Adsorbents attapulgite

Intestinal adsorbents attapulgite, activated bismuth subsalicylate... 

The foremnner of the modern methods of asphalt fractionation was first described in 1916 (50) and the procedure was later modified by use of fuller s earth (attapulgite [1337-76-4]) to remove the resinous components (51). Further modifications and preferences led to the development of a variety of fractionation methods (52—58). Thus, because of the nature and varieties of fractions possible and the large number of precipitants or adsorbents, a great number of methods can be devised to determine the composition of asphalts (5,6,44,45). Fractions have also been separated by thermal diffusion (59), by dialysis (60), by electrolytic methods (61), and by repeated solvent fractionations (62,63). 

Attapulgite adsorbs excess fluid in the stool with few adverse effects. Calcium polycarbophil is a hydrophilic polyacrylic resin that also works as an adsorbent, binding about 60 times its weight in water and leading to the formation of a gel that enhances stool formation. Neither attapulgite nor polycarbophil is systemically absorbed. Both products are effective in reducing fluid in the stool but can also adsorb nutrients and other medications. Their administration should be separated from other oral medications by 2 to 3 hours. Psyllium and methylcellulose products may also be used to reduce fluid in the stool and relieve chronic diarrhea. 

DL Sorby. Effect of adsorbents on drug absorption. I. Modification of promazine absorption by activated attapulgite and activated charcoal. J Pharm Sci 54 677-683, 1965. 

Based on their molecular properties as well as the properties of the solvent, each inorganic or organic contaminant exhibits an adsorption isotherm that corresponds to one of the isotherm classifications just described. Figure 5.1 illustrates these isotherms for different organic contaminants, adsorbed either from water or hexane solution on kaolinite, attapulgite, montmorillonite, and a red Mediterranean soil (Yaron et al. 1996). These isotherms may be used to deduce the adsorption mechanism. 

The amount of adsorbed chemical is controlled by both properties of the chemical and of the clay material. The clay saturating cation is a major factor affecting the adsorption of the organophosphorus pesticide. The adsorption isotherm of parathion from an aqueous solution onto montmorillonite saturated with various cations (Fig. 8.32), shows that the sorption sequence (Al > Na > Ca ) is not in agreement with any of the ionic series based on ionic properties. This shows that, in parathion-montmoriUonite interactions in aqueous suspension, such factors as clay dispersion, steric effects, and hydration shells are dominant in the sorption process. In general, organophosphorus adsorption on clays is described by the Freundhch equation, and the values for parathion sorption are 3 for Ca +-kaoUnite, 125 for Ca -montmorillonite, and 145 for Ca -attapulgite. 

The hydration status of the clay or earth material may affect the adsorption capacity of nonpolar (or slightly polar) toxic chemicals. Continuing with parathion as a case study, Fig. 8.33 shows the increase adsorbed parathion on attapulgite from a hexane solution, as the adsorbed water on the clay surface decreases. This behavior may be explained by the competition for adsorption sites between the polar water and the slightly polar parathion. Possibly, however, the reduction in adsorption due to the presence of water is caused by the increased time required for parathion molecules to diffuse through the water film to the adsorption sites. 

In a dry attapulgite-parathion-hexane system, parathion molecules compete effectively with nonpolar hexane molecules for the adsorption sites. In partially hydrated systems, parathion molecules cannot replace the strongly adsorbed water molecules, so that parathion adsorption occurs only on water-free surfaces and a decrease in adsorption per total surface area may be observed. Infrared studies lead to an... 

Locally-acting are all agents that decrease stimulation of receptors in the GI tract. A viscous formulation of local anesthetics such as lidocaine increases the threshold of receptor-activity to vomiting. Adsorbents and mucosa protective agents like kaolin and pectin, activated charcoal, bismuth subsalicylate, attapulgite and cholestyramine have similar effects. Cola Syrup and phosphorylated carbohydrate can decrease GI muscle spasm with consequently less input into the vomiting center. 

The heat curves, themselves, are informative. The kaolin-based pellet catalyst has a few more active sites then attapulgite, but its site activity decreases rapidly and to values only about 3 kcal./mole above the heat of liquefaction of the liquid at maximum coverage. Obviously, a distinction cannot be made between physical adsorption and chemisorption for some of the amine adsorbed at full coverage on the cracking catalyst. On the other hand, attapulgite has a much narrower distribution of adsorption energies, and the lowest heats are about double the heat of liquefaction of butyl amine. Therefore, it appears safe to conclude that the amount remaining after evacuation at 25° is chemisorbed. 

The surface coverage d is the ratio of the amine remaining adsorbed after evacuation at temperature T to the total adsorbed after saturation and evacuation at 25° to an ultimate vacuum between 10 and 10 mm. Hg. The maximum adsorption at 25° on attapulgite and the catalyst sample is large and covers about one-half of the total available area of the solids if 20.8 A, is used as the cross-sectional area of adsorbed butyl amine. 

Adsorbents such as kaolin, pectin, or attapulgite are administered to take up and hold harmful substances such as bacteria and toxins in the intestinal lumen.44 Theoretically, these adsorbents sequester the harmful products that cause the diarrhea. These products are used frequently in minor diarrhea, although there is some doubt as to whether they really help decrease stool production and water loss. 

Attapulgite can adsorb water. It should be stored in an airtight container in a cool, dry, location. 

Attapulgite is widely used as an adsorbent in solid dosage forms. Colloidal clays (such as attapulgite) absorb considerable amounts of water to form gels and in concentrations of 2-5% w/v usually form oil-in-water emulsions. Activated attapulgite, which is attapulgite that has been carefully heated to increase its absorptive capacity, is used therapeutically as an adjunct in the management of diarrhea. 

The adsorbents used in antidiarrhoeals are kaolin, attapulgite and bismuth salicylate. 

Attapulgite A, LMV, RVM, Basco Salt Mud, Econosorb, Fertogel, Gel B, Gel 420-P, Gel 540-P, Gel 601-P, High Yield Attapulgite, Milfines, Milsorb, Milsorb-CG, Supper Gel B Non-Metals, Inc., Affiliate of The China Non-Metallic Minerals, Tucson, AZ, USA Attapulgite clay for paint, adsorbent, drilling mud, and fertilizer... 

In order to avoid these extremely dangerous phenomena, methods of treatment of PO with adsorbents (active carbon, charcoal, attapulgite, diatomaceous earth) were devised. By the treatment at room temperature of PO with these adsorbents (0.1-1% adsorbent in liquid PO), after a short contact time of about 15 minutes the high MW polyether is almost quantitatively retained by adsorption. The PO resulting after the filtration of the solid adsorbent is practically free of high MW polymers, and the polyethers obtained with the treated PO can be used to manufacture resilient flexible foams which will not collapse, with high rise and free of blow hole formation. 

Refinex . [Floridin] RVM attapulgite contact adsorbent for reclaimii motm oils. 

S-60RVM. [Floridin] Attapulgite clay absorbent, adsorbent... 

Pharmasorb. [Engelhard] Attapulgite clay adsorbent to phar ceudcals. 

Liu P, Jiang L, Zhu L, Wang A (2014) Novel approach for attapulgite/poly(acrylic acid) (ATP/PAA) nanocomposite microgels as selective adsorbent for Pb(II) ion. React Funct Polym 74 72-80... 

Adsorbents are chemically inert powders that have the ability to adsorb moisture, gasses, toxins, and to some extent, bacteria. Some minerals have found extensive use as adsorbents, such as magnesium aluminum silicate, bentonite, attapulgite, talc, calcium carbonate, and kaolin. The activities of kaolin and calcium carbonate were discussed in a preceding section. 

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