Abstract:
PROBLEM TO BE SOLVED: To provide a fuel cell operable at 950 deg.C or less. SOLUTION: This fuel cell contains a cathode, an anode, and an electrolyte, and the cathode contains a material represented by the composition formula (Sr1-x Cax )1-y Ay Mn1-z Bz O3-δ . (In the formula, A represents at least one element selected from a group comprising Ba, Pb, Na, K, Y, and La; B represents at least one element selected from a group comprising Mg, Al, Ga, In, Sn, and elements of the subgroup 4, the subgroup 5, and the subgroup 6 in the periodic table of the elements; x is represents a value of 0.2-0.8; y represents a value of 0-0.4; z represents a value of 0 to less than 1, and δ represents a value necessary for satisfying the principle of electrical neutrality.) The fuel cell operating at moderate temperature is provided.
Abstract:
The invention relates to reaction membranes that contain a selective oxidation catalyst disposed on a ceramic membrane that selectively conducts oxide ions and that is composed of (Sr1-xCax)1-yAyMn1-zBzO3- delta , wherein A represents Ba, Pb, Na, K, Y, an element of the lanthanide group or a combination of these elements, B represents Mg, Al, Ga, In, Sn, an element of the 3d or 4d period or a combination of these elements, x is a number of from 0.2 to 0.8, y is a number of from 0 to 0.4, z is a number of from 0 to 0.6 and delta is a number that results from the principle of electroneutrality on the basis of x, y and z. The inventive reaction membranes are suitable for use in oxidative reactions of hydrocarbons in which oxygen is used.
Abstract:
The invention relates to a method for producing N-phosphonomethylglycine from an aqueous mixture containing N-phosphonomethylglycine, ammonium halogenides and alkali halides or earth alkali halides and optionally, organic impurities in a dissolved form. According to the invention, (a) the pH-value of the mixture is regulated to a value of 2 - 8, (b) the mixture is separated by means of a selective nano-filtration membrane, to obtain a retentate rich in N-phosphonomethylglycine and poor in halogenides and a permeate rich in halogenides and poor in N-phosphonomethylglycine and (c) the N-phosphonmethylglycine is prepared from the retentate. The inventive method enables the production of N-phosphonomethylglycine by simultaneously separating the halogenide salts thereof.
Abstract:
The invention relates to phosphacyclohexanes of general formulae I and II, wherein the following designations, among others, apply: R can represent hydrogen, C1-100-alkyl, C7-20-aralkyl, C7-20-alkaryl, and C6-12-aryl; R to R can independently represent hydrogen, C1-20-alkyl, C7-20-aralkyl, C7-20-alkaryl, and C6-12-aryl; W, W' can independently represent single bonds or bridges comprising 1 to 20 carbon atoms, which can form part of a cyclic or aromatic group and can be interrupted by heteroatoms. Said phosphacyclohexanes are used as ligands in transition metal complexes of transition metals belonging to groups VIII to X of the periodic table.
Abstract:
The invention relates to a method for producing oligomers, primarily consisting of repeating units, derived from 1 or 2-butene, from a hydrocarbon stream that essentially consists of branched and linear hydrocarbon compounds with 4 carbon atoms and contains olefinically branched and linear hydrocarbon compounds with 4 carbon atoms (parent stream C4). According to said method, the parent stream C4 is brought into contact with a membrane.
Abstract:
The invention relates to a method for producing sodium dithionite comprising the steps (a) production of a synthesis batch consisting of sodium formate, sulphur dioxide and an alkaline sodium compound in an aqueous methanol solvent, which forms a sodium dithionite mother liquor, (b) separation of the sodium dithionite from the sodium dithionite mother liquor, leaving a residual mother liquor, (c) separation of methanol from the residual mother liquor, (d) separation of the residual mother liquor into a first sub-stream that is rich in thiosulphate and a second sub-stream that is devoid of thiosulphate, but contains formate by means of a nanofiltration, (e) concentration of sodium formate in the second sub-stream and (f) return of the concentrated second sub-stream to step (a).
Abstract:
Disclosed is a method for processing naphtha, according to which a) naphtha or a stream generated from naphtha in a preprocessing step is divided into a stream A that is stripped of aromatics and a stream B which is enriched with aromatics in a membrane unit, the aromatics concentration in stream A ranging from 2 to 12 percent by weight (step a); b) partial stream A is directed at least in part into a steam cracker (step b); c) partial stream B is directed at least in part into a unit in which said stream B is divided into a stream C or several streams C' C'', C''',..., which has/have a lower aromatics content than stream B, and a stream D or several streams D', D'', D''',..., which has/have a higher aromatics content than stream B, by means of a thermal process (step c); d) stream C or at least one of the streams C', C'', C''' is delivered as a whole or in part to the feed for the steam cracker or directly to the steam cracker (step d).
Abstract:
Composite membranes comprising at least one porous substrate layer and at least one microporous separation layer, comprising at least one zeolite of the MFI type, are described, the separation layer being produced by a hydrothermal synthesis in which the molar ratio of silicon to aluminum is greater than 120 and the separation layer contains less than 10% by weight of aluminum in elemental or chemically bound form in a zone of at least 100 nm adjacent to the separation layer.
Abstract:
Procedimiento para la separación de nafta, en el que a) se separa nafta o una corriente de nafta, generada en una etapa de tratamiento previo, en una unidad de membrana, en una corriente A, empobrecida en hidrocarburos aromáticos y en una corriente B, enriquecida en hidrocarburos aromáticos, siendo la concentración de los hidrocarburos aromáticos en la corriente A desde un 2 hasta un 12 % en peso, b) la corriente parcial A se envía, al menos en parte, hasta una unidad de craqueo con vapor, c) la corriente parcial B se envía, al menos en parte, hasta una unidad, en la que se separa, por medio de un procedimiento térmico, en una corriente C empobrecida en hidrocarburos aromáticos, frente a la corriente B o en varias corrientes C'', C", C"'', ... que presentan, respectivamente, contenidos en hidrocarburos aromáticos menores que la corriente B, y en una corriente D enriquecida en hidrocarburos aromáticos, frente a la corriente B o en varias corrientes D'', D", D''", ... que presentan, respectivamente, contenidos en hidrocarburos aromáticos mayores que la corriente B, d) la corriente C o bien al menos una de las corrientes C'', C", C"'' se alimenta, respectivamente, en su totalidad o en parte, a la alimentación de la unidad de craqueo con vapor o a la propia unidad de craqueo con vapor.