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1.
Waste high-density polyethylene was converted into different hydrocarbon fractions by thermal and thermo-catalytic batch cracking. For the catalytic degradation of waste plastics three different catalysts (equilibrium FCC, HZSM-5 and clinoptilolite) were used. Catalysts differ basically in their costs and activity due to the differences of micro- and macroporous surface areas and furthermore the Si/Al ratio and acidities are also different. Mild pyrolysis was used at 430 °C and the reaction time was 45 min in each case. The composition of products was defined by gas chromatography, Fourier transform infrared spectroscopy, size exclusion chromatography, energy-dispersive X-ray fluorescence spectroscopy and other standardized methods. The effects of catalysts on the properties of degradation products were investigated. Both FCC and clinoptilolite catalysts had considerably catalytic activity to produce light hydrocarbon liquids, while HZSM-5 catalyst produced the highest amount of gaseous products. In case of liquids, carbon numbers were distributed within the C5–C23 range depending on the cracking parameters. Decomposition of the carbon chain could be followed by GC and both by FTIR and SEC techniques in case of volatile fractions and residues. Catalysts increased yields of valuable volatile fractions and moreover catalysts caused both carbon chain isomerization and switching of the position of double bonds.  相似文献   

2.
Degradation of diesel oil in soil using a food waste composting process   总被引:1,自引:0,他引:1  
Joo HS  Shoda M  Phae CG 《Biodegradation》2007,18(5):597-605
We investigated the simultaneous degradation of diesel oil in soil and the organic matter in food waste by composting in 8 l reactors. Using a 0.5 l/min air flow rate, and 0.5-1% diesel oil concentrations together with 20% food waste, high composting temperatures (above 60°C) were attained due to the efficient degradation of the food waste. Petroleum hydrocarbons were degraded by 80% after only 15 days composting in the presence of food waste. In a 28 l reactor scale-up experiment using 1% oil, 20% food waste and 79% soil, removal efficiencies of petroleum hydrocarbons and food waste after 15 days were 79% and 77%, respectively.  相似文献   

3.
Prototheca zopfii is an achlorophyllous alga which degrades oil. It has been found to degrade 10 and 40% of a motor oil and crude oil, respectively, when tested under appropriate conditions. Degradation of the crude oil observed in this study compares well with the amount of degradation accomplished by bacteria. P. zopfii was found to degrade a greater percentage of the aromatic hydrocarbons in motor oil than of the saturated hydrocarbons and a greater percentage of saturated hydrocarbons in crude oil than of aromatic hydrocarbons. Resins and asphaltens were produced during degradation of motor oil, whereas these fractions in crude oil were degraded. P. zopfii did not demonstrate preferential utilization of lower homologues of cycloalkanes and aromatics as has been observed with bacteria.  相似文献   

4.
ZSM-5(38)/Al-MCM-41复合分子筛对纤维素催化热解的影响   总被引:2,自引:1,他引:1  
以纤维素为原料,以自制的不同硅铝比ZSM-5(38)/Al-MCM-41微-介孔复合分子筛为催化剂,在固定床反应器上进行了催化热解实验。采用XRD表征分子筛,采用GC-MS分析生物油成分,考查了催化剂的改变对生物质热解产物及生物油成分的影响。实验结果表明:添加催化剂后,生物油产率降低,且其含水率也有所增加。与未添加催化剂相比,生物油中D L-2,3-丁二醇有明显提高。其中,ZSM-5(38)/Al-MCM-41(20) 最有利于苯酚、愈创木酚 (2-甲氧基-苯酚) 的生成。此外,这几种催化剂均有利于小分子化合物的生成,其中,ZSM-5(38) 有利于C4~C5化合物的生成,微-介孔复合分子筛则有利于C6~C8化合物的生成。  相似文献   

5.
The effect of chemical pretreatments using NaOH, H2O2, and Ca(OH)2 on Empty Palm Fruit Bunches (EPFB) to degrade EPFB lignin before pyrolyis was investigated. Spectrophotometer analysis proved consecutive addition of NaOH and H2O2 decomposed almost 100% of EPFB lignin compared to 44% for the Ca(OH)2, H2O2 system while NaOH and Ca(OH)2 used exclusively could not alter lignin much. Next, the pretreated EPFB was catalytically pyrolyzed. Experimental results indicated the phenolic yields over Al-MCM-41 and HZSM-5 catalysts were 90 wt% and 80 wt%, respectively compared to 67 wt% yield for the untreated sample under the same set of conditions. Meanwhile, the experiments with HY zeolite yielded 70 wt% phenols.  相似文献   

6.
以纤维素为原料,以自制的不同硅铝比ZSM-5(38)/Al-MCM-41微-介孔复合分子筛为催化剂,在固定床反应器上进行了催化热解实验。采用XRD表征分子筛,采用GC-MS分析生物油成分,考查了催化剂的改变对生物质热解产物及生物油成分的影响。实验结果表明:添加催化剂后,生物油产率降低,且其含水率也有所增加。与未添加催化剂相比,生物油中D L-2,3-丁二醇有明显提高。其中,ZSM-5(38)/Al-MCM-41(20)最有利于苯酚、愈创木酚(2-甲氧基-苯酚)的生成。此外,这几种催化剂均有利于小分子化合物的生成,其中,ZSM-5(38)有利于C4~C5化合物的生成,微-介孔复合分子筛则有利于C6~C8化合物的生成。  相似文献   

7.
The influence of the amount of alumina binders on the catalytic performance of Ni/HZSM-5 for hydrodeoxygenation of cyclohexanone was investigated in a fixed-bed reactor. N2 sorption, X-ray diffraction, H2-chemisorption and temperature-programmed desorption of ammonia were used to characterize the catalysts. It can be observed that the Ni/HZSM-5 catalyst bound with 30 wt.% alumina binder exhibited the best catalytic performance. The high catalytic performance may be due to relatively good Ni metal dispersion, moderate mesoporosity, and proper acidity of the catalyst.  相似文献   

8.
Zhang H  Xiao R  Huang H  Xiao G 《Bioresource technology》2009,100(3):1428-1434
Fast pyrolysis of corncob with and without catalyst was investigated in a fluidized bed to determine the effects of pyrolysis parameters (temperature, gas flow rate, static bed height and particle size) and a HZSM-5 zeolite catalyst on the product yields and the qualities of the liquid products. The result showed that the optimal conditions for liquid yield (56.8%) were a pyrolysis temperature of 550 degrees C, gas flow rate of 3.4 L/min, static bed height of 10 cm and particle size of 1.0-2.0mm. The presence of the catalyst increased the yields of non-condensable gas, water and coke, while decreased the liquid and char yields. The elemental analysis showed that more than 25% decrease in oxygen content of the collected liquid in the second condenser with HZSM-5 was observed compared with that without catalyst. The H/C, O/C molar ratios and the higher heating value of the oil fraction in the collected liquid with the catalyst were 1.511, 0.149 and 34.6 MJ/kg, respectively. It was indicated that the collected liquid in the second condenser had high qualities and might be used as transport oil.  相似文献   

9.
The risk of exhaustion of natural resources and raw materials have given rise to emerging trends such as recycling of food waste. From the economical and ecological points of view, conversion of biowaste to high added value compounds has been getting great attention among the science and commercial entities. Due to their high-added value phytochemicals, agricultural and food residues have been a great significant to the researchers around the world. This study focuses on the valorisation of cake derived from sesame oil processing. If the very valuable non-nutrient phytochemicals in sesame cake are not evaluated properly, they would be consumed as just animal feed or fertilizers. They might be employed as antiaging (in pharmaceutical products), or free radical scavenger (in dietary supplements), or preservative additive against lipid oxidation (in fat containing food products). This review article aims to present pharmacological and therapeutic effects of sesame cake extract by pointing out its application in pharmaceutical, cosmetic and food industries.  相似文献   

10.
Poplar leaves, poplar bark and poplar wood were deoxy-liquefied directly in an air-proof stainless steel reactor at different temperatures. The oils from leaves at 350 °C, from bark at 400 °C and from wood at 450 °C, at which the liquid product yields were the maximum, were analyzed by GC–MS. The oils obtained from three parts of poplar tree were quite different from each other in the relative contents of their compositions. The oil from leaves was rich in hydrocarbons (alkanes: C7–C29; aromatics) and poor in phenolics, while oil from wood was rich in phenolics and poor in hydrocarbons. The oil from bark was moderate. Relative contents of hydrocarbons in the leaves oil were as high as 60.01% but decreased to 29.71% in bark oil and 11.43% in wood oil. GC analysis of gases and FT-IR, GC–MS and elemental analysis of oils were performed in this study.  相似文献   

