Abstract: One aspect relates to a process for preparing a quartz glass body, including providing a silicon dioxide granulate, making a glass melt from the silicon dioxide granulate in a melting crucible, making a quartz glass body from at least a part of the glass melt, and treating the quartz glass body with at least one procedure selected from the group consisting of chemical, thermal or mechanical treatment to obtain a treated quartz glass body. One aspect also relates to a quartz glass body which is obtainable by this process. One aspect also concerns a light guide, an illuminant and a formed body each obtainable by processing the quartz glass body further.

Abstract: The invention relates to a process for the preparation of a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, wherein the silicon dioxide granulate was made from pyrogenic silicon dioxide powder and the silicon dioxide granulate has a BET surface area in a range from 20 to 40 m2/g, ii.) Making a glass melt out of silicon dioxide granulate in an oven and iii.) Making a quartz glass body out of at least part of the glass melt, wherein the oven has at least a first and a further chamber connected to one another via a passage, wherein the temperature in the first chamber is lower than the temperature in the further chambers. The invention further relates to a quartz glass body which is obtainable by this process. The invention further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

Abstract: The invention relates to a process for the preparation of a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate obtainable from a silicon dioxide powder, wherein the silicon dioxide granulate has a larger particle size than the silicon dioxide powder, ii.) Making a glass melt out of silicon dioxide granulate and iii.) Making a quartz glass body out of at least part of the glass melt, wherein the melting crucible has at least one inlet and at least one outlet, wherein at least part of the glass melt is removed via the melting crucible outlet. The invention further relates to a quartz glass body which is obtainable by this process. The invention further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

Abstract: One aspect relates to a light guide comprising a jacket and one or more cores, wherein the jacket surrounds the cores. Each core has a refractive index profile perpendicular to the maximum extension of the core, wherein at least one refractive index nK of each refractive index profile is greater than the refractive index nM1 of the jacket. The jacket is made of silicon dioxide and has an OH content of less than 10 ppm, a chlorine content of less than 60 ppm, and an aluminium content of less than 200 ppb. One aspect also relates to a silicon dioxide granulate I, characterized by a chlorine content of less than 200 ppm and an aluminium content of less than 200 ppb, in each case based on the total weight of the silicon dioxide granulate I.

Abstract: The invention relates to a process for the preparation of a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, ii.) Making a glass melt out of the silicon dioxide granulate and iii) Making a quartz glass body out of at least part of the glass melt, wherein the provision comprises the steps I. Providing a silicon dioxide powder with at least two particles made from a silicon-chlorine compound, II. Bringing the silicon dioxide powder into contact with steam to obtain a treated silicon dioxide powder and III. Granulating the treated silicon dioxide powder to obtain a silicon dioxide granulate, and wherein the chorine content of the silicon dioxide powder is greater than the chlorine content of the silicon dioxide granulate. The invention further relates to a quartz glass body which is obtainable by this process. The invention further relates to a process for providing a silicon dioxide granulate.

Abstract: One aspect relates to a process for the preparation of a quartz glass body, including providing a silicon dioxide granulate composed of a pyrogenic silicon dioxide powder, making a glass melt out of the silicon dioxide granulate and making a quartz glass body out of at least part of the glass melt. The quartz glass body has an OH content of less than 10 ppm, a chlorine content of less than 60 ppm and an aluminium content of less than 200 ppb. One aspect also relates to a quartz glass body which is obtainable by this process. Furthermore, one aspect relates to a formed body and a structure, each of which is obtainable by further processing of the quartz glass body.

Abstract: The invention relates to a process for the preparation of a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, ii.) Making a glass melt out of silicon dioxide granulate in an oven and iii.) Making a quartz glass body out of at least part of the glass melt, wherein the oven comprises a standing sinter crucible. The invention further relates to a quartz glass body which is obtainable by this process. The invention further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

Abstract: One aspect relates to a process for the preparation of a quartz glass body, including provision of a silicon dioxide granulate, making a glass melt from the silicon dioxide granulate and making a quartz glass body from at least part of the glass melt. The provision includes making a silicon dioxide powder with at least two particles prepared from a silicon-chlorine compound, bringing the silicon dioxide powder into contact with ammonia to obtain a treated silicon dioxide powder, and granulating the treated silicon dioxide powder to obtain a silicon dioxide granulate. The chlorine content of the silicon dioxide powder is greater than the chlorine content of the silicon dioxide granulate. One aspect relates further to a quartz glass body which is obtainable by this process. One aspect also relates to a process for the preparation of a silicon dioxide granulate.

