Influence of cultural conditions on coal solubilization by Penicillium simplicissimum

Sub-bituminous coal, preoxidized with nitric acid and treated with sodium hydroxide solutions to obtain a water-soluble extract, was used for the study of coal degradation by Penicillium simplicissimum. The influence of different carbon and nitrogen sources was examined in connection with growth and production of acid-precipitable coal polymers. The yield was increased after the addition of maltose, lactose and cellobiose while glucose, fructose and xylose had little effect. An organic nitrogen source, yeast extract, was an improved source of nitrogen compared with ammonium chloride. The coal-degrading system appeared before the depletion of the carbon or nitrogen source. In addition, the effects of initial pH of the culture medium demonstrated an increase in the yield of coal polymers up to a pH of 7.5. Above this pH, non-biological catalysis increased gradually. However Ca²⁺ and Mn²⁺ increased the yield of coal polymers over a 14-day period, but yield was unaffected by Cu²⁺, Al³⁺ and Fe²⁺.     

Changes in the physical structure of coal on partial solubilization

Changes in the physical structure of Alberta hvCb coal upon partial solubilization in tetralin, Athabasca bitumen and the oil fraction from the bitumen were determined from gas adsorption measurements, mercury porosimetry and petrographic examination. It was shown that solubilization of the coal generated new micropores, while the macropore structure was degraded. Resistance to extraction due to pore structure is considered to be probably of minor importance. The experimental results suggest that low molecular weight material in the coal was preferentially liquefied.     

Optimization of lipase production by Penicillium simplicissimum in soybean meal

BACKGROUND: Lipase production by Penicillium simplicissimum using soybean meal as substrate has been investigated. A factorial design technique was used to evaluate the effects of incubation temperature, initial moisture of the meal and substrate supplementation with low cost supplements, on lipase production. Soybean oil and wastewater from a slaughterhouse, which is rich on oil and fat, corn steep liquor and yeast hydrolysate, were tested as supplementary carbon and nitrogen sources. RESULTS Cultivation conditions were optimized for the production of lipase by factorial design and response surface methodology. Results show that the microorganism produces very low protease activity (0.21 U gds^?1 dry substrate), which helps to maximize lipase production. Soybean meal without supplements appears to be the best medium of those tested for lipase production by P. simplicissimum. CONCLUSION: This work showed that temperature and moisture are the factors that most strongly influence lipase production by P. simplicissimum using soybean meal as substrate. The growth conditions that optimize lipase production are 27.5 °C using substrate with 550 g kg^?1 of initial moisture. In optimum conditions lipase activity of 30 U gds^?1 dry substrate was obtained. Copyright © 2007 Society of Chemical Industry     

氟铵助溶法从粉煤灰提取氧化铝新工艺的研究

针对传统的从粉煤灰中提取氧化铝方法存在的问题，采用氟化铵助溶法从粉煤灰中提取氧化铝。从实验原理、工艺路线、工艺参数等方面进行实验研究。研究结果表明，采用氟铵助溶法提取氧化铝，铝的溶出率和Al2O2的含量均可达到97％以上；采用氟铵助溶工艺，反应基本上处于常温常压下工作，避免了高温烧结工艺，节约了能源，降低了成本；生产过程中产生的废气、废液、废渣基本实现了合理利用。     

Surface activity and solubilization of a novel series of functional polyurethane surfactants

Functional polyurethane surfactants (di‐block and tri‐block) were synthesized by addition polymerization of 2,4‐toluenediisocyanate with poly(propylene oxide) and monoallyl‐end‐capped poly(ethylene oxide). The chemical structure of the polyurethane surfactants was confirmed by Fourier transform infrared and ¹H NMR spectroscopy. These polymeric surfactants were found to have excellent surface activity. The lowest surface tension of polyurethane surfactant aqueous solutions could be reduced to 37.6 mN m^?1. All the polyurethane surfactants synthesized had low critical micelle concentrations and could reduce the surface tension even at very low concentration levels (10^?6–10^?5 mol L^?1). The solubilization of toluene in micelles of the synthesized polyurethane surfactants was studied using UV‐visible spectroscopy, and the results showed that they all exhibited good solubilization capacity. Possible solubilization positions of toluene in the micelles are conjectured. Copyright © 2006 Society of Chemical Industry     

Liquefaction and/or solubilization of Spanish coals by newly isolated microorganisms

A screening procedure has been set up for isolating microorganisms capable of liquefying coal. Spanish coals were used in the tests, namely a brown lignite from Galicia, sub-bituminous coal from Teruel and hard coal from Minas Figaredo S.A. (Asturias). Among the isolated strains several microorganisms proved capable of liquefying untreated lignite. When lignites were pretreated a more intense and rapid liquefaction was achieved, chelating agents being among the best pretreatments. None of the isolated microorganisms could satisfactorily liquefy sub-bituminous and hard coals in solid media. On the other hand, some fungi grew specifically on the untreated coals, engulfing them and in many cases a soft slurry was obtained. Several of the isolated microorganisms were able to solubilize all three untreated Spanish coals in liquid media. Coal solubilization was measured spectrophotometrically at 300, 400 and 450 nm.     

