摘要:

Recovery of organic material from Israeli Mishor Rotem oil shale with toluene under supercritical conditions was investigated. The rate of solubilization, change of structural aspects and molecular weights of solubilized products with time were investigated. Experiments to recover organic material from shale were performed in a stainless steel high pressure autoclave. Shale Sample was charged in a sintered glass crucible suspended from the cap of the autoclave; toluene was the solvent in all experiments. Solvent/shale ratio was 20; experimental temperature was 34O°C. The gaseous products were analyzed by gas chromatography. Molecular weights of the organic material recovered was measured by gel permeation chromatography technique. FTIR spectra of the organic material recovered and fractions isolated by extractive and chromatographical methods were measured. The amount of kerogen remaining in the spent shale was determined by oxidative derivative thermal gravimetry. A steady state in the production of solubles was reached within 60 minutes at 340°C with a yield of 60 percent. After this time no further amounts of organic material was recovered. The molecular weights of the recovered organic material decreased at extended times after the steady state was reached. It appeared that the structure of the organic material recovered remained unchanged until the steady state condition is reached whereupon some structural changes occurred. At extended times the organic material was converted into more aromatic and less hydroxyl containing structures of lower molecular weight. The organic material recovered upon reaching steady state was fractionated into 63 percent oils (pentane solubles) and 32 percent asphaltenes (toluene solubles). The oile contained aliphatics and monoaromatic structures and the asphaltenes contained polyaromatic polar structures. Gases which constituted 4 percent of the initial kerogen were produced during the heating period to 340°C. The amount of carbon monoxide produced remained constant and amounts of hydrogen, carbon dioxide and methane decreased after supercritical conditions were attained.

ISSN:0884-3759    

DOI:10.1080/08843758608915825

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The Dean and Stark distillation is an appropriate method for the determination of water in coal tar, bitumen and petroleum-like products. This article shows, however, that a direct application of the Dean and Stark method for the determination of water in biomass-derived liquid fuels results in incorrect estimates. Inaccuracies are due to the presence of soluble organics in the aqueous phase, which apparently form azeotropic mixtures with water and xylene and which condense and are trapped as distillate in the graduated cylinder. Instead, a Karl Fischer determination of water is recommended in the case of biomass-derived liquid fuels

ISSN:0884-3759    

DOI:10.1080/08843758608915826

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Little is understood about the unsteady-state flow of coal water fuels such as shear stress growth after the onset of a sudden shear rate. The theories in the literture are not always able to predict for example, stress growth at a given constant shear rate from data obtained on other experiments. A rheologlical model was developed to be able to adequately represent data in the time domain. The results of our analysis revealed that three parameter model, provides an execellent description of the transient behavior of dense/coal water fuels. The theory was tested and found to compare well to the experimental data.

ISSN:0884-3759    

DOI:10.1080/08843758608915827

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Kinetics of non-catalytic liquefaction of Seyitomsr lignite has been investigated under hydrogen pressure, using tetralin as a Bolvent in a laboratory Bcale batch autoclave reactor.

ISSN:0884-3759    

DOI:10.1080/08843758608915828

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Rates of molecular oxygen consumption at 23°C and 1 atm O2by a coal-derived middle distillate containing cyclohexanol and other additives are reported. Significant inhibition of fuel oxidation was observed in the presence of 0.15% w/w benzylidene benzoylhydrazine, HBBz, but was not observed if the fuel had first been treated with pentane to precipitate gum and the predominant metals. Gum precipitated in the presence of HBBz had a higher S content than in its absence. Equilibria between HBBz, metals in the fuel and catalyst X (which may contain sulfur) are suggested to account for inhibition of fuel oxidation by HBBz.

ISSN:0884-3759    

DOI:10.1080/08843758608915829

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

We analyzed thermally treated heavy residua by element specific size exclusion chromatography (SEC-ICF) to elucidate the fate of the V and Ni compounds. Thermal treatment, in addition to removing metals, significantly reduces the size of the remaining metal-containing compounds.We thermally treated the distillable and nondistillable metals separately. The distilled metals, primarily petroporphyrins, were completely removed under moderate conditions. The non-volatile metal-containing components, which constituted most of the Ni and V, were either removed, or reduced in size.when treating heavy residua over commercial fixed-bed hydroprocessing catalysts, the metal-containing molecules in the size range of the catalyst pore are preferentially removed. Those larger than the pore size appear to demetalate more slowly.The results argue demetalation is a function of the ligand structure and size of the metal-containing species and not necessarily the coordination sphere around the metal center.

ISSN:0884-3759    

DOI:10.1080/08843758608915830

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A mixed 450°C+ vacuum residue obtained from Austra-rian brown coal-derived oil with hydrogenated creosote oil was hydrogenated to elucidate the effect of catalyst mesopore diameter on the activities of Ni-Mo-γ-Al2O3 catalysts. Catalyst activities, especially for the heavy fraction in feedstock, were evaluated mainly by the conversion of 350°C+ residue to 35O°C −oil (HDC), hydrodesulfurization (HDS) and hydrodenitrogenation (HDN). These decreased in the order of HDS > HDN > HDC; whereas the deactivation rate during 50 hours on stream decreased in the order of HDC > HDN > HDS due to carbonaceous deposits on the catalyst. HDC, HDS and HDN rates per unit surface area of catalyst indicated that the HDS reaction was more strongly influenced by pore diffusion than the HDN and HDC reactions. The heavy ends in feedstock (such as asphaltenes) contained higher amounts of oxygen and nitrogen compounds. These polar compounds tended to be accumulated on the catalyst surface as the precursors for the formation of carbonaceous material deposits. The profile of carbon inside catalyst particle indicated that mesopore size of 22.6 nm might be satisfactory for reactant molecules to diffuse to the center of catalyst particle and access all of the active sites effectively.

ISSN:0884-3759    

DOI:10.1080/08843758608915831

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor