Leaching preparation

Both wool and grain dust samples were capable of stimulating TNF release from rat alveolar macrophages isolated by bronchoalveolar lavage, in a dose-dependent maimer (Brown and Donaldson 1996). Leaches prepared from the dusts contained LPS and also caused TNF release but leachable LPS could not account for the TNF release and it was clear that non-LPS leachable activity was present in the grain dust and that wool dust particles themselves were capable of causing release of TNF. 

The quantitative analysis of the elements in the alloy and the resulting catalysts after leaching at 120 °C is listed in Table 15.12. The results show that the leached prepared samples contain a residual aluminum level of 20 % in weight, while there was 10 % in the commercial catalyst. This indicates that the leaching process of the alloys is important. 

The 2eohtes are prepared as essentially bindedess preformed particles. The kaolin is shaped in the desired form of the finished product and is converted in situ in the pellet by treatment with suitable alkaU hydroxide solutions. Preformed pellets of 2eohte A are prepared by this method. These pellets may be converted by ion exchange to other forms such as molecular sieve Type 5A (1). ZeoHtes of higher Si02/Al202 ratios, eg, 2eohte Y, can be obtained by the same method, when sodium metasiUcate is incorporated in the preshaped pellets, or when acid-leached metakaolin is used. 

R. K. Obedander ia B. E. Leach, A., Aluminas for Catalysis Their Preparation and Properties, Vol. 3, Applied Industrial Catalysis, Academic Press, New York, 1984, pp. 98-102. 

Vanadium powder can be prepared by substituting V2O2 for the V20 as the vanadium source. The heat generated during the reduction of the trioxide is considerably less than for the pentoxide, so that only soHd products are obtained. The powder is recovered from the product by leaching the slag with dilute acid. 

J. E. Netdes, Handbook of Chemical Specialties Textile Fiber Processing, Preparation, and B leaching,] ohxs Wiley Sons, Inc., New York, 1983, pp. 391—457. 

Porosity and Pore Size. The same methods used to determine the porosity and pore si2e distribution of the support generally can be used for the catalyst. However, the values found for the catalyst usually ate different from those of the bare support. Porosity could be increased if a part of the support is leached away during preparation of the catalyst, or, more likely, porosity will be decreased because catalytic materials deposited on the support win occupy a part of the support s pore volume. 

The colorant is prepared by leaching the annatto seeds with an extractant prepared from one or more approved, food-grade materials taken from a hst that includes various solvents, edible vegetable oils and fats, and alkaline aqueous and alcohoHc solutions (46,47). Depending on the use intended, the alkaline extracts are often treated with food-grade acids to precipitate the annatto pigments, which ia turn may or may not be further purified by recrystallization from an approved solvent. Annatto extract is one of the oldest known dyes, used siace antiquity for the coloring of food, textiles, and cosmetics. It has been used ia the United States and Europe for over 100 years as a color additive for butter and cheese (48—50). 

The reaction mixture is filtered. The soHds containing K MnO are leached, filtered, and the filtrate composition adjusted for electrolysis. The soHds are gangue. The Cams Chemical Co. electrolyzes a solution containing 120—150 g/L KOH and 50—60 g/L K MnO. The cells are bipolar (68). The anode side is monel and the cathode mild steel. The cathode consists of small protmsions from the bipolar unit. The base of the cathode is coated with a corrosion-resistant plastic such that the ratio of active cathode area to anode area is about 1 to 140. Cells operate at 1.2—1.4 kA. Anode and cathode current densities are about 85—100 A/m and 13—15 kA/m, respectively. The small cathode areas and large anode areas are used to minimize the reduction of permanganate at the cathode (69). Potassium permanganate is continuously crystallized from cell Hquors. The caustic mother Hquors are evaporated and returned to the cell feed preparation system. 

While certain TSILs have been developed to pull metals into the IL phase, others have been developed to keep metals in an IL phase. The use of metal complexes dissolved in IL for catalytic reactions has been one of the most fruitful areas of IL research to date. LLowever, these systems still have a tendency to leach dissolved catalyst into the co-solvents used to extract the product of the reaction from the ionic liquid. Consequently, Wasserscheid et al. have pioneered the use of TSILs based upon the dissolution into a conventional IL of metal complexes that incorporate charged phosphine ligands in their stmctures [16-18]. These metal complex ions become an integral part of the ionic medium, and remain there when the reaction products arising from their use are extracted into a co-solvent. Certain of the charged phosphine ions that form the basis of this chemistry (e.g., P(m-C6H4S03 Na )3) are commercially available, while others may be prepared by established phosphine synthetic procedures. 

The optimal temperature range for the fluorination process was found to be about 230-290°C. The resulting cake was leached with water. The prepared solution was separated from the precipitate by regular filtration and the separated insoluble precipitate was identified as lithium fluoride, LiF. The solution contained up to 90 g/1 Ta205. Solution acidity was relatively low, with a typical pH = 3-4, and was suitable for the precipitation of potassium heptafluorotantalate, K2TaF7, tantalum hydroxide or further purification by liquid-liquid extraction after appropriate adjustment of the solution acidity [113]. 

The main advantages of the method can be formulated as follows. First, hydrofluoric acid is not needed for the decomposition stage the amount of fluorine required for the raw material decomposition can be calculated and adjusted as closely as possible to the stoichiometry of the interaction. Since the leaching of the fluorinated material is performed with water, a significant fraction of the impurities are precipitated in the form of insoluble compounds that can be separated from the solution, hence the filtrated solution is essentially purified. There is no doubt that solutions prepared in this way can be of consistent concentrations of tantalum and niobium, independent of the initial raw material composition. 

Electrodes that are prepared from acid-leached LT-LiCo, xNix02 compounds (0< x<0.2) show significantly enhanced electrochemical behavior over the parent LT-LiCo1 xNix02 structure. The improved performance has been attributed to the formation of compounds with a composition and cation arrangement close to the ideal Li[B2]04 spinel structure (B = Co, Ni) [62]. These spinel-type structures have cubic symmetry, which is maintained on lithiation the unit cells expand and contract by only 0.2 percent during lithium insertion and extraction. 

An inorganic membrane can be prepared by various methods such as sol-gel, phase separation and leaching.2,3 The sol-gel process is considered the most practical method among those used to prepare inorganic membrane. Sol-gel processing is a simple technology in principle but requires considerable effort to become of practical use. The advantage of this... 

Miscellaneous Identified Inhibitors. 3-Acetyl-6-methoxy-benzaldehyde is present in the leaves of the desert shrub Encelia farinosa. It is apparently leached from the leaves and washed into the soil by rain. Concentrations of approximately 0.5 mg. per gram of dried leaf material have been measured. In sand culture studies, growth of tomato seedlings was inhibited by 50 p.p.m. while 115 p.p.m. reduced growth by 50% (53). A concentration of 250 p.p.m. killed the test plants within one day. The structure was confirmed by synthesis, and the synthetic material was shown to be as active as the natural product (54). Derivatives were also prepared in which a cyano, nitro, or amino group was substituted for the aldehyde moiety. The amino derivative was reported to be the most highly toxic. 

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