Abstract: A continuous online process for rejuvenating whole stream of contaminated lean sulfolane in an extraction system is provided. A rejuvenator is installed in the solvent: circulation loop to remove the contaminants continuously to keep the solvent clean, effective and less corrosive. The rejuvenator includes a high pressure vessel with a removable cover and a round rack with vertical stainless steel tubes fitted in the high pressure vessel. A magnetic bar is placed in each stainless steel tube. A screen cylinder is installed outside the ring of stainless steel tubes. As the contaminated sulfolane is passed through the rejuvenator, the rejuvenator picks up contaminants. The rejuvenator can be dissembled to remove the contaminants periodically. The rejuvenator is simple in construction, reliable in operation, and low in operation and maintenance costs. With this rejuvenator, the extraction system operates at high efficiency and high capacity without the dreaded corrosion.

Abstract: 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.

Abstract: A dual-bed catalytic distillation tower has a catalytic column having an upper catalytic bed filled with low temperature dehydration catalysts and a lower catalytic bed filled with high temperature dehydration catalysts. When using the dual-bed catalytic distillation tower, the feeding may be fed to the tower at the top of the upper catalytic bed, between the upper and lower catalytic beds, or at the bottom of the lower catalytic bed for dehydration to obtain DME. The dual-bed catalytic distillation tower has the advantage of flexible set-up depending on various feedings such as anhydrous or crude methanol and on different grades of DME to be obtained.

Abstract: A novel design of filters for removing iron rust particulates and other polymeric sludge from refinery and chemical process streams that are paramagnetic in nature is provided. The performance of these filters is greatly enhanced by the presence of the magnetic field induced by magnets. Basically, the filter comprises a high-pressure vessel with means to support the plurality of magnets in the form of bars or plates that are encased in stainless steel tubes or columns. Filters with various configurations are disclosed for accommodating the removal of contaminants from the process streams of different industries, with high efficiency for contaminants removal, simple construction, low operational and maintenance costs, and low hazardous operation.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A dual-bed catalytic distillation tower has a catalytic column having an upper catalytic bed filled with low temperature dehydration catalysts and a lower catalytic bed filled with high temperature dehydration catalysts. When using the dual-bed catalytic distillation tower, the feeding may be fed to the tower at the top of the upper catalytic bed, between the upper and lower catalytic beds, or at the bottom of the lower catalytic bed for dehydration to obtain DME. The dual-bed catalytic distillation tower has the advantage of flexible set-up depending on various feedings such as anhydrous or crude methanol and on different grades of DME to be obtained.

Abstract: 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.

Abstract: Non-basic and non-acidic homogeneous catalysts organo-metallic compound of the formula: M(OCH3)x wherein M is B, Na, Mg, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Al, Sn, Sb, Mo, Ag, and Cd and x is an integer from 2, 3 or 4 can catalyze transesterification of oils and fats having high free fatty acid content and with an acid number from 0.5 to 20, into biodiesel. B(OCH3)3 and Ge(OCH3)4, having low boiling points, are easily recovered from the biodiesel and glycerol phases and recycled for reuse. Continuous biodiesel production with the novel homogenous catalysts is achieved without the complicated and troublesome steps attendant with conventional processes using base or acid homogeneous catalyst. The high purity biodiesel is produced without acid-base neutralization, water wash, filtration, and solid disposal steps for removing the spent catalyst from the product streams associated with prior techniques.

Abstract: A dual-bed catalytic distillation tower has a catalytic column having an upper catalytic bed filled with low temperature dehydration catalysts and a lower catalytic bed filled with high temperature dehydration catalysts. When using the dual-bed catalytic distillation tower, the feed may be fed to the tower at the top of the upper catalytic bed, between the upper and lower catalytic beds, or at the bottom of the lower catalytic bed for dehydration to obtain DME. The dual-bed catalytic distillation tower has the advantage of flexible set up depending on various feeds, such as anhydrous or crude methanol and on different grades of DME to be obtained.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A continuous online process for rejuvenating whole stream of contaminated lean sulfolane in an extraction system is provided. A rejuvenator is installed in the solvent circulation loop to remove the contaminants continuously to keep the solvent clean, effective and less corrosive. The rejuvenator includes a high pressure vessel with a removable cover and a round rack with vertical stainless steel tubes fitted in the high pressure vessel. A magnetic bar is placed in each stainless steel tube. A screen cylinder is installed outside the ring of stainless steel tubes. As the contaminated sulfolane is passed through the rejuvenator, the rejuvenator picks up contaminants. The rejuvenator can be dissembled to remove the contaminants periodically. The rejuvenator is simple in construction, reliable in operation, and low in operation and maintenance costs. With this rejuvenator, the extraction system operates at high efficiency and high capacity without the dreaded corrosion.

Abstract: A continuous epoxidation process for the production of high purity propylene oxide by the reaction of propylene with an oxidant that is a per-acid, such as peracetic acid (PAA), in a reactive distillation (RD) column. The RD column provides excellent heat integration and temperature control, and the process has the advantage of lower investment cost for capital equipment. The process operates at mild temperatures and pressures. A ferric acetylacetonate homogeneous catalyst and/or stabilizer may be included as part of the PAA feed to the process to increase PAA conversion and selectivity to propylene oxide. A pre-reactor can be incorporated upsteam of the RD column to increase the residence time at lower temperatures to enhance productivity.