After Treatments

This eliminates the vapor space but sealing the edge can be a problem. Double seals can help and sometimes a fixed roof is also added above the floating roof to help capture any leaks from the seal. However in this case, the space between the fixed and floating roof now breathes and an inert gas purge of this space would typically be used. The inert gas would be vented to atmosphere after treatment. 

Carbonizable substances (paraffin) NFT 60-134 ASTM D 612 Coloration after treatment in concentrated sulfuric acid... 

Sulfated ash in lubricating oils in greases NF T 60-143 ISO 3987 ASTM D 874 NF T 60-144 ASTM D 128 Weight of residue after treatment of the ash by sulfuric acid and calcination As above... 

The first column removes ethane which, after treatment for storage, may be used as feed for an ethylene plant. The heavier hydrocarbons pass to the next fractionating... 

Fig. X-4. Water contact angle of titania-coated glass after treatment with trimethyloc-tadecylammonium chloride as a function of the number of coating treatments with 1.1% polydibutyl titanate. (From Ref. 51.)...

It was claimed that the Z-form of the allylic acetate 430 was retained in homoallylic ketone 431 obtained by reaction with the potassium enolate of 3-vinylcyclopentanone (429), after treatment with triethylborane[282]. Usually this is not possible. The reaction of a (Z)-allylic chloride with an alkenylaluminum reagent to give 1,4-dienes proceeds with retention of the stereochemistry to a considerable extent when it is carried out at -70 C[283]. 

By refluxing 54 and thioformamide for 16 hr m aqueous acetone solution, the expected compound 55 was obtained (Scheme 25). 55 in acetic medium, after treatment with hydrochloric add and zinc, gives 2-(4-thiazolyl)benziinida2ole derivatives 56 (554, 593). 

Complex Coacervation. This process occurs ia aqueous media and is used primarily to encapsulate water-iminiscible Hquids or water-iasoluble soHds (7). In the complex coacervation of gelatin with gum arabic (Eig. 2), a water-iasoluble core material is dispersed to a desired drop size ia a warm gelatin solution. After gum arabic and water are added to this emulsion, pH of the aqueous phase is typically adjusted to pH 4.0—4.5. This causes a Hquid complex coacervate of gelatin, gum arabic, and water to form. When the coacervate adsorbs on the surface of the core material, a Hquid complex coacervate film surrounds the dispersed core material thereby forming embryo microcapsules. The system is cooled, often below 10°C, ia order to gel the Hquid coacervate sheU. Glutaraldehyde is added and allowed to chemically cross-link the capsule sheU. After treatment with glutaraldehyde, the capsules are either coated onto a substrate or dried to a free-flow powder. 

Devrinol, 2-(l-naphthoxy)-Al,A/-diethylpropionamide/7 i25 5 -5 5 -7/ (napropamide) (23), which is prepared from 1-naphthol, is used as a herbicide (61). Another agricultural chemical, 1-naphthoxyacetic 2Lcid[2976-75-2] (24), is prepared by stirring 1-naphthol with monochloroacetic acid and sodium hydroxide in water at 100—110°C for several minutes. After treatment with concentrated HCl about 94% of the product is obtained (62). 

The solvent is 28 CC-olefins recycled from the fractionation section. Effluent from the reactors includes product a-olefins, unreacted ethylene, aluminum alkyls of the same carbon number distribution as the product olefins, and polymer. The effluent is flashed to remove ethylene, filtered to remove polyethylene, and treated to reduce the aluminum alkyls in the stream. In the original plant operation, these aluminum alkyls were not removed, resulting in the formation of paraffins (- 1.4%) when the reactor effluent was treated with caustic to kill the catalyst. In the new plant, however, it is likely that these aluminum alkyls are transalkylated with ethylene by adding a catalyst such as 60 ppm of a nickel compound, eg, nickel octanoate (6). The new plant contains a caustic wash section and the product olefins still contain some paraffins ( 0.5%). After treatment with caustic, cmde olefins are sent to a water wash to remove sodium and aluminum salts. 

