Acetic acid extraction plant

Figure 8.12 Furfural/acetic acid extraction plant to treat the condensate from Lenzing s sulfite pulping process (extraction efficiency -80-90%). ...

Figure 52. Specific Steam Consumption of Acetic Acid Recovery Plants as based on Extraction with Ethyl Acetate.

Reference Bakerbond Application Note Bi-006 Extraction of Indole-3-Acetic Acid from Plant Tissue and the reference by Liu and Tillberg (1983) (see Suggested Reading, Chapter 1). 

The results in Table 28 indicate that for lettuces, at any rate, the level at which phytotoxic effects begin to appear is very much lower than this, at around 20 ppm acetic acid>extractable cadmium. We can therefore conclude that levels greater than 20 ppm are generally undesirable for crop production in that there is some possibility of phytotoxicity. The precise biochemical mechanism within the plant associated with cadmium toxicity still appears to be the subject of controversy, but phytotoxicity has been ascribed to competition of cadmium with zinc for active sites without functional substitution [312]. 

This work is a valuable demonstration of the ease with which this element can enter plants as a first stage in food chains and, from the point of view of human or animal health, any enhancement of soil cadmium levels above the low background level naturally present in topsoil (around 0.13 ppm acetic acid-extractable cadmium) is highly undesirable. 

Comparatively little is known about the relationship between plant uptake of nickel and chromium and the available levels of these elements in the soil, as measured by acetic acid extraction. It has been known for a long time, however, that nickel is quite phytotoxic. In the last century, Haselhoff [314] demonstrated that in nutrient solutions, levels of nickel in the range, 2-40 ppm, are toxic to beans and maize. More recently, it has been reported [315, 108]... 

Anhydrous Acetic Acid. In the manufacture of acetic acid by direct oxidation of a petroleum-based feedstock, solvent extraction has been used to separate acetic acid [64-19-7] from the aqueous reaction Hquor containing significant quantities of formic and propionic acids. Isoamyl acetate [123-92-2] is used as solvent to extract nearly all the acetic acid, and some water, from the aqueous feed (236). The extract is then dehydrated by azeotropic distillation using isoamyl acetate as water entrainer (see DISTILLATION, AZEOTROPIC AND EXTRACTIVE). It is claimed that the extraction step in this process affords substantial savings in plant capital investment and operating cost (see Acetic acid and derivatives). A detailed description of various extraction processes is available (237). 

The latest of three ethylene recovery plants was started in 1991. Sasol sold almost 300,000 t of ethylene in 1992. Sasol also produces polypropylene at Secunda from propylene produced at Sasol Two. In 1992 Sasol started constmction of a linear alpha olefin plant at Secunda to be completed in 1994 (40). Initial production is expected to be 100,000 t/yr pentene and hexene. Sasol also has a project under constmction to extract and purify krypton and xenon from the air separation plants at Sasol Two. Other potential new products under consideration at Sasol are acrylonitrile, acetic acid, acetates, and alkylamines. 

In a similar appHcation, Cape Industries has announced its intention to commission a solvent extraction plant to recover acetic acid from an effluent generated at its dimethyl terephthalate [120-61-6] faciHty (Wilmington, North Carolina) (44,45). The plant was commissioned in Eebmary 1995. In this case, the solvent will be CYANEX 923 extractant [100786-00-3], CYANEX 923 is also a phosphine oxide, but unlike TOPO is a Hquid and can be used without a diluent (46,47). This has the benefit of reducing plant size, capital, and operating costs. 

Extraction of Sodium Channel Blockers. A review of published reports shows that methods for purification of sodium channel blockers from bacterial cultures are similar to techniques for isolation of TTX and STX from pufferfish and dinoflagellates (30, 31, 38, 39). Typically, cell pellets of bacterial cultures are extracted with hot 0.1% acetic acid, the resulting supernatant ultra-filtered, lyo-philized, and reconstituted in a minimal volume of 0.1% acetic acid. Culture media can also be extracted for TTX by a similar procedure (Ji). Both cell and supernatant extracts are analyzed further by gel filtration chromatography and other biological, chemical, and immunological methods. Few reports describe purification schemes that include extraction of control samples of bacteriological media (e.g., broths and agars) which may be derived from marine plant and animal tissues. 