11.
The United States is a major producer of many different types of oilseeds, but the predominant one is soybean, that remarkable legume whose meal and oil serve many animal feed, human food, and domestic industrial product needs. More than half of the soybeans and the products produced from them are exported. The 16 mill MT of soy meal processed and fed in the United States in 1981 constituted 88% of the total oilseed meal, 71% of the high-protein feeds, and 48% of total processed feeds. Of the total soy protein available, less than 5% goes into human food products such as meat extenders, simulated meats, baked goods, dairy product analogs, dietary foods, infant foods, and fermented food products. Less than 1% of soy protein in the United States is used in industrial products, mainly as a binder for pigmented paper coatings. Of the total soy oil available, about 95% is consumed in food products such as margarines, salad oils, and cooking oils. About 5% of soy oil is applied to nonfood uses such as alkyd paints, plasticizer/stabilizers for vinyl plastics, soaps, eraser factices, and many other lesser uses. Other major oilseeds produced in the United States include cottonseed, flaxseed, peanut, safflower, and sunflower. Corn oil is produced in significant quantities as a by-product of the corn starch industry. The oilseed crops having the greatest oil productivity are peanut and sunflower. However, sunflower meal has certain deficiencies for feed and food uses. If the United States is to draw upon oilseed crops as significant contributors to feed, food, industrial products, and agricultural fuel needs, greatly improved productivity will be needed either from new oilseed crops or from improved varieties of present commercial crops.  相似文献   

12.
A cell-free system which catalyzes the biosynthesis of terpene hydrocarbons when supplemented with mevalonate, Mn2+, and ATP was prepared from the scutellum-embryonic axis region of maize seedlings. The capacity of this system for the production of terpene hydrocarbons was enhanced 50- to 100-fold when the seedlings were exposed for 48 hours to the fungus Rhizopus stolonifer prior to tissue homogenization. The fungi Aspergillus niger, Fusarium moniliforme, and Verticillium albo-atrum also elicited this biosynthetic enhancement. The terpene hydrocarbon products were separable into six fractions by argentation thin layer chromatography. Radioactivity was contributed to five of these fractions when either geranylgeranyl pyrophosphate or copalyl pyrophosphate was supplied as substrate, suggesting that polycyclic diterpenoid hydrocarbons were the main products. Large scale biosynthetic reactions led to the acquisition of about 1 milligram of terpene hydrocarbon products plus some more polar terpenoid products. Analysis of the hydrocarbon products by gas chromatography and mass spectrometry led to the separation of six distinct diterpene hydrocarbons plus a fraction with a molecular weight of about 550. Three of the diterpene hydrocarbons were identified as kaur-16-ene, kaur-15-ene (isokaurene), and pimara-8(14),15-diene. None of the terpene hydrocarbon fractions tested displayed antifungal activity in the Cladosporium cucumerinum thin layer plate assay.  相似文献   

13.
The aim of this work was to evaluate the effect of keratinous waste addition on oil-hydrocarbon removal, through a mixed culture of oil-degrading bacteria, with the ability to secrete keratinases. The mixed culture was grown in the media with oil, or oil supplemented with chicken-feathers as the keratinous waste. Residual oil-hydrocarbons were determined as total petroleum hydrocarbons (TPHs) and oil fractions and then quantified by GC–FID and GC–MS.Results showed that in presence of the keratinous waste, the removal of oil-hydrocarbons was 57,400 mg l?1, meanwhile the treatment without waste presented an oil-hydrocarbons removal of 35,600 mg l?1. The aliphatic fraction was the most removed in both treatments. In addition, chromatographic profiles indicated that the aliphatic fraction showed different degradation pattern; in the presence of keratinous wastes, the C18 to C28 compounds were preferably removed over the C10 to C17. The addition of keratinous waste not only improved the oil-hydrocarbons removal but, it changed the removal pattern of the target hydrocarbons.  相似文献   

