Abstract: Monomethyl branched C10-C15 paraffins or olefins are recovered from a mixture comprising other nonnormal hydrocarbons such as di-isoparaffins, di-isoolefins, naphthenes and aromatics by adsorptive separation in a process which includes a prepulse step. In the prepulse step nonnormal hydrocarbons which are readily separated from the product is passed into the adsorbent bed immediately before or with the feed stream. This increases the selectivity of the system and allows for easier separation of the desired hydrocarbons. The recovered monomethyl hydrocarbons may then be used to form a monomethyl branched alkylaromatic hydrocarbon useful as a detergent precursor.

Abstract: For the removal of trace quantities of iodine-containing contaminants from corrosive liquid feed streams, an alternative with distinct advantages over the prior art is provided. The treatment method involves the use of a crystalline manganese phosphate which has been cation-exchanged with an iodine-reactive metal. This inorganic adsorbent may be used in unbound form, or it can bound with a substantially insoluble porous inorganic refractory metal oxide binder. A reactivation technique for this material is also presented.

Abstract: A process for the production of a carboxylic acid in the presence of solid catalyst particles that employs a flash step with a liquid wash is disclosed. This process helps prevent the buildup of deposits of solid catalyst particles, attrited solid catalyst particles, and heavy by-products in the flash zone. This invention is useful for the production of carboxylic acids, especially acetic acid.

Abstract: A process for the production of a carboxylic acid in the presence of solid catalyst particles that uses the exothermic heat of reaction with high efficiency in recovering the carboxylic acid product is disclosed. This process uses indirect heat exchange to transfer the heat of reaction to another stream, without the need for an additional heat transfer fluid such as steam. This invention is especially applicable to the production of acetic acid.

Abstract: A molecular sieve guard bed used in an adsorptive process for separating olefinic hydrocarbons from paraffinic hydrocarbons is regenerated in a method which recovers valuable hydrocarbons from the guard bed void volumes. The method comprises first contacting the sieve with a purge stream, with the initial effluent of the guard bed passed into a raffinate column to recover the olefinic hydrocarbons in the void volume of the bed. The flow of the effluent of the guard bed is then switched to a different fractionation column.

Abstract: For the removal of trace quantities of iodine-containing contaminants from corrosive liquid feed streams, an adsorbent with distinct advantages over prior-art materials is provided. The treatment method involves the use of a metal phthalocyanine compound where the metal selected from the group consisting of silver, mercury, copper, lead, thallium, palladium, or mixtures thereof. Such metals are known to be reactive with the iodine-containing contaminants in the feed stream. Furthermore, the metal phthalocyanine is deposited on a carrier material selected from the group consisting of an activated carbon, a phenolic polymer, and an inorganic refractory metal oxide. Such adsorbent materials have proven substantially insoluble even in corrosive liquid feed streams associated with the invention. Reactivation and regeneration techniques, which are generally incompatible with prior-art adsorbent materials, are also disclosed.

Abstract: A solution is provided to the long sought inorganic alternative to resin based adsorbents for iodide clean-up service for corrosive organic liquid. The solution involves the use of a solid inorganic adsorbent comprising a combination of a silica-rich zeolite molecular sieve, which has been cation-exchanged with an iodide-reactive metal selected from silver, mercury, copper, lead, thallium, palladium or mixtures thereof, with a substantially insoluble, porous refractory inorganic oxide binder. Reactivation and regeneration technique for the spent inorganic adsorbent are also covered.

Abstract: The feedstock to an aromatization process is processed by a selective adsorption step to remove hydrocarbon species, particularly indan, which have a severe adverse effect on aromatization catalyst stability. The feedstock preferably is a paraffinic raffinate from aromatics extraction. The intermediate from the adsorption step is particularly suitable for the selective conversion of paraffins to aromatics using a high-activity dehydrocyclization catalyst with high aromatics yields and long catalyst life.

Abstract: Metaxylene is recovered from admixture with other C.sub.8 aromatic hydrocarbons including orthoxylene by liquid phase adsorptive separation using a sodium exchanged Y zeolite as the adsorbent. Performance is improved by maintaining the adsorbent in a narrow range of temperature and hydration. These conditions allow the metaxylene to be recovered in a single raffinate process without costly prefractionation for orthoxylene removal. A novel desorbent, indane, is also disclosed.

Abstract: The cost of separating para-xylene from other xylene isomers and C.sub.9 aromatics by adsorption on zeolitic molecular sieves is reduced by the use of 1,4 diisopropylbenzene as a relatively high boiling desorbent. The desorbent has surprisingly high strength and selectivity characteristics with the preferred desorbent. The preferred adsorbent is an X zeolite containing barium or both barium and potassium ions at exchangeable cationic sites. The para-xylene components are selectively adsorbed onto the adsorbent. The non-adsorbed feed is then removed from the adsorbent and the para-xylene recovered by desorption.

