Raw materials economics

This significant difference in projected feedstock price is key to a large raw material economic advantage for butadiene oxycarbonylation technology. Recent softening of worldwide oil prices has resulted in 0.85 per gallon benzene and 0.26 per pound butadiene. Butadiene oxycarbonylation economics based on these feedstock prices are less attractive. It may be well into the year 2000 before decreased oil reserves make a synthesis gas route to adipic acid economically attractive. 

The first case study relates to vinyl chloride monomer (VCM) production and provides an excellent example of how changing raw materials, economics and technology stimulated research and development to develop new routes to this compound. 

Example 2.2 Devise a process from the three reaction paths in Example 2.1 which uses ethylene and chlorine as raw materials and produces no byproducts other than water. Does the process look attractive economically ... 

Considering raw materials costs only, the economic potential (EP) of the process is defined as... 

The economic tradeoffs now become more complex, and a new cost must be added to the tradeoffs. This is a raw material efficiency cost due to byproduct formation. If the PRODUCT formation is kept constant despite varying levels of BYPRODUCT formation, then the cost can be defined to be ... 

Figure 10.7 shows that the tradeoff between separation and net raw materials cost gives an economically optimal recovery. It is possible that significant changes in the degree of recovery can have a significant effect on costs other than those shown in Fig. 10.7 (e.g., reactor costs). If this is the case, then these also must be included in the tradeoffs. 

In most processes, the largest individual cost is raw materials. Raw materials costs and product prices tend to have the largest influence on the economic performance of the process. The value of raw materials and products depends on whether the materials in question are being bought and sold under a contractual arrangement (either within or outside the company) or on the open market (the spot price). Open-market prices can fluctuate considerably with time. Products are normally sold at below open-market price when under a contractual arrangement. 

In the 1980s cost and availabiUty of acetylene have made it an unattractive raw material for acrylate manufacture as compared to propylene, which has been readily available at attractive cost (see Acetylene-DERIVED chemicals). As a consequence, essentially all commercial units based on acetylene, with the exception of BASF s plant at Ludwigshafen, have been shut down. AH new capacity recendy brought on stream or announced for constmction uses the propylene route. Rohm and Haas Co. has developed an alternative method based on aLkoxycarbonylation of ethylene, but has not commercialized it because of the more favorable economics of the propylene route. 

Ethylene Cyanohydrin Process. This process, the fkst for the manufacture of acryhc acid and esters, has been replaced by more economical ones. During World War I, the need for ethylene as an important raw material for the synthesis of ahphatic chemicals led to development of this process (16) in both Germany, in 1927, and the United States, in 1931. 

Because of the high costs of raw materials and the relatively complex synthesis, the 2-cyanoacryhc esters are moderately expensive materials when considered in bulk quantities. Depending on the quantity and the specific ester or formulation involved, the prices for cyanoacryhc ester adhesives can range from approximately 30/kg to over 1000/kg. For these reasons, as weU as several technical factors related to handling and performance, cyanoacryhc ester adhesives are best suited to small bonding apphcations, very often where single drops or small beads are adequate for bonding. In such cases the cost of the adhesive becomes inconsequential compared to the value of the service it performs, and these adhesives become very economical to use. 

The propylene-based process developed by Sohio was able to displace all other commercial production technologies because of its substantial advantage in overall production costs, primarily due to lower raw material costs. Raw material costs less by-product credits account for about 60% of the total acrylonitrile production cost for a world-scale plant. The process has remained economically advantaged over other process technologies since the first commercial plant in 1960 because of the higher acrylonitrile yields resulting from the introduction of improved commercial catalysts. Reported per-pass conversions of propylene to acrylonitrile have increased from about 65% to over 80% (28,68—70). 

Trends in the field of economics are the centralization of the powder fabrication to enable production on a large scale and the manufacture of low quahty anisotropic materials by a much less expensive technology. An example of the latter is the introduction of alignment during pressing of the raw material mixture in the fabrication route of isotropic materials. 

Economics. In contrast to NSP, the high nutrient content of TSP makes shipment of the finished product preferable to shipping of the raw materials. Plants, therefore, are located at or near the rock source. The phosphoric acid used, and the sulfuric acid required for its manufacture, usually are produced at the site of the TSP plant. As in the case of NSP, the cost of raw materials accounts for more than 90% of the total cost. Most of this is the cost of acid. 

