Particulate carbon and other components of soot and carbon black

Soot is an unwanted by-product of combustion or pyrolysis of organic compounds. At least four morphologically distinct forms of particulate carbon can be recognized in various types of soot:

1. (1) aciniform carbon (AC), composed of spheroidal carbon particles fused together in aggregates of colloidal dimensions

2. (2) carbonaceous microgel (CM), in which spheroidal carbon particles are embedded in carbon or carbonaceous material

3. (3) carbon cenospheres

4. (4) coke and char fragments.

We have examined 18 soots from various sources. Domestic chimney soots have very little AC but consist mainly of char fragments, CM, ash, and soluble organic fraction (SOF); whereas diesel soots consist mainly of AC and SOF. Carbon black is a manufactured product consisting almost entirely of AC. Carbon blacks can be distinguished from many soots by their morphology, and from all soots investigated in the present study by their purity. Thus, carbon blacks have less than 0.3% SOF removable by toluene, and less than 1% ash, whereas soots exceed at least one of these limits by several fold. Because of differences in origin, function, and composition, common nomenclature carbon black with soot is inappropriate.

BOOK REVIEWS

ANALYSIS AND TESTING OF ADHESIVE BONDS, by G. P. Anderson, S. J. Bennett and K. L. deVries. Academic Press, New York, 1977. 255 pp. ($21 .OO)

ADHESION AND THE FORMULATION OF ADHESIVES by W. C. Wake. Applied Science Publishers, London 1976.

ADHESION OF MELTS AND JOINING OF MATERIALS [Russian]. Yu. V. Naidich, ed. Naukova Dumka, Kiev, 1976. 96 pp. Rub. 0.86.     

Modification and re-interpretation of Geldart's classification of powders

In developing his powder classification, Geldart [D. Geldart, Powder Technol. 7 (1973) 285.] employed fluidization data obtained only at ambient temperature and pressure and from beds fluidized only with air. Unfortunately, industrial applications of fluidized bed technology invariably are at elevated pressure and temperature and with fluidizing gas other than air. Geldart classification of powders does not apply at elevated pressure and temperature. There are ample evidences reported in the literature indicating that normally Geldart Group B powders at ambient conditions, such as polymer particles, can behave like a Group A powder under polymerization conditions at elevated pressure and moderate temperature with substantial emulsion-phase expansion, relatively small bubbles, smooth fluidization, and reduced gas bypassing [J.R. Grace, Can. J. Chem. Eng. 64 (1986) 353; I.D. Burdett, R.S. Elsinger, P. Cai, K.H. Lee, Gas-phase fluidization technology for production of polyolefins, in Fluidization X, Eds. M. Kwauk, J. Li, W.C. Yang, 2001, pp. 39-52; P.N. Rowe, P.U. Foscolo, A.C. Hoffmann, J.G. Yates, X-ray observation of gas fluidized beds under pressure, in Fluidization IV, Eds. D. Kunii, R. Toei, 1983, pp. 53-60]. Similar findings were also reported for Geldart Group B powders fluidized by supercritical carbon dioxide at elevated pressures [C. Vogt, R. Schreiber, J. Werther, G. Brunner, Fluidization at supercritical fluid conditions, in Fluidization X, Eds. M. Kwauk, J. Li, W.C. Yang, 2001, pp. 117-124; C. Vogt, R. Schreiber, G. Brunner, J. Werther, Powder Technol. 158 (2005) 102; D. Liu, M. Kwauk, H. Li, Chem. Eng. Sci. 51 (1996) 4045; M. Poletto, P. Salatino, L. Massimilla, Chem. Eng. Sci. 48 (1993) 617; A. Marzocchella, P. Salatino, AIChE J. 46 (2000) 901].The original Geldart's classification is modified and re-interpreted in this paper by plotting a dimensionless density against the Archimedes number. The new parameters allow powders with different properties fluidized at different pressures and temperatures with gases of different properties to be plotted in the same graph. The proposed modification successfully transforms the normally Geldart Group B particles at ambient conditions to Group A classification when fluidized at elevated pressure and temperature. The selection of these two parameters, the dimensionless density and the Archimedes number, for plotting is not arbitrary, however. The experimental and theoretical development is discussed.     

Quantitative fatty acid analysis of vegetable oils by gas-liquid chromatography

Summary The fatty acid composition of a number of vegetable oils and of two synthetic mixtures of methyl esters are compared by gas-liquid chromatography and by standard methods. The calculated iodine values from G.L.P.C. results are in good agreement with measured iodine values and are indicative of the reliability of the G.L.P.C. values. Standard methods gave lower values for linoleic acid and higher values for linolenic acid than did G.L.P.C. This deviation was particularly evident in oils with a high proportion of linolenic acid,e.g., linseed oil. The results of G.L.P.C. are considered to be accurate to within one unit percentage. Thermal stability of the polyester polymers can be improved by using 1,4-butanediol or ethylene glycol as the polyols instead of diethylene glycol. Issued as N.R.C. No. 5373. Presented at 32nd annual fall meeting, American Oil Chemists' Society, October 20–22, 1958, Chicago, Ill. National Research Council of Canada Postdoctorate Fellow, 1957     

