Abstract:
The present invention provides a method for the production of purified terephthalic acid crystals in an integrated terephthalic acid – polyester plant comprising the steps of: i) providing a stream of purified terephthalic acid crystals in an aqueous medium; ii) separating the purified terephthalic acid crystals from the aqueous medium in a filtration zone; and iii) washing the purified terephthalic acid crystals with an aqueous wash liquid, characterised in that at least a portion of the aqueous wash liquid is derived from an aqueous condensate liquor from the polyester plant.
Abstract:
The present invention provides method for removing residues from a first process stream comprising an organic solvent, water, a derivative of the organic solvent and the residues, comprising the steps of: i) feeding the first process stream to a solvent stripper comprising a still pot and a stripper column; ii) removing a vapour stream comprising the organic solvent, water and the derivative of the organic solvent from the stripper column; and iii) removing a residue stream from the still pot; characterised in that: the still pot and the stripper column form an integrated unit and the stripper column comprises a plurality of sieve trays. The present invention further provides an apparatus for carrying out the method, and processes for the production of a purified aromatic dicarboxylic acid incorporating the method.
Abstract:
The present invention provides processes and apparatuses for recovering an aromatic monocarboxylic acid from a residue stream in which a first solid extraction is followed by a second extraction.
Abstract:
This document describes biochemical pathways for producing 7-hydroxyheptanoate methyl ester and heptanoic acid heptyl ester using one or more of a fatty acid O-methyltransferase , an alcohol O-acetyltransferase , and a monooxygenase , as well as recombinant hosts expressing one or more of such exogenous enzymes. 7-hydroxyheptanoate methyl esters and heptanoic acid heptyl esters can be enzymatically converted to pimelic acid, 7-aminoheptanoate, 7-hydroxyheptanoate, heptamethylenediamine, or 1,7-heptanediol.
Abstract:
A rotary filter comprising (i) a housing comprising a first wash zone comprising a first wash fluid input zone, a final wash zone comprising a final wash fluid input zone, and one or more intervening wash zone(s) each comprising a wash fluid input zone; (ii) a control head comprising a first wash fluid output zone, a final wash fluid output zone, and one or more intervening wash fluid output zone(s); and (iii) a filter drum positioned within the housing and rotatable about its axis within the housing; and (iv) means to transfer wash fluid in counter-current flow, relative to the direction of rotation of the filter drum, from a wash output zone to a wash input zone of a preceding wash zone; characterised in that the rotary filter is configured to pass wash fluid via the filter drum from a wash fluid input zone (IZ n ) to the wash fluid output zone (OZ n ) of the same wash zone (n) and additionally to the wash fluid output zone of a preceding wash zone.
Abstract:
Disclosed is a method for hydrogenating a dinitrile to form a diamine in the presence of ammonia. A liquid stream including a dinitrile is used to scrub a vapor stream including hydrogen and ammonia. Ammonia is taken up in the liquid effluent from the scrubbing treatment. This liquid effluent stream and the hydrogen-rich scrubbed vapors are recycled to the hydrogenation reaction for converting dinitrile to diamine.
Abstract:
Disclosed is a method for hydrogenating a dinitrile to form a diamine. Also disclosed is a method for preparing a catalyst for this hydrogenation reaction by reducing iron oxide with hydrogen. Heat in a fluid stream involved in the refinement of a crude dinitrile stream is used to provide heat for the hydrogenation of a dinitrile to form a diamine.
Abstract:
Disclosed is a method for hydrogenating a dinitrile to form a diamine. Also disclosed is a method for preparing a catalyst for this hydrogenation reaction by reducing iron oxide with hydrogen. The catalyst ages during the course of making the diamine. An aged catalyst is partially reactivated by abruptly interrupting the flow of feed to reactors.
Abstract:
Process for incorporating additives into a polymer utilizing a polymerization reactor in fluid communication with a primary manifold carrying the liquid polymer. The primary manifold is in fluid communication with at least one secondary manifold comprising an additive injection line. The process produces varied finished polymer products from one continuous polymerization reactor.
Abstract:
A continuous process for producing a nylon salt solution prepared using a liquid partially balanced acid solution enriched in dicarboxylic acid, and in particular adipic acid. The liquid feed is prepared by metering dicarboxylic acid powder, based on weight, from a loss-in-weight feeder to a feeding conduit that transfers the dicarboxylic acid powder into an in-line disperser; feeding a first feed stream of diamine to the in-line disperser to form a dispersion comprising between 32 wt.% and 46 wt.% dicarboxylic acid, between 11 wt.% and 15 wt.% diamine, and between 39 wt.% and 57 wt.% water, and heating the dispersion at temperature between 50C and 60C to form a partially balanced acid solution. A nylon salt solution is prepared from the liquid partially balanced acid solution and continuously withdrawn into a storage tank. The nylon salt solution has a uniform pH and is suitable for producing nylon polymers.