摘要:
The invention relates to a method for monitoring exothermic reactions in a reactor, in which one or more starting materials react exothermically to give at least one product, and at least one gas is present in the reactor during operation as intended or during a runaway, comprising the following process: A) measurement and storage of an initial temperature and an initial pressure in the reactor, B) calculation of the amount of products and starting materials present in the reactor from an energy balance, C) calculation of a maximum pressure raise that occurs on stepwise reaction of the amount of starting materials present, and D) calculation of a runaway pressure from the maximum pressure raise that occurs, calculated in step C), and the measured initial pressure stored in step A).
摘要:
The invention relates to a method for monitoring exothermic reactions in a reactor, in which one or more starting materials react exothermically to give at least one product, and at least one gas is present in the reactor during operation as intended or during a runaway, comprising the following process: A) measurement and storage of an initial temperature and an initial pressure in the reactor, B) calculation of the amount of products and starting materials present in the reactor from an energy balance, C) calculation of a maximum pressure raise that occurs on stepwise reaction of the amount of starting materials present, and D) calculation of a runaway pressure from the maximum pressure raise that occurs, calculated in step C), and the measured initial pressure stored in step A).
摘要:
Process for preparing polyolefins having high molecular weights in the presence of a catalyst comprising an organic transition metal compound in a gas-phase fluidized-bed reactor, where the polyolefins prepared have a melt flow rate at 2.16 kg and 190° C. in accordance with ISO 1133 of less than 4 g/10 min. According to the present invention, a start-up phase during which a polyolefin having an increased melt flow rate of above 4 g/10 min is produced for a transitional period is provided. In this way, trouble-free start-up of the reactor is ensured even in the case of polymer products having a high molecular weight and a melt flow rate below 4 g/10 min and even when using catalysts based on organic transition metal compounds, in particular metallocene catalysts.
摘要翻译:在气相流化床反应器中,在含有有机过渡金属化合物的催化剂存在下制备具有高分子量的聚烯烃的方法,其中制备的聚烯烃的熔体流动速率为2.16kg和190℃,根据 ISO 1133小于4 g / 10 min。 根据本发明,提供了一种启动阶段,其中在过渡时期内产生熔体流动速率增加至高于4g / 10min的聚烯烃。 这样即使在具有高分子量和低于4g / 10min的熔体流动速率的聚合物产物的情况下甚至在使用基于有机过渡金属化合物的催化剂时也能确保反应器的无故障启动, 特别是金属茂催化剂。
摘要:
An aqueous polymer dispersion is prepared by reacting at least one olefin in. the presence of at least one polymerization catalyst and one emulsifier in an aqueous medium by a process wherein the polymerization catalyst is prepared in an in situ reaction by reacting the ligand compound 2,6-dichloro-para-benzoquinone (Ia) and/or 2,3,6-trichloro-para-benzoquinone (Ib) with a phosphine compound or diphosphine compound and with a metal compound and the polymerization reaction is effected in an aqueous medium.
摘要:
An engine exhaust gas purification device comprising control unit having successively arranged switching device (1), counter-current heat exchanger (3) and at least one exhaust gas purification component (2). The switching device (1) has a first position where a flow path (6) of the exhaust gas to the exhaust gas purification component (2) is opened and a second position where a flow path (6) of the exhaust gas to the exhaust gas purification component (2) is blocked and the exhaust gas flows along a further flow path (7) where the exhaust gas is heated and conveyed, via a flow path (20) of the exhaust gas purification component (2), and exits the exhaust gas purification unit (5) through outlet channels (4) of the counter-current heat exchanger (3). The switching device, the exhaust gas purification component, the counter-current heat exchanger and the flow paths are integrated in a compact exhaust gas treatment unit.
