Abstract: A complex alcohol ester which comprises the reaction product of an add mixture of the following: a polyhydroxyl compound represented by the general formula:R(OH).sub.nwherein R is any aliphatic or cyclo-aliphatic hydrocarbyl group and n is at least 2, provided that the hydrocarbyl group contains from about 2 to 20 carbon atoms; a polybasic acid or an anhydride of a polybasic acid, provided that the ratio of equivalents of the polybasic acid to equivalents of alcohol from the polyhydroxyl compound is in the range between about 1.6:1 to 2:1; and a monohydric alcohol, provided that the ratio of equivalents of the monohydric alcohol to equivalents of the polybasic acid is in the range between about 0.84:1 to 1.2:1; wherein the complex alcohol ester exhibits a pour point of less than or equal to -20.degree. C., a viscosity in the range between about 100-700 cSt at 40.degree. C. and having a polybasic acid ester concentration of less than or equal to 70 wt. %, based on the complex alcohol ester.

Abstract: A new composition of matter, a method for the preparation of a rubidium exchanged Type X structured zeolite and a separation process employing the same. The zeolite adsorbent is prepared by a procedure employing the aqueous ion exchange step and a final activation step including contacting a sodium-X zeolite with a rubidium salt in aqueous solution. The process involves the selective separation of ethylbenzene from a C.sub.8 aromatic isomer mixture containing ethylbenzene and employs the use of the rubidium exchanged type X structured zeolite in an adsorption separation process.

Abstract: Dual desorbent composition and/or dual temperature technique, when employed in a simulated moving-bed adsorption-desorption separation system embedded with a solid sorbent comprising certain sieves, e.g., Rb-exchanged Type X crystalline aluminosilicate sieve, which preferentially adsorb ethylbenzene, entails an improved separation and recovery of ethylbenzene from C.sub.8 aromatic feedstreams as sorbate product. Further, certain specific sieves, which preferentially adsorb xylene isomers, i.e., orthoxylene, metaxylene and paraxylene, may also be employed, in said simulated process utilizing the dual desorbent composition and/or the dual temperature concept, in order to effect the improved separation and recovery of ethylbenzene from its C.sub.8 aromatic isomers as raffinate product.

Abstract: Dual desorbent composition and dual temperature techniques as improvements for simulated moving-bed adsorption-desorption separation processes whereby certain hydrocarbons can be separated from mixtures containing various unsaturated and/or saturated aliphatic and/or aromatic hydrocarbons. The dual desorbent composition technique is implemented by employing a strong desorbent stream in the desorption zone and a weaker desorbent stream in the rectification zone of a simulated moving-bed countercurrent adsorption-separation system; while the dual temperature concept envisions the temperature differentiation between the desorption zone and the remaining zones of said separation system in order to both minimize the desorbent requirement and enhance the purity of the separation products. A combined use of both the dual desorbent composition and the dual temperature techniques can further improve the performance of said simulated moving-bed system.

Abstract: Dual desorbent composition and dual temperature techniques are provided as improvements for a simulated moving bed adsorption-desorption separation process which help reduce total desorbent requirements. The invention describes a process for continuously separating, in a liquid phase, components of a C.sub.8 aromatic feed mixture by contacting said feed mixture with a solid sorbent and utilizing a simulated countercurrent flow system wherein a liquid stream flows through serially and circularly interconnected desorption, rectification and sorption zones. One of the embodiments envisioned in the present improved process is directed to the employment of two desorbent streams of different strengths. This embodiment minimizes total amount of desorbent requirements by using a strong desorbent stream in the desorption zone and a suitable weaker desorbent stream in the rectification zone to achieve the desired separation.

Abstract: Simulated moving bed processes for the separation of C.sub.8 aromatic isomers using molecular sieve adsorbents are improved by the use of meta-diisopropylbenzene as the eluting agent. The invention describes a process for continuously separating, in a liquid phase, components of the feed mixture by contacting said feed mixture with a solid sorbent and utilizing a simulated countercurrent flow system wherein a liquid stream flows through serially and circularly interconnected desorption, rectification and sorption zones.

Abstract: In a liquid chromatography commercial process for the separation of two or more components contained in admixture in a feedstream including the steps of (a) contacting the feedstream mixture containing the components to be separated with a bed of crystalline aluminosilicate adsorbent at conditions to effect the selective retention of two or more of the components by said adsorbent, (b) passing through said bed an eluent selected from the group consisting of aromatics and substituted aromatics, (c) increasing the strength of the eluting agent in the liquid carrier during the operation of the steps (a) and (b) above, (d) recovering from said bed a stream or streams containing at least a portion of the less selectively adsorbed components, and (e) recovering a stream substantially enhanced in concentration of said selectively adsorbed components relative to other components of feedstream wherein the improvement comprises preheating the eluting agent of step (c) above prior to passing it through said bed at tempe