Amt International Inc.

Cpc Corporation, Taiwan

Cpc Corporation

Glitsch, Inc.

Kuang-Yeu Wu

Tzong-Bin Lin

Fu-Ming Lee

Hung-Chung Shen

Jyh-Haur Hwang

Tsung-Min Chiu

Adam T Lee

Karl Tze-Tang Chuang

Larry W Burton

Jeng-Cheng Lee

Ji-Young Jang

Yu-Ming Wu

Yung-Sheng Ho

Lindsey Vuong

Tung-Hsiung Kuo

Karl T Chuang

Cheng-Tsung Hong

Pai-Yu Polly Chiang

Han-Tjen Jan

Fong-Cheng Su

Po-Sung Cheng

Tai-Ping Chang

Zong-Ying Chen

Gilbert K Chen

Gary Wayne Gage

Francis William Lemon

Edward K Liu

Fred G Tahmassi

Ming-Mou Yang

Ming-Hsung Liu

Yuan-Fu Sun

Ciputra Jap

Jeffrey Tsung-Min Chiu

Benjamin Poi Chen

Recovering a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a lean solvent stream containing the selective solvent, measurable amounts of heavy aromatic HCs, and polymeric materials that are generated in an extractive distillation (ED) or liquid-liquid extraction (LLE) process. At least a portion of the lean solvent stream is contact in a solvent clean-up zone with a slip stream from the HC feed stream of the ED or LLE process or an external stream. The HC feed stream, such as pyrolysis gasoline or reformate, contains significant amounts of benzene and at least 50% polar (aromatic) HCs and serves as a displacement agent to remove the heavy HCs and polymeric material from the lean solvent stream. A magnetic filter can be used to remove the paramagnetic contaminants from the lean solvent.

Regeneration of selective solvents for extractive processes

A carboxylic acid e.g. acetic acid, is recovered from an aqueous feed stream containing the corresponding ester, an alcohol and a small amount of water by catalytically dehydrating the alcohol to the corresponding ether and water, and reacting the water with the ester to generate a liquid carboxylic acid rich product stream. The acid is recovered by distillation. In a second embodiment, additional alcohol and/or water are co-fed with the feed or fed directly to a catalytic distillation column, resulting in a liquid bottom product stream of substantially pure acetic acid and a top distillate stream of substantially pure ether.

Process for recovery of a carboxylic acid from a feed stream containing the corresponding ester

Various substantially styrene-, methylstyrene- and ethylbenzene-free C6-C9 aromatic hydrocarbon blends are produced from a hydrocarbon feed stream containing C5-C9 aromatic hydrocarbons including styrene, methylstyrene and sulphur compounds by first separating the stream into a distillate containing C5-C7 hydrocarbons, and a bottoms fraction containing C8 and C9 hydrocarbons; and converting the styrene and methylstyrene to their corresponding ethers by reacting with a C1-C3 lower alcohol in the presence of a selective acidic etherification catalyst. The effluent may be sent to a gasoline pool for blending or the effluent is separated by distillation into an ether stream and either a C8 or a C8-C9 aromatic hydrocarbon rich stream. The C5-C7 distillate is hydrogenated.

Process for producing styrene-, methylstyrene- and ethylbenzene-free C6-C9 aromatic hydrocarbon blends

Recovering high purity benzene from hydrocarbon feedstock containing aromatics and non-aromatics is implemented by simple and low-cost modifications to conventional extractive distillation columns (EDCs). Methyl cyclohexane (MCH) that is generated through non-selective hydrogenation of toluene in hydrodesulfurization (HDS) units is a major contaminant in benzene production. To meet MCH specifications, often times the extractive distillation (ED) process for recovering purified benzene is operated with excessive benzene loss to the overhead raffinate stream, producing a lower quality non-aromatic product. Novel techniques (1) remove operational constrictions of the HDS unit on MCH production, thus lengthening the catalyst life and (2) allow the EDC to drive essentially any amount of MCH away from the bottom benzene product without concerns with benzene loss to the overhead raffinate stream and (3) recover benzene from the overhead raffinate stream to upgrade the quality of non-aromatic product and increase the benzene product recovery.