Abstract: One aspect relates to a process for the preparation of a quartz glass body. The process includes providing a silicon dioxide granulate I prepared from a pyrogenically produced silicon dioxide powder, treating the silicon dioxide granulate I with a reactant at a temperature in a range from 1000 to 1300° C., and making a glass melt out of the silicon dioxide granulate. A quartz glass body is made out of at least a part of the glass melt. Furthermore, one aspect relates to a quartz glass body obtainable by this process. Furthermore, one aspect relates to a light guide, an illuminant, and a formed body, each of which is obtainable by further processing of the quartz glass body. One aspect additionally relates to a process for the preparation of a silicon dioxide granulate II.

Abstract: One aspect relates to a process for the preparation of a quartz glass grain, including providing a silicon dioxide granulate from a pyrogenically produced silicon dioxide powder, making a glass melt out of silicon dioxide granulate, making a quartz glass body out of at least part of the glass melt and reducing the size of the quartz glass body to obtain the quartz glass grain. One aspect further relates to a quartz glass grain which is obtainable by this process. One aspect further relates to opaque quartz glass bodies, which are obtainable by further processing of the quartz glass grain.

Abstract: A method for producing synthetic quartz glass by fusion of SiO2 granulate involves synthesizing amorphous SiO2 primary particles, granulating the amorphous SiO2 primary particles to form an open-pore SiO2 granulate, sintering the open-pore SiO2 granulate by heating in a sintering atmosphere at a sintering temperature and for a sintering period to form a densified SiO2 granulate, and melting the densified SiO2 granulate at a melting temperature to form the synthetic quartz glass. To provide an inexpensive production of low-bubble transparent components of quartz glass despite the use of still open-pore SiO2 granulate, the sintering atmosphere, sintering temperature and sintering duration are adjusted such that the densified SiO2 granulate still comprises open pores but manifests a material-specific infrared transmission T1700 at a wavelength of 1700 nm. This transmission is in the range of 50-95% of the infrared transmission T1700 of quartz glass granules of the same material.

Abstract: The invention relates to a method for economically producing a composite powder made of carbon and electrochemical active material. According to the invention, a melt made of a meltable carbon precursor substance having nanoparticles made of an active material distributed in the melt is provided, and said melt is divided into the composite powder, in which nanoparticles made of the active material are embedded in a matrix made of the carbon precursor substance. A porous composite material produced using the composite powder is used to produce an electrode for a secondary battery, in particular for use as an anode material.

Abstract: The invention relates to a composite made of a porous carbon and an active material containing sulphur and to method for producing same. A method for producing a composite made of a porous carbon structure and sulphur is disclosed, said composite being characterised by a high capacitance and a low capacitance loss, when used as an electrode material for a lithium-sulphur secondary battery. According to the invention, a dispersion of carbon powder, an active material containing sulphur and an aqueous medium are treated hydrothermally at a temperature sufficient for melting sulphur. The liquid phase which forms, which contains the melted sulphur and water, infiltrates the pores of the porous carbon.

Abstract: Methods for producing porous carbon product utilize template material in the form of template particles containing macropores and a polymerizable carbon precursor substance. The macropores of the template are infiltrated with the precursor substance in dissolved or melted form. After carbonization of the infiltrated precursor substance, the template is removed to form the porous carbon product. In order to obtain a carbon structure with hierarchical porosity having a high fraction of mesopores having pore sizes in the range of 2 to 50 nm, after the infiltration and before carbonization, the precursor substance within the macropores of the template is subjected to a treatment at a foaming temperature at which the precursor substance foams under polycondensation and fills the macropores as substantially mesoporous foam, in which at least 70% of the pores have pore sizes in the range of 10 to 150 nm.

