Slurry Stability Ratio

Very stable operation was maintained for run MG-4 without magnesium sulfate addition with the total Mg2+ concentration stabilizing at about 356 ppm. The sulfate-to-sulfite ratio decreased to 2.0, the filter cake insoluble solids reached 53%, and the slurry settling rate was 2.2 cm/min. The results confirmed the base case solids quality and scrubber performance obtained from run MG-1. 

Petcoke water slurries were prepared at mass ratios ranging from 30 70 to 70 30. EnerSol determined that mixtures of up to 50 50 were pumpable and fed without problems to the RRT reactor. Mixtures with higher petcoke concentrations were difficult to maintain in suspension. Experimentation with surfactants and stabilizers resulted in a pumpable mixture at 65% petcoke and 35% water. 

Stabilizers, dispersants, and particle size distributions can have tremendous impacts on the elongational rheology of coal-water fuels while minimally impacting the shear rheology. In particular, stabilizer structure and aspect ratios of the particles present in the slurry may exert profound influences on the atomization of... 

Ethylene homopolymerization using Phillips catalyst PC600 calcined at 600°C followed by activation with DEAE cocatalyst during the slurry polymerization process was carried out with Al/Cr molar ratios of 7.5, 15.0, and 22.5 [84]. As shown in Fig. 14, a typical single-type polymerization kinetics corresponding to type b in Fig. 10b was observed, which was completely different from the kinetics with the same catalyst activated by TEA at the same conditions (as shown in Fig. 13). This t3 pe of polymerization kinetics could be ascribed to one type of active site (Site-B) formed in two ways. One was similar with the PC600 activated by TEA some chromate Cr(VI) species were reduced to Cr(II) species by ethylene monomer and coordinated with formaldehyde, then formaldehyde-coordinated Cr(ll) sites were transformed to DEAE-coordinated Cr(II) sites by substitution, as shown in Scheme 8. On the other hand, some chromate Cr(VI) species were reduced by DEAE, and then the Al-alkoxy product coordinated with the Cr(Il) sites. Site-B had relatively low activity and high stability. Based on the microstructure analysis, the relative amount of SCBs of polymers obtained from the DEAE systems was even more than that from TEA catalyst systems. This can be explained as follows. Firstly, the reduction ability of DEAE was weaker than that of TEA. More Cr(VI) species... 

Suzuki and Suga reported the use of clays as solid acids to support and activate metallocene catalysts for olefin polymerization. They were able to use much less alkylaluminmn cocatalyst relative to solution polymerization conditions. The clays were slurried with AlMeg in toluene, then treated with a solution containing zirconocene dichloride, II, and AIMeg. The metallocenium cation was presumed formed via abstraction of chloride and/or methyl ligands by acidic sites on the surface of the clay, and the low basicity of the clay smface was proposed to stabilize the coordinatively unsaturated cation. Propylene was copolymerized with 250 psi ethylene at 70°C. For acid-treated KIO montmorillonite, an activity of 3300 X 10 kg polymer/(g Zr h) was obtained. Catalysts based on vermiculite, kaolin, and synthetic hectorite all showed lower but still appreciable activities. In this brief report, the Al/Zr ratio was not specified, and the clay dispersion was not reported. 

In a typical commercial process for the manufacture of butyl rubber, isobutene and a small amount of isoprene (l-5-4-5%) are diluted with methyl chloride in a volume/volume ratio monomer/diluent of 30/70. This feed together with a dilute (0-2%) solution of aluminium chloride in methyl chloride are added simultaneously at the base of the reaction vessel which is cooled with liquid ethylene to about -100°C and which contains a powerful stirrer. A violent exothermic reaction occurs and the rubber is formed almost instantaneously. The process operates continuously and the resulting mixture of rubber, solvent and unreacted monomers are fed to a flash tank containing steam or hot water. The solvent and monomer volatilize whilst the rubber forms a slurry in the water. This slurry is treated with a stabilizer and the rubber is then Altered, dried, compacted in an extruder, sheeted on a mill, banded and cut to a size suitable for packing. 

Uses Wetting agent, dispersant for pigments and fillers, stabilizer for emulsion paints, interior and exterior architectural coatings, highly cone, pigment slurries Features Compat. with commercially avail, polymer emulsions Properties YIsh. cl. low-vise, liq. misc. with water in any ratio vise. 20-200 mPa-s ... 

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