Extractive distillation process for benzene recovery

A magnetic filter employs a magnetic core assembly that incorporates a plurality of exchangeable holder sleeves, each enclosing permanent magnets. Neither the sleeves nor magnetic bars are mechanically fixed to the filter housing. The magnet bars and holder sleeves are individually accessible. The number of holder sleeves in the magnetic core assembly is flexible. The magnetic filter in equipped with a screen that partially encloses the elongated holder sleeves to treat streams that contain degradation sludge, iron containing particles or flakes, and non-magnetic polymeric materials. In operation, a feed stream initially contacts the magnetic core assembly where paramagnetic contaminants become deposited onto the exterior surface of the holder sleeves under direct influence of strong magnetic field generated by the magnet bars. The mesh screen cylinder subsequently captures non-magnetic and weakly magnetic contaminants of a certain size before the cleaned stream exits the magnetic filter.

Magnetic filter for refining and chemical industries

The invention disclosed relates to a process for refining a hydrocarbon feed to make substantially styrene-free C6-C8 aromatic hydrocarbons (BTX). The hydrocarbon feed, for example, unhydrotreated pyrolysis gasoline, is distilled to make a BTX rich stream containing styrene which is fractionated to separate C6 and C7 hydrocarbons from C8 hydrocarbons including styrene. Styrene in the C8 hydrocarbons reacts in the presence of a selective etherification catalyst with a C1-C3 lower alkyl alcohol to form the corresponding styrene ether, which is then separated by distillation into a styrene ether stream and a C8 hydrocarbons rich stream. The C8 hydrocarbons rich stream is then re-mixed with the C6 and C7 hydrocarbons, and sent to hydrogenation reactors to remove sulphur and olefinic hydrocarbons to form substantially styrene-free BTX.

Separating styrene from C6-C8 aromatic hydrocarbons

A method for cross connecting the lean solvent supply lines between the liquid liquid extraction (LLE) and the extractive distillation (ED) processes thereby using the LLE column as the outlet for removing accumulated heavy hydrocarbons (HCs) and polymeric materials from the solvent loop of both processes to maintain their solvent performance. The unique capabilities of the LLE column in rejecting heavy HCs from the solvent into a raffinate product stream that leaves the system enable the removal of the accumulated heavy HCs and polymeric materials from the closed solvent loop of the ED process when their lean solvent loop are cross connected. Cross connection requires minimum equipment change. In the revamped system, the solvent recovery column (SRC) in LLE process supplies lean solvent for the extractive distillation column while the SRC of the ED process supplies lean solvent for LLE column.

Methods for removing heavy hydrocarbons from extractive solvents

Solvent regeneration to recover a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a solvent-rich stream containing selective solvent, heavy HCs, and polymeric materials (PMs) generated from reactions among thermally decomposed or oxidized solvent, heavy HCs, and additives is provided. A combination of displacement agent and associated co-displacement agent squeezes out the heavy HCs and PMs from the extractive solvent within a solvent clean-up zone. Simultaneously, a filter equipped with a magnetic field is positioned in a lean solvent circulation line to remove paramagnetic contaminants. The presence of the co-displacement agent significantly enhances the capability of the displacement agent in removing the heavy HCs and PMs from the extractive solvent. As a result, the solvent regeneration system operates under milder conditions and minimizes or eliminates the need for including a high temperature, energy intensive and difficult-to-operate thermal solvent regenerator.

Extraction process with novel solvent regeneration methods

A two-stage sealed magnetic filter continuously removes magnetic and non-magnetic contaminants from liquid process streams. Elongated non-magnetic holder sleeves encasing magnet bars attract magnetic contaminants while a screen cylinder captures non-magnetic contaminants. The magnet bars are accessible without having to open the interior of the housing to the environment. Thus, during maintenance, removing the magnet bars from the holder sleeves releases the magnetic contaminants that have adhered to the holder sleeves into the screen cylinder which partially encloses the holder sleeves. Contaminants are flushed out of the magnetic filter without exposing workers to potentially hazardous substances. Polymeric sludge occluded with iron compounds can be effectively removed from streams in refineries and chemical plants. The iron compounds are formed from carbon steel which is prevalent in plant machinery and that corrodes in the presence of acidic contaminants.