Polyethylene. Polyethylene remains the largest volume film and sheet raw material. It is available in a wide range of types, with variations in copolymers, homopolymers, molecular weight, and other factors contributing to a long Hst of resins. Resins are designed specifically for end use, and in addition blends of the various types may be used by processors to optimize properties, processibiUty, and economics. Almost two-thirds of the volume of all polyethylene resins are used in film or sheet appHcations (see Olefin polymers). 

Cost Calculation. The main elements determining production cost are identical for fine chemicals and commodities (see Economic evaluation), a breakdown of production cost is given in Table 2. In multipurpose plants, where different fine chemicals occupying the equipment to different extents are produced during the year, a fair allocation of costs is a more difficult task. The allocation of the product-related costs, such as raw material and utiHties, is relatively easy. It is much more difficult to allocate for capital cost, labor, and maintenance. A simplistic approach is to define a daily rent by dividing the total yearly fixed cost of the plant by the number of production days. But that approach penalizes the simple products using only part of the equipment. 

Economic Market. The spice trade is controlled by many direct elements and responds slowly to supply and demand fluctuations. Resupply depends on growth to plant maturity, which for certain items, such as black pepper or nutmeg, can be several years. The raw material is directly affected by climate, adverse weather conditions, and control of plant diseases and insect and animal pests. Limited agricultural scientific advances are appHed to the cultivation of the botanicals, and there are many grades of product and degrees of quahty caused by different growing or processing conditions, sometimes by unknown factors as well. 

Ethers, such as MTBE and methyl / fZ-amyl ether (TAME) are made by a catalytic process from methanol (qv) and the corresponding isomeric olefin. These ethers have excellent octane values and compete on an economic basis with alkylation for inclusion in gasoline. Another ether, ethyl tert-huty ether (ETBE) is made from ethanol (qv) and isobutylene (see Butylenes). The cost and economic driving forces to use ETBE vs MTBE or TAME ate a function of the raw material costs and any tax incentives that may be provided because of the ethanol that is used to produce it. 

Yellow mercuric oxide may be obtained by precipitation from solutions of practically any water-soluble mercuric salt through the addition of alkah. The most economical are mercuric chloride or nitrate. Although yellow HgO has some medicinal value in ointments and other such preparations, the primary use is as a raw material for other mercury compounds, eg, Millon s ha.se[12529-66-7], Hg2NOH, which is formed by the reaction of aqueous ammonia and yellow mercuric oxide. 

Economic Aspects. To be useful the raw materials must be recoverable at a cost not greater than the cost of similar terrestrial materials. These costs must include transportation to the point of sale. Comparative costs of recovery are strongly influenced by secondary environmental or imputed costs, such as legal costs or compensatory levies. 

Oxidation of Carbohydrates. Oxahc acid is prepared by the oxidation of carbohydrates (7—9), such as glucose, sucrose, starch, dextrin, molasses, etc, with nitric acid (qv). The choice of the carbohydrate raw material depends on availabihty, economics, and process operating characteristics. Among the various raw materials considered, com starch (or starch in general) and sugar are the most commonly available. Eor example, tapioka starch is the Brazihan raw material, and sugar is used in India. 

Synthesis. Exploratory research has produced a wide variety of odorants based on natural stmctures, chemicals analogous to naturals, and synthetic materials derived from available raw materials and economical processing. As in most areas of the chemical industry, the search for new and useful substances is made difficult by the many materials that have been patented and successfully commercialized (4). In the search for new aroma chemicals, many new materials are prepared for screening each year. Chemists who perform this work are involved in a creative exercise that takes its direction from the commercial sector in terms of desirable odor types and specific performance needs. Because of economic limitations, considerations of raw material costs and available processing methods may play a role eady in the exploratory work. 

Economic Aspects. Trimesic acid being a smaH-volume chemical, availabiUty is in polyethylene-lined fiber dmms in 34- and 136-kg quantities. Mesitylene [108-67-8] the raw material, is readily available, and oxidation to trimesic acid presents no problems. The market size is dictated by commercial uses. 

Polyamide and Intermediates, Techcon (U.K.) Ltd., London pubHshed monthly Nylon Intermediates andFiber, PCI— Fibers Raw Materials, West Sussex, U.K. pubHshed monthly World Nylon 6 and 66 Supply and Demand Report, PCI— Fibers Raw Materials, West Sussex, U.K. pubHshed annually Chemical Economic Handbook, Stanford Research Institute, Menlo Park, Calif., pubHshed and updated periodically. 

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