14.
Hydrothermal processing of high lipid feedstock such as microalgae is an alternative method of oil extraction which has obvious benefits for high moisture containing biomass. A range of microalgae and lipids extracted from terrestrial oil seed have been processed at 350 °C, at pressures of 150-200 bar in water. Hydrothermal liquefaction is shown to convert the triglycerides to fatty acids and alkanes in the presence of certain heterogeneous catalysts. This investigation has compared the composition of lipids and free fatty acids from solvent extraction to those from hydrothermal processing. The initial decomposition products include free fatty acids and glycerol, and the potential for de-oxygenation using heterogeneous catalysts has been investigated. The results indicate that the bio-crude yields from the liquefaction of microalgae were increased slightly with the use of heterogeneous catalysts but the higher heating value (HHV) and the level of de-oxygenation increased, by up to 10%.  相似文献   

15.
In-situ catalytic upgrading of biomass fast pyrolysis vapors was performed in a fixed bed bench-scale reactor at 500 °C, for catalyst screening purposes. The catalytic materials tested include a commercial equilibrium FCC catalyst (E-cat), various commercial ZSM-5 formulations, magnesium oxide and alumina materials with varying specific surface areas, nickel monoxide, zirconia/titania, tetragonal zirconia, titania and silica alumina. The bio-oil was characterized measuring its water content, the carbon-hydrogen-oxygen (by difference) content and the chemical composition of its organic fraction. Each catalytic material displayed different catalytic effects. High surface area alumina catalysts displayed the highest selectivity towards hydrocarbons, yielding however low organic liquid products. Zirconia/titania exhibited good selectivity towards desired compounds, yielding higher organic liquid product than the alumina catalysts. The ZSM-5 formulation with the highest surface area displayed the most balanced performance having a moderate selectivity towards hydrocarbons, reducing undesirable compounds and producing organic liquid products at acceptable yields.  相似文献   

16.
Rugosa rose (Rosa rugosa Thunb.) is one of the most common rose species in Poland. It has mild soil and climate requirements and is resistant to low temperatures. Rugosa rose hips are a valuable raw material used in food and pharmaceutical industries, while flowers and petals may be a source of fragrant products, such as essential oil and hydrolate. The main aim of this study was to verify usefulness of dried R. rugosa petals for essential oil and hydrolate production. We also assessed the use of rugosa rose petals remaining after oil distillation for hydrolate production.The R. rugosa dried petals immersed in water were subjected to simple distillation and five fractions of primary rose hydrolate were obtained. In parallel, essential oil from the second sample of petals was obtained by hydrodistillation in Clevenger-type apparatus. The distillation residue was used for obtaining four fractions of secondary hydrolate. The volatiles from hydrolate fractions were isolated by liquid–liquid extraction with diethyl ether. The essential oil and hydrolate volatiles were analyzed by GC–FID–MS.Hydrolate fractions contained similar amounts of volatiles (20–30 mg/L) with the exception of the first fraction of primary hydrolate (60 mg/L). β-Phenylethanol, citronellol, geraniol, and nerol were the main volatile constituents of primary hydrolate. β-Phenylethanol, citronellic acid, and geranic acid were the main volatile constituents of secondary hydrolate. The content of alcohols decreased, while the content of monoterpene esters (citronellyl, neryl, and geranyl acetate) as well as monoterpene acids (citronellic, neric, and geranic acid) increased in successive fractions of both hydrolates.The scent and composition of essential oil and hydrolate obtained from R. rugosa petals were similar to those of rose oil and rose water produced from damask rose (Rosa damascena Mill.). This proves, that rugosa rose distillation products may become an alternative to fragrant damask rose products.  相似文献   

