Abstract: The present invention relates to a continuous method for treating a crude phenol stream comprising methylbenzofuran and hydroxyacetone by passing the crude phenol stream through at least two reactors connected in series the reactors containing an acidic ion exchange resin, whereby the temperature in successive reactors decreases in flow direction of the phenol stream so that the temperature in the first reactor in flow direction of the phenol stream is between 100° C. and 200° C. and the temperature in the last reactor in flow direction of the phenol stream is between 50° C. and 90° C. without a thermal separation step between any of two successive reactors and to the use of this method in a process for making phenol.

Abstract: The present invention provides a continuous process for recovering acetone from a waste stream from an acetone purification stage. The waste stream contains mesityl oxide and optionally acetone. The process for recovering acetone includes separating the waste stream in a separating device at least in one stream containing mesityl oxide and optionally a further stream containing acetone, then concentrating mesityl oxide in the mesityl oxide containing stream, and finally recycling the concentrated mesityl oxide stream to the separating device and bringing it into contact with a basic or acidic aqueous medium or with an acidic catalyst in the presence of water whereby mesityl oxide is at least partially hydrolyzed to acetone.

Abstract: The present invention relates to method for producing phenol which includes: a) oxidizing cumene to form an oxidation product containing cumene hydroperoxide; b) cleaving the oxidation product using an acidic catalyst to form a cleavage product containing phenol, acetone and impurities; c) neutralizing and washing the cleavage product with a basic aqueous medium to obtain a neutralized cleavage product; d) separating the neutralized cleavage product by at least one distillation step into at least a phenol containing fraction and an aqueous fraction comprising hydroxyacetone; e) treating the aqueous fraction with an oxidizing agent in presence of a base to obtain a basic aqueous medium reduced in hydroxyacetone; f) recycling at least a portion of the basic aqueous medium to the neutralizing and washing step c); and g) recovering phenol from the phenol containing fraction obtained in step d).

Abstract: The present invention relates to a continuous method for treating a crude phenol stream comprising methylbenzofuran and hydroxyacetone by passing the crude phenol stream through at least two reactors connected in series the reactors containing an acidic ion exchange resin, whereby the temperature in successive reactors decreases in flow direction of the phenol stream so that the temperature in the first reactor in flow direction of the phenol stream is between 100° C. and 200° C. and the temperature in the last reactor in flow direction of the phenol stream is between 50° C. and 90° C. without a thermal separation step between any of two successive reactors and to the use of this method in a process for making phenol.

Abstract: The present invention provides a continuous process for recovering acetone from a waste stream from an acetone purification stage, whereas said waste stream comprises mesityl oxide and optionally acetone by separating the waste stream in a separating device at least in one stream comprising mesityl oxide and optionally a further stream comprising acetone, by than concentrating mesityl oxide in the mesityl oxide containing stream and finally by recycling the concentrated mesityl oxide stream to the separating device and bringing it into contact with a basic or acidic aqueous medium or with an acidic catalyst in the presence of water whereby mesityl oxide is at least partially hydrolyzed to acetone.

Abstract: The cleavage product from the acid-catalyzed cleavage of cumene hydroperoxide into phenol and acetone is subjected to thermal after-treatment by a process, which comprises heating the cleavage product in a reactor, wherein the heat supplied for the thermal treatment is the heat generated by at least one exothermic reaction which occurs in the reactor. The exothermic reaction which proceeds in the cleavage product is preferably the cleavage of cumene hydroperoxide.

Abstract: Impurities are removed from phenol by a process, comprising: first treating phenols containing impurities with at least one acid catalyst which converts the impurities into compounds which can be separated from phenol; separating the acid treated phenol from the compounds; and treating the distilled phenol a second time with at least one acid catalyst; thereby effectively removing the impurities from phenol.

Abstract: The invention provides a device, method (400,500,600), and system (100) to improve compression efficiency when coding audio for bitrate scalability. It includes at least one of an encoder and a decoder and is applicable when utilizing perceptual coding for an upper bitrate. The encoder includes a hybrid psychoacoustic modeling unit, coupled to receive lowband audio and diffband audio, for determining psychoacoustic data, and a quantizer control and zero-flagging unit, coupled to receive psychoacoustic data and diffband audio, for determining explicit quantizer stepsize parameters and at least one of: 1) implicit quantizer stepsize parameters and 2) implicit zero-flags.

Abstract: The transportation and storage of phenol is enhanced by additions of up to 70% by weight of acetone to liquid phenol.