Petrochemical catalysts development

MPC [Mitsui Petrochemical] A continuous process for polymerizing propylene, based on the Ziegler-Natta process, but using a much more active catalyst so that de-ashing (catalyst removal) is not required. The catalyst contains magnesium in addition to titanium successive versions of it have been known as HY-HS (high yield, high stereospecifity), HY-HS II, and T-catalyst. Developed jointly by Mitsui Petrochemical Industries, Japan, and Montedison SpA, Italy, in 1975, and now licensed in 56 plants worldwide. 

As an example of low-temperature catalytic reactions, hydrogenation of unsaturated hydrocarbons is the most important industrial application. Chemical industrial needs are mainly for unsaturated hydrocarbons, which have reactivities that enable polymer or petrochemical product development. All the processes developed for the production of olefins, diolefins, and aromatics give a mixture of unsaturated hydrocarbons, which are not valuable as such further hydrogenations are necessary to obtain usable products for refining and chemical industry. Sulfur is generally considered to be a poison of hydrogenation catalysts. But in the case of hydrodehydrogenation reactions, this compound can also be used as a modifier of selectivity or even, in some cases, as an activator. 

CTO [Coal To Olefins] A general name for processes that convert coal to ethylene and/or propylene, used for making petrochemicals or fuels. Operated in South Africa, using catalysts developed and supplied by Siid-Chemie. 

Different market conditions rendered attractive the use of the process in the reverse direction to produce polymerization grade propene from ethylene and but-2-ene. In this process, but-2-ene can be obtained directly from the C4 fraction of a naphthta cracker or by dimerization of ethylene. In 1985, the Lyondell Petrochemical Co. started to operate a plant at Channelview (Texas, U.S.A.), for the production of 135000 tons of propene per year. In this process, part of the ethylene formed by cracking units of ethane is dimerized to but-2-ene using a homogeneous nickel catalyst developed by Phillips. This but-2-ene reacts with the rest of ethylene, on the classical Phillips catalyst, to produce propene. 

The other important aspect of the development of the succinic acid market is the chemical conversion of succinic acid to other products. Selective and low-cost catalyst development is needed to enable lower-cost economics. The chemistry of succinic acid catalysis has been reviewed by Varadarajan and Miller (1999), and the summary of the various derived products that follow is from that work. Succinic acid can be readily converted into alkyl esters that have uses as industrial solvents and paint removers. Succinic acid, its anhydride or its esters, can be hydrogenated to the product family of 1,4-butanediol however, this conversion has not been as well studied as the hydrogenation of maleic acid or anhydride. A third important product family that can be derived from ammonium succinate, succinimide, or succinic acid is based on 2-pyrroHdinones. They are used for polyvinylpyrrolidone (PVP) production, which has an estimated minimum market value of 150 million per year. Other uses for 2-pyrrolidinones include solvents and plasticizers. The commercial production depends upon petrochemical-based... 

Various catalysts have been used, but now, the preferred one is believed to be a supported palladium/gold alloy catalyst. Developed in 1980 by Lyondell Chemical Technology, formerly Millennium Petrochemicals, and used in their plant in La Porte, TX. See also Vacido. Also a trademark used by LyondellBasell Industries. 

ISOMPLUS A process for isomerizing -butenes to isobutene and -pentane to iso-amylene, using aZSM-5 zeolite catalyst. Developed by CD Tech and Lyondell Petrochemical. One unit was operating in 1996. Used in their Channelview refinery, TX. 

During the same period Universal Oil Products developed olefin polymerization and hydrogenation processes and the Shell Chemical Company became interested in olefin chemistry and petrochemicals. Shell opened its Emeryville, California, research center in 1928 and developed methods for the production of alcohols, ketones, and esters from propylene and butylenes, as well as synthetic chlorohydrins, glycols, and glycerol. Many of these petroleum chemicals were produced in Martinez, California, from 1933 and the use of petrochemical catalysts became established. 

Solid Superacids. Most large-scale petrochemical and chemical industrial processes ate preferably done, whenever possible, over soHd catalysts. SoHd acid systems have been developed with considerably higher acidity than those of acidic oxides. Graphite-intercalated AlCl is an effective sohd Friedel-Crafts catalyst but loses catalytic activity because of partial hydrolysis and leaching of the Lewis acid halide from the graphite. Aluminum chloride can also be complexed to sulfonate polystyrene resins but again the stabiUty of the catalyst is limited. 