17.
Hu Y  Zhan N  Dou C  Huang H  Han Y  Yu D  Hu Y 《Biotechnology journal》2010,5(11):1186-1191
Bio-ethanol dehydration to ethylene is an attractive alternative to oil-based ethylene. The influence of fusel, main byproducts in the fermentation process of bio-ethanol production, on the bio-ethanol dehydration should not be ignored. We studied the catalytic dehydration of bio-ethanol to ethylene over parent and modified HZSM-5 at 250°C, with weight hourly space velocity (WHSV) equal to 2.0/h. The influences of a series of fusel, such as isopropanol, isobutanol and isopentanol, on the ethanol dehydration over the catalysts were investigated. The 0.5%La-2%PHZSM-5 catalyst exhibited higher ethanol conversion (100%), ethylene selectivity (99%), and especially enhanced stability (more than 70 h) than the parent and other modified HZSM-5. We demonstrated that the introduction of lanthanum and phosphorous to HZSM-5 could weaken the negative influence of fusel on the formation of ethylene. The physicochemical properties of the catalysts were characterized by ammonia temperature-programmed desorption (NH(3)-TPD), nitrogen adsorption and thermogravimetry (TG)/differential thermogravimetry (DTG)/differential thermal analysis (DTA) (TG/DTG/DTA) techniques. The results indicated that the introduction of lanthanum and phosphorous to HZSM-5 could inhibit the formation of coking during the ethanol dehydration to ethylene in the presence of fusel. The development of an efficient catalyst is one of the key technologies for the industrialization of bio-ethylene.  相似文献   

18.
Static tests were employed to assess the acute toxicity of the water-soluble fraction (WSF) of spent automotive lubricating oil (of mixed SAE grades) on Clarias gariepinus, a freshwater fish commonly cultured in Nigeria. Median lethal concentrations (LC50) of the WSF were found to decrease as a function of exposure time from 690+/-21 (after 24 h) to 513+/-58 mg/l (after 96 h). The characteristics of the WSF such as mean acidity (pH 6.6), turbidity (40 NTU), total dissolved solids (TDS; 40 mg/l) and significantly reduced (P<0.05) dissolved-oxygen (DO) values (1.44 mg/l) were not compliant with existing standards set for discharged effluents. The solubility of the detected straight-chain aliphatics ranked as C14>C16>C32>C18>C28; that of the simple aromatics was ortho-xylene>para-xylene; and that of the polyaromatic hydrocarbons (PAHs) was acenaphthylene>9H-fluorene>naphthalene>anthracene>phenanthrene>chrysene>benzo[k]fluoranthene>benzo[a]pyrene>benzo[b]fluoranthene, most of which being serious carcinogens. These oil constituents and the overall physico-chemical properties of the WSF are expected to act synergistically on the test organism (C. gariepinus), eliciting the quantal responses observed. The toxicity of the WSF points to the base constituent, oxidative degradation, and mechano-chemical reactions associated with aged crankcase oils. These oils, therefore, should definitely no longer be disposed into water streams or landscape, not even at sub-lethal concentrations, because of the inherent toxicity of their soluble fractions and the associated danger of bioaccumulation.  相似文献   

19.
The catalytic cracking of waste cooking palm oil to biofuel was studied over different types of nano-crystalline zeolite catalysts in a fixed bed reactor. The effect of reaction temperature (400-500 °C), catalyst-to-oil ratio (6-14) and catalyst pore size of different nanocrystalline zeolites (0.54-0.80 nm) were studied over the conversion of waste cooking palm oil, yields of Organic Liquid Product (OLP) and gasoline fraction in the OLP following central composite design (CCD). The response surface methodology was used to determine the optimum value of the operating variables for maximum conversion as well as maximum yield of OLP and gasoline fraction, respectively. The optimum reaction temperature of 458 °C with oil/catalyst ratio=6 over the nanocrystalline zeolite Y with pore size of 0.67 nm gave 86.4 wt% oil conversion, 46.5 wt% OLP yield and 33.5 wt% gasoline fraction yield, respectively. The experimental results were in agreement with the simulated values within an experimental error of less than 5%.  相似文献   

20.
A sensitive and rapid method to analyse fuel components in blood from rats exposed to kerosene or light oil vapour was developed by making use of capillary gas chromatography/mass spectrometry. The aliphatic hydrocarbons with carbon numbers 8-10 and aromatics such as toluene, xylene, 3- and 4-ethyltoluene and trimethylbenzenes were clearly detected in blood from rats exposed to kerosene or light oil vapour, using the head-space method combined with the salting-out technique. The concentration ratio of pseudocumene to toluene in blood exposed to light oil was higher than that in the case of exposure to kerosene. The lower limits of detection were 50 pg and 1 ng in toluene and pseudocumene, respectively. Our suggestion is that this method is useful in forensic investigations to detect fuel components in blood and for the purposes of differentiating kerosene and light oil in blood tissues.  相似文献   

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