Abstract: A process for removing sulfur containing compounds from various hydrocarbon streams is disclosed and claimed. The process involves contacting the feedstream with an adsorbent such as nickel exchanged zeolite X or Y, or a smectite layered clay having a surface area of at least 150 m.sup.2 /g, thereby adsorbing the sulfur compounds onto the adsorbent.

Abstract: A novel continuous process for the preparation of alkylated benzenes effected by solid catalysts which become deactivated under alkylation conditions uses a single catalyst zone for both reaction and catalyst flushing to prevent deactivation. The process utilizes a pulsed flow of the linear monoolefins into the catalyst zone during a reaction cycle with benzene acting as a desorbent for catalyst deactivating agents to prevent significant catalyst deactivation. The process can be generalized to encompass many types of reactions.

Abstract: The present invention is a process for separating at least a first component from a second component of at least a first stream within a single vessel having at least one distillation zone and an adsorption zone. The invention may be applied to separates an alcohol from a mixture of the alcohol and water, such as separating isopropyl alcohol from a mixture of isopropyl alcohol and water. The invention may be applied to more complex systems such as separating isopropyl alcohol and separating diisopropyl ether from the effluents of each reactor of a two-stage diisopropyl ether production process. The benefit of the invention is a high purity separation process at reduced capital equipment costs.

Abstract: The present invention is a single vessel apparatus for separating at least a first component from a second component of a process stream. The apparatus has a vertically-elongated vessel which contains a plurality of vertically spaced apart distillation contactors for vapor and liquid distillation and an adsorbent-retaining volume defined at least in part by a solids-impermeable member located above the contactors for passing a fluid into the retaining volume. The apparatus also contains a mechanism for adding adsorbent above the solids-impermeable member and a mechanism for withdrawing adsorbent particles from the retaining volume to contact the fluid with adsorbent particles and to provide at least intermittent downward gravity flow of adsorbent particles through the retaining volume and to selectively adsorb a portion of the fluid.

Abstract: The cost of separating para-xylene from other xylene isomers and C.sub.9 aromatics by adsorption on zeolitic molecular sieves is reduced by the use of certain relatively high boiling desorbents including 1,4 diisopropylbenzene. Preferably the adsorbent is an X zeolite adsorbent containing barium or both barium and potassium ions at exchangeable cationic sites. The para-xylene components are selectively adsorbed onto the adsorbent. The non-adsorbed feed is then removed from the adsorbent and the para-xylene recovered by desorption. Any C.sub.9 aromatic hydrocarbons and the other xylene isomers in the raffinate can be separated from these heavy desorbents by fractionation of the raffinate and the desorbent can be recycled to the process.

Abstract: Lactic acid formed via fermentation generally is susceptible to the development of color bodies when heated to temperatures of approximately 180.degree. C. and above. Color development appears to result from carbonization of small amounts of carbohydrates. Consequently a heat-stable lactic acid may be produced by subjecting an aqueous solution of lactic acid to temperatures between about 180 and 230.degree. C. for a time sufficient to carbonize the carbohydrates, with subsequent removal of the color bodies using standard decolorants such as activated charcoal. Heat treatment may be applied either directly to the broth or to an aqueous solution resulting from one or more processing steps applied to the fermentation broth.

Abstract: Ethylbenzene is recovered from a mixture of C.sub.8 aromatic hydrocarbons including xylenes by adsorptive separation in a narrow temperature range using a cesium exchanged X zeolite as the adsorbent. A mixture of diethylbenzene and toluene is the preferred desorbent.

Abstract: Metaxylene is recovered from a mixture of C.sub.8 aromatic hydrocarbons including other xylenes by liquid phase adsorptive separation using a sodium or sodium and lithium exchanged Y zeolite as the adsorbent. Performance is improved by maintaining the adsorbent in a narrow range of temperature and hydration. Toluene is the preferred desorbent.

Abstract: A process for removing sulfur containing compounds from various liquid organic feedstreams has been developed. The process involves contacting the feed stream with a metal oxide solid solution which adsorbs the sulfur containing compounds. Examples of these solid solutions are Mg/Al and Ni/Mg/Al oxide solid solutions.

Abstract: The separation of durene in high purity from coal tar or petroleum fractions by an adsorptive chromatographic process and liquid phase with lithium-exchanged X zeolite as the adsorbent and liquid aromatic desorbents.