Abstract: A method for producing carbon particles having a core/shell structure includes infiltrating a pore-containing template material with a first precursor for carbon of a first variety, carbonizing the first precursor to form a deposit of the carbon of the first variety, infiltrating the remaining pore space with a second precursor for carbon of a second variety to form a second deposit of the carbon of the second variety which has a second porosity lower than the first porosity, and removing the template material to form the carbon particles. The template material is provided as template particles and the first precursor is provided as precursor particles of meltable and polymerizable material. The infiltration occurs in the molten phase so that the first precursor is foamed before or during the carbonization to form a pore-containing carbon foam. In an intermediate product, pores of the template material are at least partially filled.

Abstract: Methods for producing porous carbon product utilize template material in the form of template particles containing macropores and a polymerizable carbon precursor substance. The macropores of the template are infiltrated with the precursor substance in dissolved or melted form. After carbonization of the infiltrated precursor substance, the template is removed to form the porous carbon product. In order to obtain a carbon structure with hierarchical porosity having a high fraction of mesopores having pore sizes in the range of 2 to 50 nm, after the infiltration and before carbonization, the precursor substance within the macropores of the template is subjected to a treatment at a foaming temperature at which the precursor substance foams under polycondensation and fills the macropores as substantially mesoporous foam, in which at least 70% of the pores have pore sizes in the range of 10 to 150 nm.

Abstract: Known lithium-ion cells for a secondary battery including an electrode have an active material layer containing active material particles in contact with a non-aqueous electrolyte and a particulate, porous additive. Using this as a basis, it is desired to achieve an improvement in the lithium-ion cells in respect of their gravimetric and volumetric energy density and in respect of inexpensive and reproducible production, and in particular to ensure that the desired properties of the active material layer are not changed, or are not changed to an unacceptable degree, by compression during calendering. Accordingly, it is proposed to use, as an additive, porous carbon particles having a porosity in the range between 50% and 95% and having macropores which are fluidically connected to one another and which are delimited by carbon walls having an average wall thickness in the range of 5 to 500 nm.

Abstract: A method for producing synthetic quartz glass by fusion of SiO2 granulate involves synthesizing amorphous SiO2 primary particles, granulating the amorphous SiO2 primary particles to form an open-pore SiO2 granulate, sintering the open-pore SiO2 granulate by heating in a sintering atmosphere at a sintering temperature and for a sintering period to form a densified SiO2 granulate, and melting the densified SiO2 granulate at a melting temperature to form the synthetic quartz glass. To provide an inexpensive production of low-bubble transparent components of quartz glass despite the use of still open-pore SiO2 granulate, the sintering atmosphere, sintering temperature and sintering duration are adjusted such that the densified SiO2 granulate still comprises open pores but manifests a material-specific infrared transmission T1700 at a wavelength of 1700 nm. This transmission is in the range of 50-95% of the infrared transmission T1700 of quartz glass granules of the same material.

Abstract: The invention relates to a method for economically producing a composite powder made of carbon and electrochemical active material. According to the invention, a melt made of a meltable carbon precursor substance having nanoparticles made of an active material distributed in the melt is provided, and said melt is divided into the composite powder, in which nanoparticles made of the active material are embedded in a matrix made of the carbon precursor substance. A porous composite material produced using the composite powder is used to produce an electrode for a secondary battery, in particular for use as an anode material.

Abstract: The invention relates to a composite made of a porous carbon and an active material containing sulphur and to method for producing same. A method for producing a composite made of a porous carbon structure and sulphur is disclosed, said composite being characterised by a high capacitance and a low capacitance loss, when used as an electrode material for a lithium-sulphur secondary battery. According to the invention, a dispersion of carbon powder, an active material containing sulphur and an aqueous medium are treated hydrothermally at a temperature sufficient for melting sulphur. The liquid phase which forms, which contains the melted sulphur and water, infiltrates the pores of the porous carbon.