Dutch State Mines

Nylon-4,6 [24936-71-8] introduced as Stanyl by Dutch State Mines, is synthesized from 1,4-tetramethylenediarnine and adipic acid (202). Stanyl has a high melting temperature (295°C), improved chemical resistance, better dimensional stabiUty, and higher modulus than nylon-6 and nylon-6,6 it is therefore highly suited for industrial yam appHcations, including tire cord. 

Dutch State Mines (Stamicarbon). Vapor-phase, catalytic hydrogenation of phenol to cyclohexanone over palladium on alumina, Hcensed by Stamicarbon, the engineering subsidiary of DSM, gives a 95% yield at high conversion plus an additional 3% by dehydrogenation of coproduct cyclohexanol over a copper catalyst. Cyclohexane oxidation, an alternative route to cyclohexanone, is used in the United States and in Asia by DSM. A cyclohexane vapor-cloud explosion occurred in 1975 at a co-owned DSM plant in Flixborough, UK (12) the plant was rebuilt but later closed. In addition to the conventional Raschig process for hydroxylamine, DSM has developed a hydroxylamine phosphate—oxime (HPO) process for cyclohexanone oxime no by-product ammonium sulfate is produced. Catalytic ammonia oxidation is followed by absorption of NO in a buffered aqueous phosphoric acid... 

Economic Aspects. Since the 1970s cinnamaldehyde has been produced in significant quantities by Frit2sche Dodge Olcott (FDO), Haarmaim Reimer (H R), and Dutch State Mines (DSM). However, by the end of 1989 DSM was the only remaining producer for this material. Production statistics are Hsted in Table 3. 

Cyclone Separators Finer feed sohds, from 0.04 to 0.0005 m (1.5 in to 28 mesh), may be treated in dynamic separators of the Dutch State Mines cyclone type (Fig. 19-36). In cyclone separators, the medium and the feed enter the separator together tangentially at the feed inlet (1) the short cyhndiical section (2) carries the central vortex finder (3), which prevents short circuiting within the cyclone. Separation is made in the cone-shaped part of the cyclone (4) by the action of centrifugal and centripetal forces. The heavier portion of the feed leaves the cyclone at the apex opening (5), and the hghter portion leaves at the overflow top orifice (6). 

A wet-process plant maldug cement from shale and hmestoue has been described by Bergstrom [Roc/c Prod., 64—71 (June 1967)]. There are separate facilities for grinding each type of stone. The ball mill operates in closed circuit with a battery of Dutch State Mines screens. Material passing the screens is 85 percent minus 200 mesh. The entire process is extensively instrumented and controlled by computer. Automatic devices sample crushed rock, slurries, and finished product for chemical analysis by X-rav fluorescence. Mill circuit feed rates and water additions are governed by conventional controllers. 

Since the first report of the synthesis of dendrimers twenty years ago [1], there has been a remarkable increase in interest in these fascinating materials. For example, the number of publications relating to dendrimers was about 15 in 1990, but this number increased to 150 in 1995, and 420 in 1997. Until very recently emphasis in this field was placed on the synthesis of new families of dendrimers having novel architectures, but more recently there has been interest in finding technological applications for these materials [2-5]. The pursuit of applications has been greatly accelerated by the recent commercial availability of dendrimers through Dendritech, Inc. (Midland, MI), Dutch State Mines (DSM, The Netherlands), and the Aldrich Chemical Co. (Milwaukee, WI). 

Light-scattering Scholte, Dutch State Mines. d Dow Chem. Corp. 

Thanks are also due to various industry laboratories for furnishing samples and data. In this connection should be mentioned Kon.-Shell Plastics Laboratorium Delft, Dow Chem. Corp. and Dutch State Mines. 

Presently, several equation-based flowsheeting systems exist perhaps the best known of these is SPEED-UP, which continues to be developed at Imperial College by Sargent and Perkins and their students. Now commercially available, its strongest attraction in industry seems to be as a dynamic simulator. TISFLO at Dutch State Mines is also often mentioned in the literature. As a complete flowsheeting system, no equation-based approach is yet very popular. One might wonder why. 

DuPont and Dow use solution polymerization technology to produce LLDPE resins. The process is based on continuous polymerization of ethylene with 1-octene in cyclohexane at about 250°C and 1200 psi. The catalyst is again Ziegler type. Residence time is of the order of several minutes. The catalyst is deactivated by treatment with an alcohol or complexing agent such as acetyl-acetone, and adsorbed on a silaceous adsorbent before stripping the solvent. The Stamicarbon (Dutch State mines) process is similar to the DuPont process, and it uses a short-residence-time solution process for HDPE production. 

Nylon Block Copolymers as Matrix Resin. Monsanto and DSM (Dutch State Mines) have been investigating caj olactam RIM with and without glass reinforcement (31). 

DSM (once called Dutch State Mines) introduced nylon 4,6 (Stanyl) in 1990. It is produced via the condensation reaction between adipic acid and... 

The Dutch State Mines process uses hydroxylamine phosphate oxime (HPO) to carry out the oximation of cyclohexanone. The process sequence is shown in Figure 14. In this process phosphoric acid/ammonium nitrate... 

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