Stepwise synthesis of acetic acid from secondary butanol was studied. The oxidation of secondary butanol to methyl ethyl ketone and acetic acid with Co3O4-X and Rh2O3-X binary and ternary catalysts and the oxidation of methyl ethyl ketone to acetic acid with V2O5-X binary catalysts were studied. The reactions were carried out in the presence of water in a temperature range from 170° to 300°C. Over the Co-V(9:1) and Rh-V (8:2) catalysts, secondary butanol formed with high conversion methyl ethyl ketone with selectivity of 80∼93% at 170∼230°C. Other primary and secondary alcohols gave aldehyde or ketone with selectivity of over 90%. Under more severe conditions, secondary butanol formed mainly acetic acid. For example, using the Co-V-Rh (75:25:2) catalyst, secondary butanol yielded 59% and 2% of acetic acid and methyl ethyl ketone, respectively, and it was not dehydrated to n-butenes1). The V2O5-Cr2O3 (6:4) catalyst was found most selective among the V2O5-binary catalysts for oxidation of methyl ethyl ketone to acetic acid whose yield was 78% at 260°C. Under more moderate conditions, the yield of acetic acid was 88% with V2O5-Sb2O5 (4:6) catalyst. As for the one step synthesis of acetic acid from n-butenes, good results were obtained with Co-V-Cr and Co-V-Al catalysts. With Co-V-Al (75:25:20) catalyst, the amount of acetic acid and total acid (acetic acid with other acids such as maleic acid) was obtained with selectivity of 90% at 50% conversion of n-butenes.
The addition reaction of carbon monoxide with ethylene in aqueous hydroiodic acid was investigated under high pressure in the range of 30 to 90kg/cm2. The yield of propionic acid was fairly high and the overall rate equation was: ln[C2H4]0/[C2H4]0-[C2H5COOH]=k1k2HCOPCOt/k-1+k2HCOPCO=Kt Namely, the apparent reaction was a pseudo first order with respect to carbon monoxide and ethylene, and the apparent rate constants mere 3.0×10-5, 13.1×10-5 and 26.8×10-5sec-1 at 100, 120 and 140°C, respectively. From these values, K/PCO's calculated were 0.05×10-5, 0.21×10-5 and 0.43×10-5kg-1•cm2•sec-1 comparable to 0.08×10-5, 0.20×10-5 and 0.30×10-5kg-1•cm2•sec-1 obtained in the reaction of carbon monoxide with ethyl iodide. The overall activation energy has been found to be 16.6kcal/mole, as opposed to that of the latter reaction, i. e., 13kcal/mole. From these results the authors concluded that ethyl iodide was formed as an intermediate product in the reaction of carbon monoxide with ethylene.
Thermal gasification of polyethylene (PE), polypropylene (PP), and polyisobutylene (PIB) was carried out under atmospheric pressure using the flow system of a fixed bed reactor. From an experimental equation, IF=Tθa, product yields were estimated, where IF is the intensity function (°C•seca), T is the reaction temperature (°C), θ is the residence time (sec), and a is a constant (-). The effect of the structure of polyolefin on the value of "a" was also discussed. The pyrolysts conditions used in this study were as follows: temperature, 500∼800°C; the residence time, 0.6∼7.1sec; and the dilution ratio of steam to polymer by weight, 0.6∼7.5. The operating factors were inferred to be reaction temperature and residence time. For a given product yield, these two factors were interchangeable. Equations for yielding methane were expressed as_follows: (PE): IF=Tθ0.04, (PP); IF=Tθ0.05, (PIB); IF=Tθ0.07. As IF was correlated to the product yield, the product yield could be predicted by some appropriate choice of pyrolysis conditions. The value of "a" of a polyolefin was correlated to the activation energy (ΔE) for thermal degradation and to temperature (T1/2) corresponding to 50% weight loss. These two parameters were determined from the TG curve.
The flow activation quantities were experimentally determined at 25.0°C with mineral lubricating oils blended with various concentrations of VI-improver. While polylauryl-methacrylate increases activation volume substantially and decreases activation entropy considerably, it does not affect activation enthalpy. Polyisobutylene changes the quantities only slightly. Molecular interpretation of these observations has been attempted.
Steam reforming of methane, n-pentane and n-heptane over Rh catalysts supported on γ-alumina and silica has been carried out under atmospheric pressure and at 550°C to investigate the influence of the degree of dispersion of Rh on steam reforming and aromatization. The specific catalytic activity expressed by the initial rate of reaction per unit surface area of Rh was found to depend on the degree of dispersion. A good correlation was obtained between the gasification activity and the appearance of surface atoms existing in crystal faces and between the aromatization activity and the appearance of surface atoms existing in low-coordinated positions such as edge or corner atoms. The difference in the active sites on Rh crystal for gasification and aromatization was further confirmed by the study using a pulse technique.
