Clays activities

Clays, activated Clay treatment C1CH2CHC1CH20H C1CH2CHOHCH3 C1CH2CHOHCH2C1 1990 Clean Air Act Clean Air Act... 

Phosphoric acid esters having a low content of arsenic can be obtained by treating with 0.1-10% adsorbents such as activated clay, active carbon, alumina, and silica gel to decrease the arsenic content. Thus, 100 parts lauryl phosphate containing 10.3 ppm As and 2 parts activated clay were mixed at 60-70°C for 2 h and filtered to give lauryl phosphate only containing 0.6 ppm As [28]. 

Good results were obtained with (R)-0-acryloylpantolactone (4) in which the dienophile was incorporated with a smaller chiral auxiliary. Some results are reported in Table 4.4, where the cycloadditions catalyzed by Zn(II)-, Fe(II)- and Ti(IV)-K-10 exchanged montmorillonite calcined at 120 °C and 550 °C are compared with those that were not catalyzed and with TiCU- and EtAlCh-catalyzed reactions. Among the metal-clays activated, the Ti(IV)-K-10 was the best catalyst with high conversion and acceptable enantioselectivity obtained after 2 h. 

Abstract The aim of this work was to study the simultaneous effect of amount of clay, activation temperature, contact time, pH, and size of the adsorbent on the retention of oil-grease thermally activated illite by adsorption. The values obtained for the percentage of oil-grease removed ranged from 93.87% for 110°C up to 66.73% for 900°C. The adsorption experiment showed surface that the stronger heat treatment the most effective adsorption of oil-grease. 

Few controlled trials have been conducted with adsorbents (clays, activated charcoal and binding resins) but they may have value. 

Specific rate coefficients (related to unit amount of acid centres) were approximately the same for solid catalysts as well as for HC1 [474]. However, when a montmorillonite clay activated by adsorption of protons on its surface was used as the catalyst in ethyl acetate hydrolysis [475], a higher specific rate coefficient (about 1.8 times at 25°C) was found for the reaction catalysed by adsorbed protons than by dissolved acid, this result being explained by the authors by an increase of activation entropy in the former case. 

Clay Activation. The clay is heated to about 700 °C to destabilize the kaolinite structure by removing hydroxyl ions as water. This can be either a batch process with the clay in crucibles in a directly fired kiln, or a continuous process in a tunnel kiln, rotary kiln, or other furnace. 

Refining involves the purification of triglyceride to remove impurities (phosphatides, polyethylene, chlorophyll, heavy metals, off-odors, color bodies) by a combination of acid/alkali washing, clay/activated silica bleaching, deodorization, and hydrogenation steps. 

Theng, B. K. G. 1982. Clay-activated organic reactions. In International Clay Conference 1981. Developments in Sedimentology, ed. H. van Olphen and F. Veniale 35 197-238. Amsterdam Elsevier. 

Removal or elimination of mycotoxins. Since most of the mycotoxin burden in contaminated commodities is localized to a relatively small number or seeds or kernels [reviewed in Dickens, 200], removal of these contaminated seeds/kemels is effective in detoxifying the commodity. Methods currently used include (a) physical separation by identification and removal of damaged seeds, mechanical or electronic sorting, flotation and density separation of damaged or contaminated seeds (b) removal by filtration and adsorption onto filter pads, clays, activated charcoal (c) removal of the toxin by milling processes and (d) removal of the mycotoxin by solvent extraction. 

Figure 2. Clay activation by acid dissolution and cation replacement. (This figure is avaiiabie in full color at http //www.mrw.interscience.wiley.com/biofp.)...

For the refiner trying to mitigate the problem of spontaneous combustion, probably the two most important parameters to control are as follows (1) spent filter cake temperature and (2) oil content. Although the actual temperature marking the onset of second-stage charring will vary from plant to plant depending on type of oil and clay activity, the most important point is that spontaneous combustion should not occur if the spent filter cake temperature can be sufficiently lowered before exposure to the atmosphere. Obviously, water addition is one way to lower temperature and this approach is probably the simplest and most reliable method. 

Proper selection of crosslinking system, for example a low sulfur and thiuram accelerated formulation and choice of mineral fillers like clay, activated calcium carbonates, etc., can increase appreciably the maximum service temperature of the rubber. Combination with good heat resistant antioxidant system is capable of increasing the typical service temperature of natural rubber from around 70 °C to 100 °C and sometimes above this for intermittent exposure. 

CF3S03H phosphonitrilic chlorides such as (Cl3PN(PCl2N) PCl3)+PCl-6 strong bases such as KOH, NaOH, and (CH3)4NOH as well as amines, amine salts of carboxylic acids, ion exchange resin, and clays activated with mineral acids. One of the most efficient and extensively used in industry is the catalytic system based on phosphonitrilic chlorides (70—72). 

Edible oils are not bleached chemically because the color reduction occurs because of oxidizing reactions that have an undesirable effect on the flavor and oxidative stability of the oil (Sipos Szuhaj, 1996). The effective agents for edible-oil bleaching are natural clays, activated earths, carbon, and synthetic silicates (see detailed descriptions... 

SiOi-AljOs Cracking catalysts Activated clays Activated alumina (Aloroo)... 

Since the catalytic properties can not be explained directly by means of electronic properties, it is appropriate to introduce another catalyst concept. In this case, the acid/base concept is suitable. Well-known catalysts with insulator properties are AI2O3, aluminosilicates, Si02/Mg0, silica gels, phosphates such as AIPO4, and special clays activated by chemical treatment. All these catalysts have acid centers on their surface. 

Finally, some other parameters may be used for soil classification for specific purposes, namely dry density, clay activity, mineralogical nature, saturation index, permeability, compressibility index (Cd, swelling index and carbonate index. 

Clays Activated charcoal Flocculation and adsorption Total of 0.5 mg/1 >... 

Another, similar, application of activated carbons is in the treatment of edible oils and fats to remove undesirable components. Here, they are used in conjunction with certain bleaching clays. Activated carbon are also used in treating wines and spirits to remove any traces of fusel oil. In the production of brandies, they are used to remove undesirable flavours and to reduce the amount of aldehydes in the raw distillate. In the case of beers, activated carbons are used to improve their colour, and to remove flavours attributed to phenol and colouring matter. 

The Si—O—Si chain will thereafter break and rearrange. The most frequently used acidic catalysts are sulphuric acid, montmorillonite clays activated with sulphuric acid, other mineral acids, alkane- and perfluoroalkane-sulphonic acids, FeCl3 and other Lewis acids. Sulphuric acid is most effective at 84% acid to 8% oleum. Whereas sulphuric acid is used at a concentration of 1 to 2%, the perflu-oroalkanesulfphonic acids are active at concentrations of only 0.1 weight %. With the latter catalysts, temperatures of 25-50 C are used. 

Studies of the adsorption and desorption of 432 D-glucose oxidase on clays Active immobilized enzyme investigations 410 of the effects of hydrogen peroxide and the flow rate on the enzymic activity Active immobilized enzyme 414... 

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