取食不同寄主植物的小菜蛾对定虫隆敏感性的变化

取食不同寄主植物的小菜蛾３龄幼虫对定虫隆的敏感性发生了显著的变化。其中，以取食萝卜的小菜蛾３龄幼虫最为敏感，其次是甘蓝、菜心、西洋菜和白菜，取食花椰菜的最不敏感。但用不同寄主植物饲养小菜蛾一个完整的世代，再统一用菜心饲养至３龄，用定虫隆生测的结果是，其敏感性差异不明显。本文还对因不同寄主植物诱导的小菜蛾药剂敏感性变化的实质进行了讨论。     

Electrochemical properties of apatite and other minerals of Zambian phosphate ores in aqueous solution

A microelectrophoresis technique was used to study the electrochemical properties of apatite, quartz and hornblende from Chilembwe phosphate ore;and apatite, calcite and magnetite from Kaluwe phosphate ore. The tests were conducted in distilled water and the water near the source of the phosphate ores under study.The apatite from Chilembwe gave an isoelectric point (i.e.p.) value of pH 6 in distilled water while in Mankwala Dam water the i.e.p. was of pH 4. Quartz and hornblende were negatively charged throughout the entire pH range studied in both cases. Apatite from Kaluwe showed an i.e.p. value of pH 3.8 while calcite and magnetite had i.e.p. values of pH 6.1 and 4.1 in distilled water, respectively. However, in Kaluwe water the i.e.p. of calcite shifted to pH 8.8 resulting in a charge reversal on either side of the i.e.p. There was no marked difference in the i.e.p. values of apatite and magnetite in Kaluwe water from those in distilled water. Comparison of zeta potential-curves for different apatites showed that they exhibit different i.e.p. values because of their variable composition.     

More on the optimization of batch composition

The discussion of coke quality and the optimization of batch composition by V.P. Lyalyuk, D.A. Kassim, I.A. Lyakhova, and V.P. Sokolova (Coke Chemistry, 2012, vol. 55, no. 12, pp. 448–452) is appraised. The scientific principles underlying the optimization of batch composition are considered.     

In-situ monitoring of the stabilization with hydrogen of free radicals thermally induced from coal using high pressure e.s.r., d.t.a. and p.d.a. equipment

High temperature, high pressure e.s.r. measurements of the hydrogenation reaction of Taiheiyo coal in the presence of catalysts were carried out to understand the stabilization of thermally and/or catalytically induced free radicals. A decrease in free radical concentration with increasing temperature was observed for ZnCl₂ and SnCl₂ · 2H₂O catalysts at 10MPa under hydrogen gas. High pressure modified single-cell d.t.a. and p.d.a. equipment augmented the uniquely designed high temperature, high pressure e.s.r. cell. The hydrogenation reaction was monitored under the same experimental conditions as for e.s.r. From the results of the combination of high temperature, high pressure e.s.r. with high pressure d.t.a. and p.d.a., it was established that H₂ molecules can react efficiently with free radicals from coal molecules created by the presence of ZnCl₂ and SnCl₂ · 2H₂O catalysts.     

Studies on copolymers of acrylonitrile with resins of furfuryl alcohol: 1. Preparation and thermal properties

Copolymers of acrylonitrile with a furfuryl alcohol resin have been prepared by a free radical reaction, and have been characterized by n.m.r. and i.r. spectroscopy. Their t.g.a. has been performed in air and in a nitrogen atmosphere, to permit the recognition of a number of stages in the weight loss process. D.s.c., also in air and in nitrogen, has identified a number of exothermic and one endothermic process in the copolymers. Solid state cross-polarization/magic angle spinning ¹³C n.m.r. spectroscopy and i.r. spectroscopy has been used to obtain some insight into the chemistry of the various chemical changes, which in air are completed by combustion and in nitrogen leave a carbon.     

分散红73和分散蓝183及其混合物在超临界二氧化碳中溶解度的测定与关联(英文)

The solubility of disperse dyes and their mixture in supercritical carbon dioxide is an important property in study and development of supercritical fluid dyeing technology. In this study, solubilities of C.I. Disperse Red 73, C.I. Disperse Blue 183 and their mixture in supercritical CO2 are measured at temperatures from 343.2 to 383.2 K and pressures from 12 to 28 MPa with a static recirculation method. Under the experimental conditions for the binary (C.I. Disperse Red 73 + CO2 or C.I. Disperse Blue 183 + CO2) and ternary (C.I. Disperse Red 73 + C.I. Disperse Blue 183 + CO2) systems, the solubilities increase with pressure. The solubility of C.I. Disperse Blue 183 decreases with the increase of temperature when the pressure is lower than 16 MPa, and the trend is opposite when the pressure is higher than 16 MPa. However, there is no crossover pressure for C.I. Disperse Red 73. The solubilities are also affected by molecular polarity of dyes. The co-solvent effect exhibited in the dissolving process of mixed dyes promotes their disso-lution in supercritical CO2. The experimental data of solubilities of C.I. Disperse Red 73, C.I. Disperse Blue 183, and their mixture are correlated with the Chrastil model and Mendez-Santiago/Teja model. The former is more accurate.