Acid capacity

Because of projected nylon-6,6 growth of 4—10% (167) per year in the Far East, several companies have announced plans for that area. A Rhc ne-Poulenc/Oriental Chemical Industry joint venture (Kofran) announced a 1991 startup for a 50,000-t/yr plant in Onsan, South Korea (168,169). Asahi announced plans for a 15,000-t/yr expansion of adipic acid capacity at their Nobeoka complex in late 1989, accompanied by a 60,000-t/yr cyclohexanol plant at Mizushima based on their new cyclohexene hydration technology (170). In early 1990 the Du Pont Company announced plans for a major nylon-6,6 complex for Singapore, including a 90,000-t/yr adipic acid plant due to start up in 1993 (167). Plans or negotiations for other adipic acid capacity in the area include Formosa Plastics (Taiwan) (171) and BASF-Hyundai Petrochemical (South Korea) (167). Adipic acid is a truly worldwide... 

Table 6. Hydrofluoric Acid Capacity in North America ...

This process may be competitive with butane oxidation (see Hydrocarbon oxidation) which produces a spectmm of products (138), but neither process is competitive with the process from synthesis gas practiced by Monsanto (139) and BASF (140) which have been used in 90% of the new acetic acid capacity added since 1975. 

Saure-bindungsvermogen, n. power to combine with acids, acid capacity, -bottich, m. acid vat. -braun, n. acid brown, -bromid,... 

Direct titration [119,120] In order to know the number of exchangeable hydrogen ions at different dissociation stayes, various salts of weak acids were used. Data observed in Table 8 shows an increase in the exchange capacity with an increase in the pH of the solution, indicating the presence of weak acid capacity [118]. 

Standard test for hydrolytic stability. The hydrolytic stability of the chlorinated resins was determined by the following test procedure. An acid digestion autoclave having a volume of 125 ml is charged with 40 ml of resin and 28 ml of deionized water. The bomb is sealed and transferred into an oven, pre-heated to 200 °C. The test is continued for 24 hours. The bomb is removed and cooled to ambient temperature. The liquid is separated from the resin and the chlorine content analyzed while the resin is washed thoroughly and its acid capacity is determined as described in section 5. The test results are shown in Table 2. 

Determination of the Exchange Capacity. The acid capacity of the resins is determined by the following procedure. Approximately 10-12 g of a wet resin was placed in a beaker and dried overnight at 110 °C. The beaker was then... 

Calcium can be used as an indicator for selective carbonate dissolution. Its concentration in the extracts is limited either by its content in the carbonate phase (at low pHs and/or low carbonate content of the soil) or by the acid capacity of the extracting solution (at higher pHs and/or higher carbonate content in the soil). The interplay of these factors is clearly shown in Fig. 4.2. 

The contents of trace elements extracted by the buffer solutions depend upon the solution s acid capacity in dissolving carbonate from soils. Trace elements dissolved by the buffer solution increased with decreasing pH of the buffer solution (Table 4.3). Release of trace elements by the buffer solutions at pH 6.0 was much smaller from calcareous soils with more than 30% of CaCC>3. The dissolution of trace elements by the buffers paralleled with the dissolution of Ca and Mg. The correlation coefficients between Ca and trace elements were as follows Cd (0.92), Pb (0.87), Zn (0.90), Ni (0.90), Cr (0.91), V (0.54) and Co (0.70) and between Mg and trace elements were Cd (0.88), Pb (0.80), Zn (0.79), Ni (0.87), Cr (0.58), V (0.69) and Co (0.80), (all with n = 32). 

A sample of phosphonic acid resin Diaion CRP200 in wet Na+ form was kindly provided from Mitsubishi Chemical Co. Ltd. This wet resin sample was dried in vacuum, and then the resin with particle sizes of 60 - 32 mesh was selected by meshing. The selected resin was conditioned by treatment with 1 M HC1, water, 2 M NaOH, water, 1 M HC1, and water in successive. Finally, thus, the resin was changed into H+ form. The phosphorus content and acid capacity of the selected resin in the H+ form were measured according to the reported methods and were 4.6 mmol/g and 8.8 meq/g, respectively. Wet volume of the resin was 2.6 ml/g. Hereafter, this is abbreviated as CRP200 for simplicity. 

Exchangers Phosphorus content Sulfur content Acid capacity... 

Add groups are introduced by sulfonation, e.g., with sulfuric add. If all the benzene rings are monosulfonated, an acid capacity of the order of 5 mmol gca, 1 should be obtained. The sulfonic acid sites are situated in the easily accessible macropores, and also inside the gel-type microspheres [26]. 

In 1970, the first rhodium-based acetic acid production unit went on stream in Texas City, with an annual capacity of 150 000 tons. Since that time, the Monsanto process has formed the basis for most new capacities such that, in 1991, it was responsible for about 55% of the total acetic acid capacity worldwide. In 1986, B.P. Chemicals acquired the exclusive licensing rights to the Monsanto process, and 10 years later announced its own carbonylation iridium/ruthenium/iodide system [7, 8] (Cativa ). Details of this process, from the viewpoint of its reactivity and mechanism, are provided later in this chapter. A comparison will also be made between the iridium- and rhodium-based processes. Notably, as the iridium system is more stable than its rhodium counterpart, a lower water content can be adopted which, in turn, leads to higher reaction rates, a reduced formation of byproducts, and a better yield on CO. 

Smelter acid capacity measures are not entirely consistent. Among several possible estimates the two following are given in thousands of short tons of 100% I SOi per annum for 1978 ... 

Obviously, not all smelter acid capacity is utilized and not all SO2 produced is transformed into acid. For copper, lead, and zinc alone, if it is assumed that only 93.5 percent of the sulfur had been removed, metal production in 1976 implied an acid production of 6 million short tons. Actual acid production was 3.2 million short tons. A doubling of acid output due to abatement... 

As seen from the above, conventional uses of methanol cover a wide range of products which in turn find application in a very broad cross-section of industrial and consumer goods. New end uses have continued to develop and spur the growth of methanol production. One such development is the Monsanto low pressure process that carbonylates methanol to acetic acid (6). Essentially all new acetic acid capacity now being installed is based on Monsanto technology. By 1981, eleven plants converting methanol to acetic acid are scheduled to be on stream. At capacity they will consume over 300 million gallons of methanol. 

Acid capacity, mequiv g 0.89 A base titration procedure measures the equivalents of sulfonic acid in the polymer, and uses the measurement to calculate the acid capacity or equivalent weight of the membrane. 

Determination of Total Acid Capacity of a WAC Exchanger on a Dry Weight Basis... 

Acetic acid is a key commodity building block [1], Its most important derivative, vinyl acetate monomer, is the largest and fastest growing outlet for acetic acid. It accounts for an estimated 40 % of the total global acetic acid consumption. The majority of the remaining worldwide acetic acid production is used to manufacture other acetate esters (i.e., cellulose acetates from acetic anhydride and ethyl, propyl, and butyl esters) and monoehloroacetic acid. Acetic acid is also used as a solvent in the manufacture of terephthalic acid [2] (cf. Section 2.8.1.2). Since Monsanto commercially introduced the rhodium- catalyzed carbonylation process Monsanto process ) in 1970, over 90 % of all new acetic acid capacity worldwide is produced by this process [2], Currently, more than 50 % of the annual world acetic acid capacity of 7 million metric tons is derived from the methanol carbonylation process [2]. The low-pressure reaction conditions, the high catalyst activity, and exceptional product selectivity are key factors for the success of this process in the acetic acid industry [13]. 

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