For hydrocarbon synthesis from mixtures of CO and H2, variation in activity and selectivity of Group VIII metals (except osmium)/Al2O3 catalysts with pretreatment temperature in flpwing H2 at 300°C∼800°C, was investigated at 300°C and 1atm using a pulse method and a circulating flow reactor. In addition, variation in the number of surface metal atoms (mS) in those catalysts with varying treatment temperature was also determined using the chemisorption technique. The activities (per unit weight of catalyst; per metal atom in the catalyst) of Pt, Ir, Pd, and Rh catalysts were maximum when they were treated at 500°C, though their mS values monotonously decreased with increasing treatment temperature due to metal sintering. The activity and the mS value of Ru(A) catalyst decreased slightly with increasing treatment temperature. On the other hand, the initial activity and the mS value of Ru(B) increased with increasing treatment temperature, but the steady-state activity decreased. The activities and mS values of Ni and Co increased with increasing treatment temperature. Fe neither adsorbed hydrogen nor showed any activity. The sequence of specific activity (per surface metal atom) was determined as follows: Ru(B), Ru(A)>Ni>Co>Rh>Pd, Pt>Ir The main reaction product was methane, but the hydrocarbon distribution of products varied over a wide range depending more on metal than on treatment temperature. The average molecular weight of product hydrocarbons changed in the following sequence: Ru(B)>Ir>Rh>Ru(A), Ni, Co>Pt>Pd.
Sulfonation of asphalt in the presence of a solvent (1, 1, 2-trichloroethane) was studied to prepare an ion exchanger. When asphalt was sulfonated in the presence of a solvent, the yield of the reaction product was higher than in the reaction in its absence, and the effect increased with increasing amount of solvent. The amount of sulfonation reagent such as sulfuric acid, oleum or sulfur trioxide required to obtain the optimum yield was diminished by presence of a solvent. When asphalt dissolved in solvent was sulfonated with sulfuric acid or oleum, a granular product was formed. Some promising results as ion exchanger were obtained from the measurements of the total ion exchange capacity of the sulfonated asphalt.
Using a binary mixture of isoprene and 2-methyl-2-butene as a feed charge, the effects on extractive distillation with propylene carbonate of various operating parameters such as feed and solvent temperatures, location of entry of the hydrocarbon feed and reflux ratio were studied. Propylene carbonate was tested for its efficient use as an extractive distillation solvent for the separation of dienes from a C5 fraction. As a result, a diene fraction containing no paraffins and only a trace of olefins was obtained. The addition of ethyl carbitol to increase the miscibility of propylene carbonate with hydrocarbons could improve the recovery of the dienes.
A modified θ method of multi-component extractive distillation was proposed. It utilizes the selectivities calculated from the gas-chromatogram obtained with a capillary column. From the comparison of the calculated results with the experimental ones, the method seems to be convenient in predicting approximate values of vapor compositions throughout the tower.
Gas phase adsorption properties of activated carbon prepared from sulfonated asphalt were investigated by comparing with those of commercial activated carbon. As adsorbates sulfur dioxide, nitrous oxide, carbon dioxide, ammonia, ethylene, benzene, methanol, pyridine, acetic acid, carbon tetrachloride and water were used. It was found that gas phase adsorption capacity of activated carbon prepared from sulfonated asphalt was not less superior to that of commercial activated carbon, and as deoderizing agent and as adsorbent for hydrocarbon vapors liberated from automobiles, it could be used effectively. From the gas phase adsorption experiments carried out with the activated carbon prepared from sulfonated asphalt, the following trends were observed: 1) Adsorption capacity for gaseous substances was small at room temperature and it varied with the pressure. 2) Adsorption capacity for vapors of liquid substances was large at room temperature and its pressure dependence was small.
Liquid phase adsorption properties of activated carbon prepared from sulfonated asphalt were investigated by comparing with those of commercial activated carbon. As adsorbates iodine, acetic acid, phenol, methylene blue, sodium dodecylbenzene sulfonate (DBS), rhodamine B, congo red, methyl mercury chloride, lead nitrate and sodium cyanate were used. Adsorption capacity for comparatively small molecular adsorbates such as iodine and acetic acid was almost independent of the yield from raw asphalt and it was the same order of magnitude of commercial activated carbon. On the other hand, adsorption capacity for comparatively large molecular adsorbates such as methylene blue, DBS and congo red increased with decreasing yield. Activated carbon, yield was kept less than 30%, was found to have large adsorption capacity comparable to that of commercial activated carbon for such large molecular adsorbates. The adsorption rate and intraparticle diffusion coefficient for activated carbon from sulfonated asphalt were found to be larger than those for commercial ones.
A propane and butane-utilizing bacterial strain, capable of growth at a comparatively high temperature with a specific growth rate of 0.12hr-1, has been isolated from soil samples by enrichment culture. The optimum temperature and pH range for the growth of the isolate, designated SB-1701, were 35∼40°C and 5.7∼6.7, respectively. Cultivation was carried out with a mixed gas of 20% n-butane and 80% air, using only inorganic salts as the medium. The optimum medium composition which contained trace metallic salts was determined to obtain high productivity. Continuous culture was maintained at a steady state for more than 400 hours in a 20-liter jar fermenter during which the productivity was 1.4g cell/l•hr. The yield based on propane was 0.95g cell/g propane and the yield based on oxygen was 0.41g cell/g oxygen. All experiments were carried out aseptically. SB-1701 has been identified as a new strain of the genus Flavobaclerium. The crude protein content and the amino acid profile of SB-1701 were determined.
This check list has been compiled based on an extensive survey of literature on energy conservation. Major items of energy conservation have been classified into sub-lists in each of the planning, design, and operation phases of petroleum refineries. The check list will be useful for initiating energy conservation programs.