Abstract: The process for the separation of isomeric dichlorotoluenes, comprising the steps of:(a) passing a mixture containing isomeric dichlorotoluenes over a zeolite of the ZSM5 type having the composition (expressed in molar ratios) of (0.9+0.2) M.sub.2/n O:Al.sub.2 O.sub.3 : (10-100) SiO.sub.2 : z H.sub.2 O in which M is at least one cation selected from H, an alkali metal, an alkaline earth metal or a tetraalkylammonium cation; n is the valency of M; and z is between 0 and 40:(b) separating the non-adsorbed dichlorotoluenes;(c) contacting the zeolite containing the adsorbed isomers with an eluent; and(d) separating the isomers from the eluent.

Abstract: The invention relates to a process for separating mixed monochlorotoluene isomers, which comprises a first stage of adsorption carried out by passing said mixture through at least one column filled with a zeolite, and a second stage of deadsorption from said zeolite carried out by passing two deadsorbents in succession in the vapor phase through the column.

Abstract: A process for separating dichlorotoluene isomers from a mixture containing at least two dichlorotoluene isomers comprising(a) passing said mixture containing dichlorotoluene isomers through a mordenite having the following composition; in molar ratios:a H.sub.2 O: b M.sub.2/n O: Al.sub.2 O.sub.3 : (10-400 SiO.sub.2)in which M is hydrogen or at least one cation selected from an alkali metal or an alkaline-earth metal with the exception of cesium and rubidium, n is the valence of M, 0.7.ltoreq.a+b.ltoreq.1.1, and 0.ltoreq.b.ltoreq.0.2,(b) separating the non-adsorbed dichlorotoluenes from said mordenite,(c) contacting said mordenite containing the adsorbed isomers with a desorbent capable of separating said isomers from said mordenite, and(d) separating the desorbed isomers from the desorbent.

Abstract: There is provided a process for the separation of aromatic hydrocarbons mixtures into single components, in which the mixtures in vapor phase pass onto an adsorption bed formed by a potassium-exchanged Y zeolite, which is preventively saturated with desorbent vapors. According to the invention the desorbent used is isopropylbenzene in vapor phase. This facilitates the quick separation of the pure components, with the exception of the presence of desorbent. The process according to this invention is quicker in comparison to traditional ones. It requires the use of lower charges of desorbent and allows the separation of single pure components of the mixtures. It especially improves the paraxylene separation in higher concentrations with respect to the desorbent.

Abstract: This invention concerns a new product consisting of TiO.sub.2 particles having pigmentary granulometric and morphological characteristics. It includes a chemically reactive coating consisting of a mixture of oxides and oxychlorides selected from the group consisting of Al.sub.2 O.sub.3 and AlOCl; SiO.sub.2 and SiOCl.sub.2 ; and ZrO.sub.2 and ZrOCl.sub.2.The particles of reactive TiO.sub.2 product are prepared as follows: the surface of the TiO.sub.2 particles is activated by thermally treating the particles in a moving bed with an anhydrous gas at 400.degree.-600.degree. C. The particles are then made to react in a moving bed at 350.degree. C. to 600.degree. C., in the presence of a carrier gas, with an inorganic chloride selected from the group consisting of AlCl.sub.3, SiCl.sub.4 and ZrCl.sub.4.This new product is useful, for instance, in TiO.sub.2 pigments coated with organic molecules which provide an affinity for the vehicles of paints.

Abstract: A process for the separation of metaxylene from aromatic C.sub.8 hydrocarbons, particularly from ethylbenzene and paraxylene, wherein a first phase is provided in which the mixture of aromatic hydrocarbons is selectively adsorbed, in vapor phase, into a catalytic bed consisting of zeolite of the Y type, preliminarily exchanged with potassium, and in a second phase a desorption is effected with a suitable solvent. The process, carried out at a temperature of 150.degree. to 200.degree. C. and preferably at atmospherical pressure, permits the recovery of metaxylene, substantially pure and at a concentration much higher than that of the starting mixture.