Phenol Vi Cyclohexene. In 1989 Mitsui Petrochemicals developed a process in which phenol was produced from cyclohexene. In this process, benzene is partially hydrogenated to cyclohexene in the presence of water and a mthenium-containing catalyst. The cyclohexene then reacts with water to form cyclohexanol or oxygen to form cyclohexanone. The cyclohexanol or cyclohexanone is then dehydrogenated to phenol. No phenol plants have been built employing this process. 

Esterification ofTerephthalicAcid. Esterification of terephthaUc acid is also used to produce dimethyl terephthalate commercially, although the amount made by this process has declined. Imperial Chemical Industries, Eastman Kodak, Amoco, Toray, Mitsubishi, and Mitsui Petrochemical have all developed processes. Esterification (qv) generally uses a large excess of methanol in a Hquid process at 250—300°C. The reaction proceeds rapidly without a catalyst, but metal catalysts such as zinc, molybdenum, antimony, and tin can be used. Conversion to dimethyl terephthalate is limited by equiHbrium, but yields of 96% have been reported (75,76). 

Remarkably, seventy years after Houdry s utilization of the catalytic properties of activated clay and the subsequent development of ci ystalline aluminosilicate catalysts that arc a magnitude more catalytically active, the same fundamental principles remain the basis for the modern manufacture of gasoline, heating oils, and petrochemicals. 

In 1950 the Fischer-Tropsch synthesis was banned in Germany by the allied forces. Sinarol, a high paraffinic kerosene fraction sold by Shell, was used as a substitute. This ban coincided with the rapid development of the European petrochemical industry, and in due time Fischer-Tropsch synthesis applied to the production of paraffins became uneconomic anyway. After the war there was a steady worldwide increase in the demand for surfactants. In order to continually meet the demand for synthetic detergents, the industry was compelled to find a substitute for /z-paraffin. This was achieved by the oligomerization of the propene part of raffinate gases with phosphoric acid catalyst at 200°C and about 20 bars pressure to produce tetrapropene. Tetrapropene was inexpensive, comprising a defined C cut and an olefinic double bond. Instead of the Lewis acid, aluminum chloride, hydrofluoric acid could now be used as a considerably milder, more economical, and easier-to-handle alkylation catalyst [4],... 

Two options are being developed at the moment. The first is to produce 1,2-propanediol (propylene glycol) from glycerol. 1,2-Propanediol has a number of industrial uses, including as a less toxic alternative to ethylene glycol in anti-freeze. Conventionally, 1,2-propanediol is made from a petrochemical feedstock, propylene oxide. The new process uses a combination of a copper-chromite catalyst and reactive distillation. The catalyst operates at a lower temperature and pressure than alternative systems 220°C compared to 260°C and 10 bar compared to 150 bar. The process also produces fewer by-products, and should be cheaper than petrochemical routes at current prices for natural glycerol. The first commercial plant is under construction and the process is being actively licensed to other companies. 

ALMA [Alusuisse maleic anhydride] A process for making maleic anhydride by oxidizing -butane, using a fluid bed reactor and a special organic solvent recovery system. The catalyst contains vanadium and phosphoms on iron oxide. Developed jointly by Alusuisse Italia and ABB Lummus Crest. First licensed to Shin-Daikowa Petrochemical Company, Yokkaichi, Japan, in 1988. The world s largest plant plant was built for Lonza in Ravenna, Italy, in 1994. 

Alpha A process for making aromatic hydrocarbons and LPG from C3-C7 olefins. The catalyst is a metal-modified ZSM-5 zeolite. Developed by Asahi Chemical Industries and Sanyo Petrochemical and used since 1993 at Sanyo s Mitzushima refinery. 

Midforming [Middle-range distillate forming] A process for converting lower olefins to transport fuels. The catalyst is either a ZSM-5-type zeolite in which some of the aluminum has been replaced by iron, or a hetero-poly acid. Developed in the 1980s by the National Chemical Laboratory, Pune, India. To be piloted by Bharat Petrochemical Corporation, Bombay, and Davy Poweigas. 

Spheripol A process for making polypropylene and propylene co-polymers. Homopolymerization is conducted in the liquid phase in a loop tubular reactor co-polymerization is conducted in the gas phase in a fluidized-bed reactor. The catalyst is treated with a special silane. The product is in the form of beads of up to 5 mm in diameter. Developed by Montecatini, Italy, and first licensed by Himont, United States, and Mitsui Petrochemical Industries, Japan. In 1989, 29 licenses had been granted worldwide. Now offered for license by Montell, a joint venture between Montedison and Shell. See also Addipol. 

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