Inoculum strategies for Penicillium simplicissimum lipase production by solid‐state fermentation using a residue from the babassu oil industry

Two alternative inoculation strategies for lipase production by the fungus Penicillium simplicissimum were tested in solid‐state fermentation using a residue from the babassu oil industry (babassu cake). Conventional spore inoculation was compared with fungal pellets grown in liquid medium and with inocula consisting of fermented cake. Fungal pellets delayed lipase production whereas fermented cake accelerated enzyme synthesis, yielding a productivity of 0.45 U g^?1 h^?1, which is equivalent to the highest values obtained with conventional inocula. Therefore, a 2² factorial design was used to determine the best conditions for lipase production with fermented cake as inoculum strategy, varying the inoculum propagation time and inoculum concentration. Lipase activity and productivity reached 30 U g^?1 and 0.63 U g^?1 h^?1, respectively, with 10% inoculum and 36 h. Thus, fermented cake inocula increased production 1.5‐fold with 10 times fewer spores than in conventional inoculation, indicating that fermented solids are an interesting alternative for inoculum development in solid‐state fermentation, mainly for large‐scale processes. Copyright © 2007 Society of Chemical Industry     

Characterization of liquid product from the reaction of coal with hydrogen atoms

An oily product formed by the reaction of a domestic subbituminous coal (Taiheiyo coal) with hydrogen atoms at 200 °C, has been characterized. The material is essentially composed of C₅-C₂₂ alkanes and cycloalkanes. The $\text{H}\text{C}$ ratio, specific gravity and refractive index were 1.81, 0.855 and 1.447, respectively. The absence of heteroatoms, alkenes and aromatics in the product is the outstanding feature of the coal liquefaction induced by hydrogen atoms.     

Distribution of inorganic and organic substances in the hydrocyclone separated Slovak sub-bituminous coal

A low-rank Slovak sub-bituminous coal from the Handlová deposit was physically treated by washing in a water-only cyclone with the goal to find the separation effect for inorganic (mainly Fe-bearing minerals) and organic substances (humic acids, diterpanes). A high-quality coal product with the ash content in the dry matter of 9.02% and carbon content of C^d = 68.12% at a mass yield of 29.51% was obtained using the water-only cyclone processing. At first, the physically treated coal samples were detailed characterized by XRD, ⁵⁷Fe Mössbauer spectroscopy, FT-IR and HR-TEM. In addition to non-crystalline organic coal components, inorganic compounds belonging to silicate minerals (kaolinite, muscovite and quartz) as well as to Fe-bearing sulphide minerals (pyrite) were identified in the sub-bituminous coal by XRD. ⁵⁷Fe Mössbauer spectroscopy detected the presence of iron carbonate (siderite), iron-containing clay mineral and two sulphur-containing minerals (pyrite, jarosite) in the untreated coal. On the other hand, only one Fe-bearing mineral, (pyrite) was found in the washed coal. Effect of the physical separation is also demonstrated in FT-IR spectra, where the peak at 1040 cm⁻¹ representing the silicate component in the untreated sample is not detectable in the washed coal sample. Presence of extractive organic substances, i.e. humic acids and tetracyclic diterpane (16α(H)-phyllocladane), in the hydrocyclone products is also evidenced. It was confirmed that the isolated diterpenoic compound is attendant in the washed product with the lowest ash content and it is assimilated with the organic part of coal. Surprisingly, humic acids were found in the highest concentration in the slurry that has the highest content of ash (63.14%).     

Structural characterization of non-reductively ethylated coal by 13C and 1H n.m.r.

A major portion of some coals can be solubilized by non-reductive ethylation. A part of the solubilized portion of a bituminous highly caking coal was studied by ¹H and ¹³C nuclear magnetic resonance techniques. It was demonstrated that important structural information can be obtained by this method for the original insoluble material in coal. It was found that, in the investigated coal, about 40% of the aromatic carbon atoms are protonated and that 6–10% of total carbon atoms existed in original coal as active sites that were amenable to ethylation.     

Reactive intermediate in the alkali-carbonate-catalysed gasification of coal char

Based on results from a variety of experimental measurements, a detailed mechanism is postulated for the action of the inorganic catalyst in char gasification. In this mechanism, a catalyst such as potassium carbonate in contact with char undergoes a chemical and physical transformation to form a molten potassium oxide film that covers the char surface. This film serves as an oxygen transfer medium between the gaseous reactant (H₂O or CO₂) and the char. At the catalyst/char interface, an oxidation-reduction reaction occurs and the anions in the catalyst react with the oxidized char to form a phenolate-type functional group that subsequently splits out CO. The anions are replenished by reaction between the oxidizing gas (H₂O or CO₂) and the oxide at the gas/catalyst interface. Net transport of oxygen from gas to char occurs by diffusion of the species in the molten catalyst film.     

