Granular forms

Solids by solvents. The various forms of Soxhlet apparatus illus trated in Section 11,44 can be purchased with ground glass joints. A simplified form, in which the fragile side tubes are absent, is shown in Fig. II, 58, 1. The material to be extracted, if of granular form, may rest upon a sintered glass disc or upon a removable septum ... 

It is important to use recently-prepared pure sodamide, which must be of fine granular form. Old material of irregular lumpy form, even if ground gives poor results, and should not be employed. The sodamide may be prepared as detailed in Section 11,50,j. A satisfactory grade is marketed by May and Baker Ltd. 

Fig. 2. Fertilizers in the prilled or granular form (a), prilled ammonium nitrate (b), prilled urea (c), granular urea (d), granular diammonium phosphate ...

The salt is packaged ia 45-kg multiwaH bags or fiber dmms of 45, 170, or 181 kg. It is available ia both powdered and granular forms with densities of 1.04 and 1.44 g/cm (65 and 90 lb/fT), respectively. Only the powdered grade is authorized by and registered with the EPA for use ia pesticide formulations, with the further proviso that it must be tinted blue or green, or otherwise discolored. The word poison appears on all labels together with first-aid information. 

Density. Density of LLDPE is measured by flotation in density gradient columns according to ASTM D1505-85. The most often used Hquid system is 2-propanol—water, which provides a density range of 0.79—1.00 g/cm. This technique is simple but requires over 50 hours for a precise measurement. The correlation between density (d) and crystallinity (CR) is given hy Ijd = CRj + (1 — Ci ) / d, where the density of the crystalline phase, ify, is 1.00 g/cm and the density of the amorphous phase, is 0.852—0.862 g/cm. Ultrasonic methods (Tecrad Company) and soHd-state nmr methods (Auburn International, Rheometrics) have been developed for crystallinity and density measurements of LLDPE resins both in pelletized and granular forms. 

ChlorinatedIsocya.nura.tes. The cyanuric acid-based sanitizers, introduced for pool use in 1958, are stable crystalline compounds with moderate-to-high available CI2. Sodium dichloroisocyanurate (Dichlor), sold in granular form, dissolves rapidly, whereas trichloroisocyanuric acid (Trichlor) dissolves very slowly and is widely used in the form of tablets or sticks in feeders, floating devices, or in the pool skimmer. 

Clays composed of attapulgite, montmorillonite, and kaoHnite are used for pesticides in finely pulverized or granular form. Granular formulations are reportedly less expensive, more easily handled, reduce loss caused by wind drift, and produce a more effective coverage. 

Most spray-dried instant coffees have been marketed in a granular form, rather than the small spherical spray-dried form, since the mid-1960s. The granular appearance is achieved by steam fusing the spray-dried material in towers similar to the spray drier. Belt agglomerators are also common. 

Cyanuric acid is sold mainly in coarse granular form, >85% 2—0.15 mm (10 to 100 mesh). It is also available in powdered form. Typical analysis of commercial CA is CA >98.5% ammelide <1% water <0.6% pH of 1% slurry >2.8. Eor the chlorinated derivatives ... 

Heterogeneous reactions of industrial significance occur between all combinations of gas, liquid, and solid phases. The solids may be inert or reac tive or catalysts in granular form. Some noncatalytic examples are listed in Table 7-11, and processes with solid catalysts are listed under Catalysis in Sec. 23. Equipment and operating conditions of heterogeneous processes are covered at some length in Sec. 23 only some highlights will be pointed out here. 

The reacting sohd is in granular form. Decrease in the area of the reaction interface occurs as the reaction proceeds. The mathematical modeling is distinguished from that with flat surfaces, which are most often used in experimentation. 

Activated carbon is available in powdered form (200-400 mesh) and granular form (10-40 mesh). The latter is more expensive but is easier to regenerate and easier to utilize in a countercurrent contactor. Powdered carbon is applied in well-mixed shiny-type contactors for... 

Tn comparing the content of drug extract in the final product, teas in granule form are usually very much inferior to instant teas which arc prepared from spray-dried extracts teas in granular form, in addition to 97 -98% filler and carrier substances often contain only 2-3% dry extract, while in spray-dried products almost ten times as much, viz on average 20%, drug extract is present. 

Fluidized-bed catalytic cracking units (FCCUs) are the most common catalytic cracking units. In the fluidized-bed process, oil and oil vapor preheated to 500 to SOOT is contacted with hot catalyst at about 1,300°F either in the reactor itself or in the feed line (called the riser) to the reactor. The catalyst is in a fine, granular form which, when mixed with the vapor, has many of the properties of a fluid. The fluidized catalyst and the reacted hydrocarbon vapor separate mechanically in the reactor and any oil remaining on the catalyst is removed by steam stripping. 

In suspension polymerization, the monomer gets dispersed in a liquid, such as water. Mechanical agitation keeps the monomer dispersed. Initiators should be soluble in the monomer. Stabilizers, such as talc or polyvinyl alcohol, prevent polymer chains from adhering to each other and keep the monomer dispersed in the liquid medium. The final polymer appears in a granular form. 

The final product is marketed as an anhydrous crystalline or monohydrate crystalline compound available as a powder or in granular form. 

Silicon is the second most abundant element in the Earth s crust. It occurs widely in rocks as silicates, compounds containing the silicate ion, Si032, and as the silica, Si02, of sand (Fig. 14.33). Pure silicon is obtained from quartzite, a granular form of quartz (another solid phase of SiOz), bv reduction with high-purity carbon in an electric arc furnace ... 

Starch is a widely distributed material which occurs in roots, seeds, and fruits of plants. For commercial use, com is the principal source, though wheat and potatoes are also used. Starch is extracted by grinding with water, filtering, centrifuging, and drying, a process which yields starch in a granular form. 

Dust explosion possible if in powder or granular form, mixed with air. If dry, it can be charged electrostatically by swirling, pneumatic transport, pouring, etc. 

Platinum catalysts were prepared by ion-exchange of activated charcoal. A powdered support was used for batch experiments (CECA SOS) and a granular form (Norit Rox 0.8) was employed in the continuous reactor. Oxidised sites on the surface of the support were created by treatment with aqueous sodium hypochlorite (3%) and ion-exchange of the associated protons with Pt(NH3)42+ ions was performed as described previously [13,14]. The palladium catalyst mentioned in section 3.1 was prepared by impregnation, as described in [8]. Bimetallic PtBi/C catalysts were prepared by two methods (1) bismuth was deposited onto a platinum catalyst, previously prepared by the exchange method outlined above, using the surface redox reaction ... 

In this method the PCM is mixed with expanded graphite in a compounding process. The result is a compound in granular form (Figure 123). 

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