A process and a plant for the preparation of an acqueous solution of urea suitable for use in a SCR process for nitrogen oxides removal, wherein the urea solution from the recovery section of a urea plant is subject to at least one step of evaporation, separating a vapour stream containing water and ammonia, and obtaining a concentrated and substantially ammonia-free solution, and said concentrated solution is diluted to the concentration of urea suitable for use in the SCR process.

A catalytic system comprising a REDOX catalyst and a porous polymeric matrix wherein the porous polymeric matrix has pores with a size from 1 to 1000 nm and it is covalently functionalized with functional groups R.sub.1 or, alternatively, with functional groups R.sub.1 and R.sub.2. The REDOX catalyst comprises an isoalloxazine moiety which has one or more functional groups R.sub.3; R.sub.1 and R.sub.2 are capable of forming non-covalent reversible interactions with R.sub.3; R.sub.1 and R.sub.2 are in a molar concentration excess with respect to the molar concentration of the REDOX catalyst; and R.sub.1 and R.sub.1 are electron donor or electron acceptor groups having a REDOX potential between +2.70 to ?2.5 V as determined by cyclic voltammetry using an Ag/AgCl electrode as reference.

An organic-inorganic composite catalyst wherein the organic-inorganic composite catalyst includes a porous carbonaceous particle, a first compound; and a metal oxide particle, wherein the first compound and the metal oxide particle are supported on the porous carbonaceous particle, the first compound contains a polar functional group, an anion, or a combination thereof, the metal oxide is represented by the formula M.sub.aO.sub.b, wherein 0<a?4, 0<b?5, and M is a metal of Groups 2 to 16 of the Periodic Table of Elements, or a combination thereof, and the organic-inorganic composite catalyst is configured to remove a second compound from an unpurified air flow including the second compound.

The subject invention pertains to a method of halogenating phenols, yielding a range of halogenated phenols with enantiomeric ratio of up to 99.5:0.5. In certain embodiments, the subject invention pertains to a method of asymmetric halogenation of bisphenol, yielding a range of chiral bisphenol ligands. The novel chiral bisphenols are potent privileged catalyst cores that can be applied to the preparation of ligands for various catalytic asymmetric reactions. The catalyst library can easily be accessed because late-stage modification of the scaffold can readily be executed through cross-coupling of the halogen handles on the bisphenols.

A process is provided for the selective oligomerization of C.sub.5 to C.sub.20 alpha-olefins to produce polyalphaolefin oligomers with a molecular weight distribution that is suitable for use in lubricant base oils.

The subject invention pertains to a method of halogenating phenols, yielding a range of halogenated phenols with enantiomeric ratio of up to 99.5:0.5. In certain embodiments, the subject invention pertains to a method of asymmetric halogenation of bisphenol, yielding a range of chiral bisphenol ligands. The novel chiral bisphenols are potent privileged catalyst cores that can be applied to the preparation of ligands for various catalytic asymmetric reactions. The catalyst library can easily be accessed because late-stage modification of the scaffold can readily be executed through cross-coupling of the halogen handles on the bisphenols.

A method of catalytic oxidation of a lignite using oxygen as an oxidant at atmospheric pressure is provided. The method includes the following steps, pulverizing the lignite to 200-mesh or less; drying the pulverized lignite at a temperature of 80 C. in vacuum for 10 h; weighing 0.5 g of the dried lignite and sequentially adding 10 ml of acetic acid, 0.5 mmol of a catalyst and 0.15-0.25 mmol of a cocatalyst into a round-bottom flask filled with the oxygen, keeping oxygen pressure at 0.1 MPa, reacting at a temperature of 80-120 C. for 4-12 h; using oxygen as the oxidant to catalytically oxidize the reacted lignite at an atmospheric pressure of 0.1 MPa; filtering after the reaction is finished; decompressing the filtrate to remove the acetic acid, adding a small amount of ethyl acetate to dissolve, and using an excess CH.sub.2N.sub.2/ether solution to esterify for 10 h at room temperature; and analyzing the esterified product through a gas chromatography-mass spectrometer.

Disclosed is a method of catalytic oxidation of lignite using oxygen as an oxidant at atmospheric pressure, belonging to a method of mild oxidation of lignite. The method is used to mildly oxidize the lignite using the oxygen as the oxidant under the action of a nitroxide radical catalyst and a metal salt or metal oxide cocatalyst; the process comprises the following steps: pulverizing the lignite to 200 meshes or less, drying a pulverized coal sample at a temperature of 80 C. in vacuum for 10 h, weighing 0.5 g of the treated coal sample, sequentially adding 10 ml of acetic acid, 0.5 mmol of a catalyst and 0.15 to 0.25 mmol of a cocatalyst into a round-bottom flask, connecting a tee joint to an upper orifice of a condenser pipe, replacing oxygen in vacuum for three times so that the round-bottom flask is filled with the oxygen, keeping oxygen pressure at 0.1 MPa, reacting at a temperature of 80 C. to 120 C. for 4 to 12 h; filtering after the reaction is finished; decompressing a filtrate to remove the acetic acid, adding a small amount of ethyl acetate to dissolve, then using an excess CH.sub.2N.sub.2/ether solution to esterify for 10 h at room temperature, using 0.45 m filter paper to filter, and analyzing an esterified product through a gas chromatography-mass spectrometer. The method has the advantages of using the oxygen as the oxidant, having low price, having no toxicity, and achieving environmental protection and mild conditions.

This invention disclosure relates to a process to make flexible open cell polyurethane foam with optimum mechanical properties and lowest chemical emissions. Using the selection of tertiary amine catalysts together with a group of carboxylic acids according to this disclosure can produce foam products with optimum properties and lowest chemical emanations.

The present disclosure relates to ionic liquid-solvent complex comprising cation and anion and are prepared in the presence of a solvent. The present disclosure also relates to the process for preparing ionic liquid-solvent complex and also to a process for producing linear alkyl benzene using the ionic liquid-solvent complex. The present disclosure also relates to various applications of the ionic liquid-solvent complex.