High-grade market

Outside of the United States, there are six primary producers in China, France, Mexico, Morocco, South Africa, and Spain. Mines in Newfoundland, Canada, were closed in 1990. Both Mexico and South Africa have lost market share to China which has high grade, low cost fluorspar. China is expected to dominate world markets because reserves are vast and production cost is low. Table 3 (2) shows a Hst of world producers by country of fluorspar in the early 1990s. 

P.R.223 used to have some commercial importance before it was withdrawn from the market. The pigment produces a bluish red shade, bluer even than P.R.170. Its main market was in high grade industrial finishes. Good lightfastness and durability in full shades and the fact that it met certain specifications made it suitable for use on public transportation vehicles. However, the pigment is not fast to overpainting. 

P.R.255 is recommended for high grade lead-free industrial finishes, especially automotive O.E.M. finishes. The commercially available grade tends to flocculate in many formulations. Additives to improve the fastness to flocculation are available on the market. The rheological behavior of finishes is characterized by an distinct thixotropy. This can cause problems at the production of mill pastes. P.R.255 is also of interest for the use in tinting systems for decorative paints. 

The manufacture of phosphorus-derived chemicals is almost entirely based on the production of elemental phosphorus from mined phosphate rock. Ferrophosphorus, widely used in the metallurgical industries, is a direct byproduct of the phosphorus production process. In the United States, over 85% of elemental phosphorus production is used to manufacture high-grade phosphoric acid by the furnace or dry process as opposed to the wet process that converts phosphate rock directly into low-grade phosphoric acid. The remainder of the elemental phosphorus is either marketed directly or converted into phosphoms chemicals. The furnace-grade phosphoric acid is marketed directly, mostly to the food and fertilizer industries. Finally, phosphoric acid is employed to manufacture sodium tripolyphosphate, which is used in detergents and for water treatment, and calcium phosphate, which is used in foods and animal feeds. 

Commercial and industrial possibilities for a high-grade fire-resistive paint are unlimited. Such a paint would find a definite and desirable market in every type of occupancy, from the modest home through the largest factories and warehouses. 

To date, all commercial plants for separation and concentration of CO2 use chemical absorption with a monoethanolamine solvent. This solvent was developed over 60 years ago to remove acid gases, such as CO2 and H2S, from natural gas streams. Monoethanolamine absorption is popular for the existing markets for high-purity CO2, because it produces a very high-grade product. The process has also been used to remove CO2 from flue gases, but it had to be modified... 

After treatment to cause the polymerization of undesirable contaminants the high grade phthalic anhydride is vacuum distilled to yield the commercial product. This product is usually passed through a flake machine to produce phthalic anhydride flakes in which form about 80 per cent of the material is marketed. The flaked form lias considerable advantage over the needle crystal fonn since its bulk density is much higher and any discoloration is more readily detected. 

Attention is called to the fact that the nonaromatics are predominantly cyclic in nature—methylcyclopentadiene being the non-aromatic moiety normally present in the greatest concentration. Reduction of the cyclic olefins and diolefins yields naphthenes rather than paraffins. As a result, sharp separations in the extraction unit becomes more difficult. This is particularly a problem in the C8 range when the individual isomers are to be separated for high grade chemical markets. 

After the conquest of the second oil crisis, the trend of the automotive market turned and headed from low fuel consumption vehicles to high-grade and high-performance vehicles. As a result, the lean burn system with the limiting... 

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