 165 to 250 m2/g.