Abstract:
The present invention relates to a process for improving the overall selectivity of an EO process for converting ethylene to ethylene oxide utilizing a highly selective EO silver catalyst containing a rhenium promoter wherein following normal operation a hard strip of the chloride on the surface of the catalyst is conducted in order to remove a portion of the chlorides on the surface of the catalyst. Following the hard strip, the catalyst is optionally re-optimized. Surprisingly, it has been found that the selectivity of the catalyst following the hard strip may be substantially higher than the selectivity prior to the hard strip.
Abstract:
A process for the epoxidation of an olefin, which process comprises reacting a feed comprising the olefin, oxygen and a reaction modifier in the presence of a highly selective silver-based catalyst at a reaction temperature T, and with the reaction modifier being present in a relative quantity Q which is the ratio of an effective molar quantity of active species of the reaction modifier present in the feed to an effective molar quantity of hydrocarbons present in the feed, and which process comprises the steps of: operating at a first operating phase wherein the value of T is T1 and the value of Q is Q1, and subsequently operating at a second operating phase at a reaction temperature which is different from the reaction temperature employed in the first operating phase, such that the value of T is T2 and the value of Q is substantially Q2, whereby Q2 is determined by calculation and Q2 is defined by the formula Q2=Q1+B(T2−T1), wherein B denotes a constant factor which is greater than 0; a reaction system suitable for performing the process for the epoxidation of an olefin; a computer program product which comprises a computer readable program recorded on a computer readable medium, suitable for instructing a data processing system of a computer system to execute calculations for the process for the epoxidation of an olefin; and a computer system which comprises the computer program product and a data processing system.
Abstract:
A process for the epoxidation of an olefin, which process comprises reacting a feed comprising the olefin, oxygen and a reaction modifier in the presence of a highly selective silver-based catalyst at a reaction temperature T, and with the reaction modifier being present in a relative quantity Q which is the ratio of an effective molar quantity of active species of the reaction modifier present in the feed to an effective molar quantity of hydrocarbons present in the feed, and which process comprises the steps of: operating at a first operating phase wherein the value of T is T1 and the value of Q is Q1, and subsequently operating at a second operating phase at a reaction temperature which is different from the reaction temperature employed in the first operating phase, such that the value of T is T2 and the value of Q is substantially Q2, whereby Q2 is determined by calculation and Q2 is defined by the formula Q2=Q1+B(T2−T1), wherein B denotes a constant factor which is greater than 0; a reaction system suitable for performing the process for the epoxidation of an olefin; a computer program product which comprises a computer readable program recorded on a computer readable medium, suitable for instructing a data processing system of a computer system to execute calculations for the process for the epoxidation of an olefin; and a computer system which comprises the computer program product and a data processing system.
Abstract:
Processes for the epoxidation of ethylene are provided in which, following start-up, an epoxidation catalyst is contacted with a feed comprising ethylene, oxygen, carbon dioxide in an amount below 2.0 vol. %, and a chloride moderator to achieve a desired work rate at a first operating temperature T1. The composition of the feed is subsequently adjusted (e.g., by decreasing the ethylene concentration, decreasing the oxygen concentration, increasing the carbon dioxide concentration and/or adjusting the concentration of the chloride moderator) so as to increase the first operating temperature T1 to a second operating temperature T2 while maintaining the desired work rate. As the catalyst activity declines, the composition of the feed is further adjusted so as to maintain the desired work rate at the second operating temperature T2.
Abstract:
A process for the production of an olefin oxide, which process comprises reacting a feed comprising an olefin and oxygen in a reactor tube in the presence of a silver-containing catalyst, wherein the presence of water in the catalyst bed is controlled such that the ratio of the partial pressure of water (PPH2O) divided by the vapor pressure of water (VPH2O) is less than 0.006, preferably less than 0.004.
Abstract:
A process for the production of an olefin oxide, which process comprises reacting a feed comprising an olefin and oxygen in a reactor tube in the presence of a silver-containing catalyst, wherein the presence of water in the catalyst bed is controlled such that the ratio of the partial pressure of water (PPH2O) divided by the vapor pressure of water (VPH2O) is less than 0.006, preferably less than 0.004.
Abstract:
The present invention relates to a process for improving the selectivity of an EO process utilizing a highly selective EO catalyst. In particular, the present invention is an improvement in the initial operation of a process for manufacturing ethylene oxide by contacting ethylene, oxygen, a chloride moderator and a hydrocarbon co-moderator with a high selectivity silver-containing catalyst at a concentration of carbon dioxide of less than about 2 mole percent, wherein the initial operating temperature is determined by optimization of such initial operating temperature at a level higher than the normal low initial operating temperature that is typically selected to obtain a longer operating cycle.
Abstract:
A reaction system for epoxidation of olefins, with a feed control system configured to control the relative quantity of reaction modifier present in the feed, where the relative quantity of said reaction modifier is changed in response to changes in the reaction temperature.
Abstract:
A reactor system for the epoxidation of ethylene, which reactor system comprises an elongated tube having an internal tube diameter of more than 40 mm, wherein contained is a catalyst bed of catalyst particles comprising silver and a promoter component deposited on a carrier, which promoter component comprises an element selected from rhenium, tungsten, molybdenum and chromium; a process for the epoxidation of ethylene comprising reacting ethylene with oxygen in the presence of the catalyst bed contained in the reactor system; and a method of preparing ethylene glycol, an ethylene glycol ether or an ethanol amine comprising obtaining ethylene oxide by the process for the epoxidation of ethylene, and converting the ethylene oxide into ethylene glycol, the ethylene glycol ether, or the ethanol amine. Preferably, the internal tube diameter is at least 45 mm.