The invention relates to an adsorbent comprising a zeolite-based phase and a non-zeolite-based phase, said adsorbent having: an outer surface area of less than or equal to 30 m.sup.2.Math.g.sup.−1, preferably less than or equal to 20 m.sup.2.Math.g.sup.−1, a zeolite-based phase comprising at least one zeolite of FAU structure of X type, and a pore diameter distribution, determined by mercury intrusion according to standard ASTM D 4284-83 and expressed by the volume distribution dV/d log DHg, in which DHg is the apparent pore diameter and V is the pore volume, the mode of which is between 100 nm and 250 nm, limits inclusive.

The invention also relates to a process for preparing the said adsorbent and to the uses thereof, especially for separating xylene isomers.

The invention relates to an adsorbent comprising a zeolite-based phase and a non-zeolite-based phase, said adsorbent having: an outer surface area of less than or equal to 30 m.sup.2.Math.g.sup.−1, preferably less than or equal to 20 m.sup.2.Math.g.sup.−1, a zeolite-based phase comprising at least one zeolite of FAU structure of X type, and a pore diameter distribution, determined by mercury intrusion according to standard ASTM D 4284-83 and expressed by the volume distribution dV/d log DHg, in which DHg is the apparent pore diameter and V is the pore volume, the mode of which is between 100 nm and 250 nm, limits inclusive.

The invention also relates to a process for preparing the said adsorbent and to the uses thereof, especially for separating xylene isomers.

According to the present invention, there is provided a method of producing a salt, including reacting M.sup.+X.sup.− with YH to generate XH and M.sup.+Y.sup.− and subsequently removing the generated XH to obtain the M.sup.+Y.sup.−.

In the method of producing a salt, M.sup.+X.sup.− is a salt of a cation represented by M.sup.+ and an anion represented by X.sup.−, M.sup.+Y.sup.− is a salt of the cation represented by M.sup.+ and an anion represented by Y.sup.−, XH is a conjugate acid of X.sup.−, YH is a conjugate acid of Y.sup.−, M.sup.+Y.sup.− is a compound that generates an acid upon irradiation with an active ray or a radioactive ray, a pKa of XH is larger than a pKa of YH, and a ClogP value of XH is larger than 2.

The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

The present invention relates to zeolite adsorbents based on agglomerated crystals of zeolite X comprising barium, potassium, sodium and strontium. These adsorbents have applications in the separation of fractions of aromatic C8 isomers and in particular xylenes.

The present invention relates to zeolite adsorbents based on agglomerated crystals of zeolite X comprising barium, potassium, sodium and strontium. These adsorbents have applications in the separation of fractions of aromatic C8 isomers and in particular xylenes.

The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

A process for the preparation of a 2,6-di(C.sub.1-7 alkyl)phenol composition includes reacting phenol and a C.sub.1-7 alkyl alcohol in the presence of a catalyst to form the 2,6-di(C.sub.1-7 alkyl)phenol; and isolating the 2,6-di(C.sub.1-7 alkyl)phenol composition by distillation N using a reflux ratio of greater than or equal to 4.0. The 2,6-di(C.sub.1-7 alkyl)phenol composition includes less than or equal to 0.2 wt % of chain-stopper impurities, based on the total weight of the 2,6-di(C.sub.1-7 alkyl)phenol composition. The 2,6-di(C.sub.1-7 alkyl)phenol composition can be useful for the preparation of poly(phenylene ethers).

A process for the preparation of a 2,6-di(C.sub.1-7 alkyl)phenol composition includes reacting phenol and a C.sub.1-7 alkyl alcohol in the presence of a catalyst to form the 2,6-di(C.sub.1-7 alkyl)phenol; and isolating the 2,6-di(C.sub.1-7 alkyl)phenol composition by distillation N using a reflux ratio of greater than or equal to 4.0. The 2,6-di(C.sub.1-7 alkyl)phenol composition includes less than or equal to 0.2 wt % of chain-stopper impurities, based on the total weight of the 2,6-di(C.sub.1-7 alkyl)phenol composition. The 2,6-di(C.sub.1-7 alkyl)phenol composition can be useful for the preparation of poly(phenylene ethers).

A process for the preparation of a 2,6-di(C.sub.1-7 alkyl)phenol composition includes reacting phenol and a C.sub.1-7 alkyl alcohol in the presence of a catalyst to form the 2,6-di(C.sub.1-7 alkyl)phenol; and isolating the 2,6-di(C.sub.1-7 alkyl)phenol composition by distillation N using a reflux ratio of greater than or equal to 4.0. The 2,6-di(C.sub.1-7 alkyl)phenol composition includes less than or equal to 0.2 wt % of chain-stopper impurities, based on the total weight of the 2,6-di(C.sub.1-7 alkyl)phenol composition. The 2,6-di(C.sub.1-7 alkyl)phenol composition can be useful for the preparation of poly(phenylene ethers).