Aluminum price

Aluminum prices have historically been more stable than other nonferrous metals. Beginning iu the 1970s, however, aluminum prices have fluctuated as shown iu Table 13 (30). These fluctuations reflect increased energy costs as well as increased costs of raw materials. Improvements in production processes as well as a rebalancing of demand and supply are expected to stabilize aluminum prices in the future. 

Shipment, Storage, and Price. Butynediol, 35% solution, is available in tank cars, tank trailers, and dmms. Stainless steel, nickel, aluminum, glass, and various plastic and epoxy or phenoHc liners have ak been found satisfactory. Rubber hose is suitable for transferring. The solution is nonflammable and freezes at about —5°C. 

Shipment, Stora.ge, ndPrice. Tank cars and tank trailers, selected to prevent color formation, are of aluminum or stainless steel, or lined with epoxy or phenoHc resins dmms are lined with phenoHc resins. Flexible stainless steel hose is used for transfer. Because of butanediol s high freezing point (about 20°C) tank car coil heaters are provided. The U.S. Hst price for bulk quantities in 1991 was about 2.18/kg, but heavy discounting was prevalent for large contracts. 

The Beckstead-Derr-Price model (Fig. 1) considers both the gas-phase and condensed-phase reactions. It assumes heat release from the condensed phase, an oxidizer flame, a primary diffusion flame between the fuel and oxidizer decomposition products, and a final diffusion flame between the fuel decomposition products and the products of the oxidizer flame. Examination of the physical phenomena reveals an irregular surface on top of the unheated bulk of the propellant that consists of the binder undergoing pyrolysis, decomposing oxidizer particles, and an agglomeration of metallic particles. The oxidizer and fuel decomposition products mix and react exothermically in the three-dimensional zone above the surface for a distance that depends on the propellant composition, its microstmcture, and the ambient pressure and gas velocity. If aluminum is present, additional heat is subsequently produced at a comparatively large distance from the surface. Only small aluminum particles ignite and bum close enough to the surface to influence the propellant bum rate. The temperature of the surface is ca 500 to 1000°C compared to ca 300°C for double-base propellants. 

The principal producers of aluminum trifluoride in North America are Alcan, Alcoa, and AUiedSignal. It is also produced in other countries, eg, France, Mexico, Norway, Italy, Tunisia, and Japan. Total worldwide production of aluminum trifluoride in 1990 was 400,000 metric tons and the price was 1100/t. In 1993, because of excess recovery of fluorine values, use of energy efficient smelters, and the worldwide economic climate, the price was down to 750/t. 

Canada, the United States, and South America are the principal exporters of cryoHte and Russia and Europe import cryoHte. Primary producers in North America are Alcan, Alcoa, and Reynolds Aluminum. The 1993 price of recovered-grade cryoHte, which has as impurity, was 400/t, and of... 

Production. Global hydrogen fluoride production capacity in 1992 was estimated to be 875,000 metric tons. An additional 204,000 metric tons was used captively for production of aluminum fluoride. Worldwide capacity is tabulated in Table 5 (38). Pricing for hydrogen fluoride in 1990 was about 1.52/kg (39). 

There is a general relationship between metal price and terrestrial concentration. Metals present at relatively high concentrations, in the earth s cmst, such as iron and aluminum, are the least expensive rare metals such as gold and platinum are the most valuable. This situation has existed for gold and silver valuation for centuries. The amount of silver in the earth s cmst is approximately 20 times that of gold, and the historical price ratio for gold and silver varied between 10 and 16 for over 3000 years. Since 1970 that price ratio has been strongly affected by market forces and investor speculation. 

The concentration of most metals in the earth s cmst is very low, and even for abundant elements such as aluminum and iron, extraction from common rock is not economically feasible. An ore is a metallic deposit from which the metal can be economically extracted. The amount of valuable metal in the ore is the tenor, or ore grade, usually given as the wt % of metal or oxide. Eor precious metals, the tenor is given in grams per metric ton or troy ounces per avoirdupois short ton (2000 pounds). The tenor and the type of metallic compounds are the main characteristics of an ore. The economic feasibihty of ore processing, however, depends also on the nature, location, and size of the deposit the availabihty and cost of a suitable extraction process and the market price of the metal. 

