Hydrocarbon particle size

Poorly sorted sediments comprise very different particle sizes, resulting in a dense rock fabric wifh low porosify. As a resulf the connate water saturation is high, leaving little space for the storage of hydrocarbons. Conversely, a very well sorted sediment will have a large volume of space between the evenly sized components, a lower connate water saturation and hence a larger capacity to store hydrocarbons. Connate water is the water which remains in the pore space after the entry of hydrocarbons. 

Carbide lime is a waste lime hydrate by-product from the generation of acetylene from calcium carbide and may occur as a wet sludge or dry powder of widely varying purity and particle size. It is gray and has the pungent odor associated with acetylene (see Hydrocarbons, acetylene). 

Dispersions. In phenoHc resin dispersions, the continuous phase is water or a nonpolar hydrocarbon solvent. The resin exists as droplets that have particle sizes of 1—20 p.m and are dispersed in the continuous phase. Aqueous dispersions are prepared either in situ during the preparation of the resin itself or by high shear mixing (25,35). 

Liquid toners are suspensions of toner particles in a fluid carrier. The carrier is typically a hydrocarbon. Dielectric, chemical, and mechanical properties of the Hquid must be compatible with the photoreceptor, the suspended toner particles, and the materials of the development equipment. Liquid toners are capable of producing higher resolution than dry toners because of the smaller (3—5 -lm) particle size achievable. Development of the latent image occurs as it passes through a bath of toner and the charged particles are attracted to the oppositely charged surface. 

It was shown in laboratory studies that methanation activity increases with increasing nickel content of the catalyst but decreases with increasing catalyst particle size. Increasing the steam-to-gas ratio of the feed gas results in increased carbon monoxide shift conversion but does not affect the rate of methanation. Trace impurities in the process gas such as H2S and HCl poison the catalyst. The poisoning mechanism differs because the sulfur remains on the catalyst while the chloride does not. Hydrocarbons at low concentrations do not affect methanation activity significantly, and they reform into methane at higher levels, hydrocarbons inhibit methanation and can result in carbon deposition. A pore diffusion kinetic system was adopted which correlates the laboratory data and defines the rate of reaction. 

Manufacture of highly water-absorbent polymers with uniform particle size and good flowability can be carried out by reverse phase suspension polymerization of (meth)acrylic acid monomers in a hydrocarbon solvent containing crosslinker and radical initiator. Phosphoric acid monoester or diester of alka-nole or ethoxylated alkanole is used as surfactant. A polymer with water-absorbent capacity of 78 g/g polymer can be obtained [240]. 

Small-particle-size cement has found a number of uses in production and injection well casing repair jobs [440]. Oil-based cement is particularly useful for water shutoff jobs, because the hydrocarbon slurry sets only in the presence of water, so the oil-producing sections of a reservoir remain relatively damage free after water shutoff. The selective water shutoff with oil-based cement also has been used with polymers crosslinked by metal crosslinkers [442,1178]. 

Acrylics, A copolymer of 2-ethylhexylacrylate and acrylic acid is not soluble either in water or in hydrocarbons. The ester units are hydrophobic and the acid units are hydrophilic. An aqueous suspension with a particle size smaller than 10 p can be useful in preparing aqueous hydraulic fracturing fluids [776]. 

J. Dahl, K. Harris, and K. McKown. Uses of small particle size cement in water and hydrocarbon based slurries. In Proceedings Volume, pages 25-29.9th Kansas Univ et al Tertiary Oil Recovery Conf (Wichita, KS, 3/6-3Z7), 1991. 

Diverting agents assist in distributing acid more uniformly through the perforated formation interval (141). These are usually oil-soluble hydrocarbon resin particles. They may be dissolved by post-acid injection of xylene or similar solvents. Oil-soluble waxes, naphthalene, and solid organic acids such as benzoic acid have also been used (142). Best results are obtained using a broad range of particle sizes. 

McDonald, M.A., Storm, D.A., and Boudart, M. 1986. Hydrocarbon synthesis from carbon monoxide-hydrogen on supported iron Effect of particle size and interstitials. J. Catal. 102 386 -00. 

Further support comes from the alcohol co-feeding experiments of Emmett and coworkers, who have shown that co-fed alcohol is hydrogenated to a considerable extent to hydrocarbons. Claeys and Schulz27 have shown that the yield of alcohols strongly decreases with increasing particle size of the catalyst due to the increased residence time of products favoring consecutive dehydration. 

After the catalytic runs no modification of mean particle size is observed for this last system. Conversly, Ru CO) deposited on silica-alumina is readily decomposed at 200°C to metallic particles of 1 nm mean size which are also catalysts for the F-T synthesis. The catalytic activity at 200°C is C i one tenth of the Y zeolite supported ones and methane is practically the only hydrocarbon formed. Electron microscopy examination of the catalyst after reaction reveals a drastic sintering of the... 

Figure 5. The influence of the Ru particles size on the hydrocarbon selectivities Curve 1, distribution for a mean-particle size of 1.5 nm Curve 2, distribution for a mean-particle size of 10 nm initial pressure, 20 bar HJCO = 4/1 reaction temperature,200°C...

Fischer-Tropsch synthesis could be "tailored by the use of iron, cobalt and ruthenium carbonyl complexes deposited on faujasite Y-type zeolite as starting materials for the preparation of catalysts. Short chain hydrocarbons, i.e. in the C-j-Cq range are obtained. It appears that the formation and the stabilization of small metallic aggregates into the zeolite supercage are the prerequisite to induce a chain length limitation in the hydrocondensation of carbon monoxide. However, the control of this selectivity through either a definite particle size of the metal or a shape selectivity of the zeolite is still a matter of speculation. Further work is needed to solve this dilemna. 

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