Wastewater Treatment Plants. Numerous studies have shown that phthalates in wastewater systems are removed to a significant extent by treatment plants. The concentration of phthalates in both domestic and industrial wastewater was measured before and after treatment (55). The total level of phthalates in domestic effluent was reduced by treatment from 32.7 to 0.92 )-lg/L and in industrial effluent from 93.6 to 1.06 )-lg/L. Thus between 97 and 99% of the phthalates are removed from wastewater by treatment plants. 

These data together with those from wastewater treatment plants at Darmstadt, Germany Gothenburg and Stockholm, Sweden and Noord-Brabant, the Netherlands, show that the concentrations of DEHP, and in some cases total phthalates, entering wastewater treatment plants vary from 1 to 167 )-lg/L. After treatment the concentrations range from <1 to 36.8 )-lg/L. 

Sodium aluminate is used in water purification, in the paper industry, for the after treatment of Ti02 pigment, and in the manufacture of aluminum containing catalysts and zeoHte. Worldwide markets are in the range of 125,000 t/yr (19). 

The most common thickener is the circular basin type shown in Figure 7. After treatment with flocculant, the feed stream enters the central feed well which dissipates the stream s kinetic energy and disperses it gendy into the thickener. The feed finds its height in the basin where its density matches the density of the inside suspension and spreads out at that level. SoHds concentration increases downward in an operating thickener giving stabiHty to the process. 

A number of after-treatments with polyester copolymers carried out after sodium hydroxide processing are reported to produce a more hydrophilic polyester fabric (197). Likewise, the addition of a modified cellulose ether has improved water absorbency (198). Other treatments used on cotton and blends are also effective on 100% polyester fabrics (166—169). In this case, polymeri2ation is used between an agent such as DMDHEU and a polyol to produce a hydrophilic network in the synthetic matrix (166—169). 

Inorganic heavy metals are usually removed from aqueous waste streams by chemical precipitation in various forms (carbonates, hydroxides, sulfide) at different pH values. The solubiUty curves for various metal hydroxides, when they are present alone, are shown in Figure 7. The presence of other metals and complexing agents (ammonia, citric acid, EDTA, etc) strongly affects these solubiUty curves and requires careful evaluation to determine the residual concentration values after treatment (see Table 9) (38,39). 

Fabric Construction for Water RepeUency. Fabric constmction, including twist, ply, and coarseness of yams, affects the performance of water repeUents. Waterproof films can more easUy be formed on close weaves than on open-weave fabrics. Hydrophobic finishes, which make individual fibers repeUent without altering fabric porosity, are generaUy appUed to fabrics whose pores are smaU (37). The relation of rainwear fabric constmction to the performance of repeUents has been reviewed (38). Some reports indicate that fabric roughness reduces repeUency (28,37). Mechanical action on fabrics, even after treatment, can reduce repeUency if the action increases fiber roughness or exposes fibers that have Utfle repeUent treatment. 

This is apparentiy the reason for the high washfastness of these complexes as compared to their unmetallized precursors (48). The dichromate-acid after-treatment that is used technically oxidizes primarily cystine configurations ia the wool, which converts Cr(VI) to Cr(III). Alternatively, the fiber may be pretreated with dichromate whereby essentially the same final shade is obtained, although it is not known whether the same complexes are formed. 

In all antiseptic testing, it is recognized that skin and mucous membranes to which products ate appHed cannot be disinfected or sterilized but it is possible to significantly reduce the population of transient and resident pathogenic bacterial flora. AH in vivo test methods requite a deterrnination of the bacteria on the skin before and after treatment. Because of the normal variation in bacterial population of the skin of different people, a number of people must be tested in order to make a statistical analysis of the results. Different parts of the body are used for different tests. In aH of the tests the details of the protocol ate extremely important and must be strictly adhered to in order to obtain reproducible results. 

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