Ke and Regier [71] have described a direct potentiometric determination of fluoride in seawater after extraction with 8-hydroxyquinoline. This procedure was applied to samples of seawater, fluoridated tap-water, well-water, and effluent from a phosphate reduction plant. Interfering metals, e.g., calcium, magnesium, iron, and aluminium were removed by extraction into a solution of 8-hydroxyquinoline in 2-butoxyethanol-chloroform after addition of glycine-sodium hydroxide buffer solution (pH 10.5 to 10.8). A buffer solution (sodium nitrate-l,2-diamino-cyclohexane-N,N,N. AT-tetra-acetic acid-acetic acid pH 5.5) was then added to adjust the total ionic strength and the fluoride ions were determined by means of a solid membrane fluoride-selective electrode (Orion, model 94-09). Results were in close agreement with and more reproducible than those obtained after distillation [72]. Omission of the extraction led to lower results. Four determinations can be made in one hour. 

Two typical acid extractants are the Bray (which has two forms, both of which are acidic) and the Mehlich-3. The Bray extractant is a dilute solution of hydrochloric acid and ammonium fluoride [11], The Mehlich-3 extractant is a dilute solution of acetic and nitric acids and also contains ammonium nitrate and EDTA [11], Both are designed to extract soluble, exchangeable, and easily dissolved nutrients, particularly phosphate. While the Bray extractant is designed to extract plant available phosphorus, the Mehlich-3 extractant also extracts potassium [10-12],... 

It is important to keep in mind that any extraction of organic matter from soil will include both naturally occurring organic matter and organic contaminants. Separating the two at some later stage of analysis is thus an essential analytical step. For example, extraction of soil with hexane or dichloromethane will extract both l,l,l-trichloro-2,2-di(4-dicholorphenyl)ethane (DDT), a contaminant, and octadecanoic acid, a natural fatty acid. Also, the herbicide 2,4-dichlorophenoxy acetic acid, a contaminant, and indole-3-acetic acid, a natural plant hormone, are both extracted by water (see Figure 12.3). These... 

Two-dimensional techniques are usually employed if both phospho-glycerides and glycolipids are present, but it is possible to resolve members of both classes using a diisobutylketone-acetic acid-water mixture (40 25 5). A solvent composed of acetone, acetic acid and water (100 2 1) will separate the mono- and di-galactosyldiglycerides, which are particularly abundant in plant extracts, from phosphoglycerides, which remain at the origin. 

Normal-phase TLC using a silica stationary phase was employed for the optimization of the separation of flavonoid content of Matricariae flos (Chamomilla recutita L. Rauschert). Air-dried and powdered plant material was extracted by refluxing for 10 min with methanol. The suspension was filtered, evaporated and the residue was redissolved in methanol. The mobile phases included in the experiments were 1 = ethyl acetate-methylethylketone-formic acid-water (50 30 10 10, v/v) 2 = ethyl acetate-methanol-water (75 15 10 v/v) 3 = ethyl acetate-formic acid-water (80 10 10, v/v) 4 = ethyl acetate-formic acid-water (100 20 30, v/v) 5 = ethyl acetate-formic acid-acetic acid-water (100 11 11 27, v/v) 6 = n-butanol-acetic acid-water (66 17 17, v/v) 7 = ethyl acetate-methanol-formic acid-water (75 10 5 10, v/v) 8 = ethyl acetate-acetic acid-water (80 10 10, v/v). Development was carried out in the linear ascending mode at... 

Exposure to acetaldehyde may occur in its production, and in the production of acetic acid and various other chemical agents. It is a metabolite of sugars and ethanol in humans and has been detected in plant extracts, tobacco smoke, engine exliaust, ambient and indoor air, and in water. 

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