Characterization of fine coal particles by steric field-flow fractionation

Steric field-flow fractionation (steric FFF) is described as a method for the separation and characterization of particulate materials of particle diameter 1 μm. The theoretical basis of steric FFF is described and the concept of apparent particle radius is introduced. Experiments are described using coal ground to a few μm mean diameter. Fractionation is demonstrated by collecting fractions and reinjecting them into the device, after which they re-emerge in a position close to that of the original fraction. A size-distribution curve is obtained and compared to those generated by other means. Possible sources of discrepancies are described. The advantages and potential applications of steric FFF to process control and coal research are discussed.     

树枝状大分子聚酰胺胺对布洛芬的增溶性能研究

采用发散合成法,合成了系列以乙二胺为核的树枝状大分子聚酰胺 胺(PAMAM)和三羟基氨基甲烷改性的聚酰胺 胺,用紫外 可见分光光度计测定了树枝状大分子对布洛芬的增溶能力。结果表明:两类树枝状大分子对布洛芬的增溶量均高于传统的表面活性剂SDS,而且增溶能力均随代数的增加而增加;在引入羟基后,PAMAM增溶能力明显提高,作为一种新型的药物输送剂,显示了良好的应用前景。     

Characterization of the coal fly ash for the purpose of improvement of industrial on-line measurement of unburned carbon content

The influence of selected properties of fly ash on the measurements of an on-line analyser was described. Fly ash studied in the research originated from the pulverized coal fired boiler. The samples were taken using an inspection method within a period of 3 months. Systematic observation of the properties of the ash allowed monitoring of the work of the industrial analyzer during a relatively long period of the power plant work. Samples of coal fly ash were examined for their chemical and physical properties. Morphology was analysed by scanning electron microscopy. Unburned carbon content in fly ash was determined by using loss-on-ignition (LOI) and thermogravimetry analysis (TGA). The particle size distribution of fly ash was examined. Correlation between laboratory and on-line industrial measurements of the unburned carbon content of ash was discussed.     

Characterization of coal—oil mixtures by a pseudo diffusivity parameter

For the use of coal—oil mixtures as combustion fuels stable maintenance of the solid—liquid suspension is vital and for this reason the settling properties of these mixtures were studied with a system of ultrasonic sensors. The sedimentation theory of Smiles, which relies on unsteady state diffusion analogies, was applied successfully to the coal-oil mixtures and pseudo diffusion coefficients were determined.     

Property estimation using structural characterizations: Heat capacities of coal liquids

Three coal liquids were characterized by estimating the concentrations of the functional groups present in the liquids. The concentrations were deduced using data from Chromatographic separations, elemental analysis, ¹H n.m.r., ¹³C n.m.r. and mass spectrometry. The concentration estimates were then used, in conjunction with simple group additivity rules, to estimate the heat capacities of the liquids as a function of temperature. The heat capacity estimates were in excellent agreement with experimentally determined values.     

The application of the f.m.r. technique to coal characterization studies

The mineral magnetite has been detected in a sample of Pittsburgh No. 8 coal by the ferromagnetic resonance technique. The magnetite particles contained in a ground sample were < 0.07 μm diameter and have a chemical composition between Fe_2.98804O₄ and Fe_2.99704O₄. The results of acid treatment indicated that the magnetite is not embedded in the organic coal material, but is readily removed. The use of the f.m.r. technique as exemplified in the present work has important potential in the study of ferro-and ferrimagnetic minerals in raw coal and their interactions with paramagnetic organic free radicals during coal conversion processes.     

Alkyl aryl ethers in lignite solubilization. 1. Study of the process

The chemistry of solubilization of a lignite has been investigated with anisole, 3-methyl anisole and 1,3-dimethoxybenzene catalysed by SbCl₃, ZnCl₂, AlCl₃ and BF₃ as boron trifluoride etherate, at atmospheric pressure and temperatures < 220 °C. 60% of lignite was solubilized in a toluene-ethanol azeotropic mixture. During the process, the solvent is incorporated as an alkylated substratum. The yield increased with activity of the aromatic ether ring and catalyst acidity.     

Characterization of whole coals by 13C CP/MAS spectroscopy at high field

Solid-state 50-MHz ¹³C spectra essentially free of spinning sidebands have been constructed for three bituminous coals by the addition of echo spectra having phase-altered spinning sidebands (PASS). The echo spectra are produced by a modified version of the Dixon pulse sequence. Quantitative analysis of the aromatic carbon content (f_a) from PASS spectra for the three coals compares favourably with results obtained by other methods. Values of f_a are found in the range 0.69–0.73. Removal of the unwanted spinning bands allows absorptions for specific structural units present in the coals to be distinguished and assigned. Spectra show an upfield shoulder at 13–15 ppm, and moderately intense absorptions at 20–24 ppm and ≈30 ppm which are characteristic of several aliphatic structures in different steric environments. In addition to the main aromatic band at ≈120 ppm, absorptions for substituted aromatic carbons appear at ≈140 and ≈155 ppm. Less intense signals from several carbonyl functional groups (160–190 ppm) and oxygen- and nitrogen-substituted aliphatic groups (50–90 ppm) are also present.