摘要:
A method for increasing the efficiency of xylene isomerization by using a two stage isomerization process. In the first stage of the process, a C.sub.9.sup.+ aromatics feedstock is subjected to ethylbenzene conversion and xylene isomerization. Non-C.sub.8 aromatics are removed from the effluent, which is then processed in a second stage of the process to remove para-xylene and isomerize the para-xylene depleted effluent. The effluent from the second stage isomerization unit is then recycled into the inlet of the second stage of the process and a slip stream from the para-xylene separator is recycled to the feedstock and to the effluent of the ethylbenzene conversion unit. In this way, the production of para-xylene is maximized. In a preferred embodiment, toluene is co-fed into the feedstock to minimize the loss of xylenes during the ethylbenzene conversion reaction.
摘要:
The space-time yield and/or the selectivity of the photochemical dimerization of alkanes, ethers, primary and secondary alcohols, phosphine oxides and primary, secondary and tertiary silanes with Hg and U.V. light is enhanced by refluxing the substrate in the irradiated reaction zone at a temperature at which the dimer product condenses and remains condensed promptly upon its formation. Cross-dimerization of the alkanes, ethers and silanes with primary alcohols is disclosed, as is the functionalization to aldehydes of the alkanes with carbon monoxide.
摘要:
The invention relates to a hydroprocessed product that can be produced by hydroprocessing tar, such as a tar obtained from hydrocarbon pyrolysis. The invention also relates to methods for producing such a hydroprocessed product, and the use of such a product, e.g., as a fuel oil blending component.
摘要:
The invention concerns integration of hydroprocessing and steam cracking. A feed comprising crude or resid-containing fraction thereof is treated by hydroprocessing and visbreaking and then passed to a steam cracker to obtain a product comprising olefins.
摘要:
The invention relates to upgraded pyrolysis products, processes for upgrading products obtained from hydrocarbon pyrolysis, equipment useful for such processes, and the use of upgraded pyrolysis products.
摘要:
The invention relates to regeneration of catalysts used in the purification of aromatics streams. It has been surprisingly found that retaining small amount of coke on the catalyst reduces regeneration costs and improves regeneration effectiveness.
摘要:
Catalysts for dewaxing of hydrocarbon feeds, particularly feeds with elevated sulfur and nitrogen levels, are provided. The dewaxing catalysts include a zeolite with a low silica to alumina ratio combined with a low surface binder, or alternatively the formulated catalyst has a high ratio of zeolite surface area to external surface area.
摘要:
The invention is a process for removing impurities from an aromatics stream and apparatus for the practice thereof, whereby trace olefins and dienes are removed from aromatic plant feedstocks using a reactor design that enables the product to be backmixed with the feedstock and that enables a feed/effluent heat exchanger.
摘要:
The invention concerns integration of hydroprocessing and steam cracking. A feed comprising crude or resid-containing fraction thereof is treated by hydroprocessing and visbreaking and then passed to a steam cracker to obtain a product comprising olefins.
摘要:
Water reacts on molecular sieve catalysts used in oligomerization reactions and forms oxygenated compounds, in particular organic acids that may cause corrosion problems downstream of the reactor, in particular in distillation tower overhead systems and downstream thereof. A lowering of the presence of water in the feed prior to contacting thereof with the molecular sieve brings a significant reduction in corrosion downstream. At the same time, it has a significant beneficial effect on catalyst activity and brings a significant extension of catalyst life. Lowering water in the feed is particularly effective when organic nitrogen-containing Lewis bases are present in the feed, even at low levels.