MAO is a relatively expensive chemical its price in 1994 was about 450/kg of 30 wt % MAO solution, but projected to decrease to about 200/kg (28). Continuous efforts to replace MAO have resulted in the development of co-catalysts containing mixtures of MAO and trimethyl aluminum (29) as well as new co-catalyst types (30,31). Another approach is to prepare MAO directiy in a polymeriza tion reactor by co-feeding into it trimethyl aluminum and water (32). 

Several industries are highly dependent on cheap electric power. These include the aluminum industry, the Portland cement industry, electrochemical industries such as plating and chlorine production, the glass industry, and the pulp and paper industry. Other industries such as the petrochemical industry, which is highly competitive, depend on low priced power. About two-thirds of the cost of producing ammonia is electrical cost. 

Economic Aspects. The North American demand for anhydrous aluminum chloride, estimated to be from 25,000 to 30,000 metric tons per year (9), is divided among the appHcations shown in Figure 2. In 1984 the anhydrous aluminum chloride demand was estimated at 40,000 tons in Western Europe and 9,000 tons in Japan (10). Pricing is heavily dependent on the cost of aluminum metal. The deHvered price of aluminum chloride during the first quarter of 1989 ranged from 0.32/kg for bulk tmddoads to 0.35/kg for small dmms. The North American demand for this catalyst has remained relatively constant over the last 20 years (10). 

Table 4. Annual U.S. Prices for Aluminum Sulfate, Dollars per Metric Ton ...

Ammonium sulfamate is also produced and commercially available in Japan. It is packed in 25-kg net weight paper bags and 500-kg resinous dexible containers. The tmddoad price (fob Japan) is 1.5— 3/kg. Other sulfamates, eg, nickel sulfamate and aluminum sulfamate, are commercially available. The primary salts manufactured from sulfamic acid in the United States are the ammonium and nickel sulfamates. These salts of sulfamic acid are used mainly in electroplating. 

The price of natural citral from Utsea cubeba in 1995 was 17.60—18.70/kg and the price of terpene-based synthetic citral was for 6.60—8.80/kg (69). Higher grades of synthetic citral are available for flavor and fragrance uses and price largely depends on the quaUty and quantity purchased. Shipment of citral is usually made in lined dmms, pails, or aluminum cans. 

The main criteria in the selection of aluminum and its alloys for chemical plants are corrosion resistance, ease of fabrication and price. High-quality aluminum grades are used for chemical and process plant applications. 

Th ere has also been a huge improvement m the value of today s mountain bikes. A mountain bike in the 300 to 500 price range typically has a suspension fork and aluminum frame that would have made It a 1,500 bike a decade earlier. The 800 dual-suspension bike of 2000 far outclasses the early 1990s 2,500 offering. 

This expression seemed to correlate the data of Anderson (A5) for non-aluminized propellants, but did not work for aluminized propellants. In later work, Sehgal (S2) has studied the aluminum effect in greater detail. He reports that the effect of aluminum appears to cause incomplete combustion. Price (P10) has reported essentially the same observation. Beckstead derived an expression between the frequency of the oscillations and the L of the combustion chamber. The resulting equations were then shown to correlate experimental data. 

Nineteen bone samples were prepared for analysis of the trace elements strontium (Sr), rubidium (Rb), and zinc (Zn). The outer surface of each bone was removed with an aluminum oxide sanding wheel attached to a Dremel tool and the bone was soaked overnight in a weak acetic acid solution (Krueger and Sullivan 1984, Price et al. 1992). After rinsing to neutrality, the bone was dried then crushed in a mill. Bone powder was dry ashed in a muffle furnace at 700°C for 18 hours. Bone ash was pressed into pellets for analysis by x-ray fluorescence spectrometry. Analyses were carried out in the Department of Geology, University of Calgary. 

Twenty-five years after its discovery, aluminum was a precious metal. Then a French chemist developed procedures for reducing aluminum compounds using sodium metal. The price of the metal dropped 100-fold. Even so, in 1885 aluminum was a semiprecious metal used for esoteric purposes such as a prince s baby rattle and the cap for the Washington Monument. 

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