摘要:
Process for the polymerization of ethylene or of ethylene with further 1-olefins, in which the ethylene is polymerized in the presence of a catalyst in a gas-phase reactor and reaction gas comprising propane and unpolymerized ethylene is circulated to remove the heat of polymerization, wherein the polymer particles are discharged continuously or discontinuously from the reactor, the polymer particles are separated from the major part of the concomitantly discharged gas and the polymer particles are degassed, the gas is freed of entrained fine particles and is separated from a low-boiling fraction comprising ethylene or from a high boiling fraction containing further 1-olefins or alkanes having from 4 to 12 carbon atoms in a first separation stage, a propane fraction is separated off in a second separation stage and this propane fraction is used for degassing the polymer particles discharged from the reactor, with the proportion of ethylene in the propane fraction being less than 1 mol % and the proportion of 1-olefins and alkanes having from 4 to 12 carbon atoms in the propane fraction being less than 4 mol %, in each case based on the total propane fraction. Furthermore, an apparatus for carrying out the process. In this way, a high heat discharge from the reactor, satisfactory degassing of the discharged polymer particles and recovery of the reaction gas discharged together with the polymer particles and also the gas used for degassing the polymer particles are made possible.
摘要:
An aqueous polymer dispersion is prepared by reacting at least one olefin in the presence of at least one polymerization catalyst and one emulsifier in an aqueous medium by a process wherein the polymerization catalyst is prepared in an in situ reaction by reacting the ligand compound 2,6-dichloro-para-benzoquinone (Ia) and/or 2,3,6-trichloro-para-benzoquinone (Ib) with a phosphine compound or diphosphine compound and with a metal compound and the polymerization reaction is effected in an aqueous medium.
摘要:
Process for the polymerization of ethylene or of ethylene with further 1-olefins, in which the ethylene is polymerized in the presence of a catalyst in a gas-phase reactor and reaction gas comprising propane and unpolymerized ethylene is circulated to remove the heat of polymerization, wherein the polymer particles are discharged continuously or discontinuously from the reactor, the polymer particles are separated from the major part of the concomitantly discharged gas and the polymer particles are degassed, the gas is freed of entrained fine particles and is separated from a low-boiling fraction comprising ethylene or from a high boiling fraction containing further 1-olefins or alkanes having from 4 to 12 carbon atoms in a first separation stage, a propane fraction is separated off in a second separation stage and this propane fraction is used for degassing the polymer particles discharged from the reactor, with the proportion of ethylene in the propane fraction being less than 1 mol % and the proportion of 1-olefins and alkanes having from 4 to 12 carbon atoms in the propane fraction being less than 4 mol %, in each case based on the total propane fraction. Furthermore, an apparatus for carrying out the process. In this way, a high heat discharge from the reactor, satisfactory degassing of the discharged polymer particles and recovery of the reaction gas discharged together with the polymer particles and also the gas used for degassing the polymer particles are made possible.
摘要:
In a method of removing volatile oxidizable compounds from particles present in a container, a gas stream is continuously introduced into the container, the gas stream takes up the oxidizable compound from the particles in the container and a gas stream laden with the oxidizable compound is discharged from the container. In the method of the present invention, oxygen is added to the gas stream which has been discharged and the oxidizable compound present in the discharged gas stream is subsequently at least partly catalytically oxidized by means of the oxygen and this oxidized gas stream forms at least part of the gas stream introduced, so that the gas stream is circulated. This makes safe and inexpensive removal of the oxidizable compounds from the particles possible.
摘要:
In EUV lithography apparatuses (10), it is proposed, in order to lengthen the lifetime of contamination-sensitive components, to arrange them in a protection module. The protection module comprises a housing (23-29) having at least one opening (37-47), in which at least one component (13a, 13b, 15, 16, 18, 19) is arranged and at which one or more gas feeds (30-36) are provided in order to introduce a gas flow into the housing (23-29), which emerges through the at least one opening (37-47). In order to effectively prevent contaminating substances from penetrating into the protection module, a light source (48-56) is arranged at the at least one opening (37-47), which light source illuminates the opening (37-47) with one or more wavelengths by which the contaminating substances can be dissociated before they penetrate through the opening (37-47).