Sealed magnetic filter for hazardous operations and easy clean service

A method for recovering acetic acid from an aqueous feed stream containing acetic acid and, in particular, a stream generated during terephthalic acid production includes feeding a water-rich feed stream to a liquid-liquid extraction column, which includes a guard bed near the top thereof for conversion of alcohol within the feed stream by reaction with acetic acid to the corresponding ester, and removing residual water from acetic acid in an azeotropic distillation column by feeding water-poor feed streams from the extraction column to the distillation column at a height at which the mixture has a similar water concentration. The liquid-liquid extraction column produces an extract of an extraction solvent and acetic acid which is sent to the azeotropic distillation column to separate residual water and acetic acid.

Method for recovery of acetic acid from an aqueous solution thereof

A process and apparatus is provided for reduction of dissolved oxygen content in seawater from about 8 ppm in the feed seawater to about 10 ppb or less. Significant advantages are achieved by: use of a separator in horizontal alignment to provide high gas-liquid contacting area for separation and de-entrainment within the separator, thereby providing higher throughput; and heating seawater to at least 30&#xb0; C. and up to 60&#xb0; C., so as to enhance removal of oxygen from seawater; use of once-through fuel gas as stripping gas and its subsequent combustion for heating the seawater provides for high efficiency and reduction of fouling. The combination of these features allows the amount of residual oxygen in deoxygenated seawater to be reduced to below 10 ppb and as low as 2 ppb.

Process and apparatus for removal of oxygen from seawater

A highly effective liquid-liquid extraction process to remove nitrogen compounds and especially basic nitrogen compounds from aromatic light petroleum oils with excellent recovery employs de-ionized water, which can be acidified, as the extractive solvent. The product is an aromatic hydrocarbon with ultra-low amounts of nitrogen poisons that can deactivate acidic catalysts. The extracted oils are suitable feedstock for the subsequent catalytic processes that are promoted with the high performance solid catalysts, which are extremely sensitive to nitrogen poison.

Process for producing petroleum oils with ultra-low nitrogen content

The invention disclosed is an apparatus and method for the recovery of acetic acid, azeotropic agent, extraction agent, re-usable water and other reaction products such as p-toluic acid, from an aqueous stream generated during a terephthalic acid production process, having superior energy efficiency and reduced water consumption. The apparatus of the invention includes: an azeotropic distillation column to remove water from acetic acid, a pair of mother liquor extraction columns sequentially connected in series for primary recovery of extraction solvent and other organics, an azeotropic agent stripper for recovery of azeotropic agent and a post-separation solvent stripper distillation column for further separation of the aqueous bottoms stream from said extraction columns into a volatiles stream comprising mainly organics with a very low amount of water and a liquid stream comprising water containing very low amounts of organics, each stream being sufficiently pure that it can be recycled for reuse in the purification of crude terephthalic acid.

System and method for reduction of water consumption in purified terephthalic acid production

The invention disclosed relates to an apparatus and method for recovering acetic acid from an aqueous feed stream containing acetic acid, in particular a stream generated during terephthalic acid production. The apparatus includes: a liquid-liquid extraction column to which water-rich feed streams are fed, having a guard bed situated near the top and within the extraction column for conversion by reaction with acetic acid of alcohol within the mixture to the corresponding ester; and an azeotropic distillation column to remove residual water from acetic acid, to which water-poor feed streams are fed directly at a height of the azeotropic distillation column at which the mixture therein has a similar water concentration. The liquid-liquid extraction column produces an extract comprising an extraction solvent and acetic acid which is sent to the azeotropic distillation column to separate residual water and acetic acid.

Apparatus and method for recovery of acetic acid from an aqueous solution thereof

An improved solvent regeneration system for extractive distillation and liquid-liquid extraction processes capable of effectively removing heavy hydrocarbons and polymeric materials that otherwise develop in a closed solvent loop. The improved process employs a light hydrocarbon displacement agent, which is at least partially soluble in the solvent to squeeze the heavy hydrocarbons and polymeric materials out of the solvent, with virtually no additional energy requirement. It has been demonstrated that the light non-aromatic hydrocarbons in the raffinate stream generated from the extractive distillation or the liquid-liquid extractive process for aromatic hydrocarbons recovery can displace not only the heavy non-aromatic hydrocarbons but also the heavy aromatic hydrocarbons from the extractive solvent, especially when the aromatic hydrocarbons in the solvent are in the Cmolecular weight range.

Growing community of inventors

Plano, TX, United States of America

Kuang-Yeu Wu