摘要:
Methods and systems for efficiently manufacturing modified asphalt materials include agitating a base asphalt at a high shear rate using an in-line mixer equipped with a rotor-stator mixing tool while simultaneously exposing the asphalt to oxygen by blowing an oxygen-containing gas at a high gas flow rate through openings in the rotor-stator mixing tool and heating the asphalt at an elevated temperature.
摘要:
A method for preparing a modified optically isotropic pitch comprising, preparing a synthetic pitch by reacting a member selected from the group consisting of a conjugated polycyclic hydrocarbon containing a low molecular weight alkyl group or a material containing such a substituted hydrocarbon in the presence of hydrofluoric acid/boron trifluoride, and treating the synthetic pitch by passing an oxidizing gas through the synthetic pitch at elevated temperatures.
摘要:
An optically isotropic pitch can be obtained by a two-stage heat-treatment which combines a heat treatment with air-blowing under normal pressure with a heat treatment with air-blowing under a reduced pressure. Such a pitch is suitable for using as a raw material for producing carbon fibers or activated fibers.
摘要:
A process for converting the acid sludge produced by waste oil refineries into an acid sludge intermediary which can be used in the production of asphaltic mixtures. The process includes contacting the entire surface area of acid sludge with a pH altering agent such as an aqueous inorganic liquid, and separating the liquid layer from the sludge layer, thereby producing an intermediate sludge having properties which make it suitable for use in asphalt production.
摘要:
A process for preparing a paving asphalt cement comprising two steps. In the first step, a high quality paving asphalt precursor, a low quality paving asphalt precursor, a non-paving asphalt precursor or a mixture thereof are catalytically oxidized to form a paving asphalt cement. In the second step, the catalytically oxidized paving asphalt cement is mixed with one or more of a high quality paving asphalt precursor, a low quality paving asphalt precursor, a non-paving asphalt precursor or a mixture thereof.
摘要:
A carbon powder is disclosed with 40 to 75% by weight QI or more than 90% by weight TI, an optical anisotropy of less than 50% by volume, a start of softening between 200.degree. and 300.degree. C., and an oxygen content of more than 2% by weight, and which can be used for without binding agent the production of shaped carbon bodies. The carbon powder is produced by means of distillation from bituminous product at a maximum of 5 mbars and a final temperature of at least 400.degree. C., grinding of the distillation residue to a particle size of less than 30 .mu.m, and oxidation of the powder into the particle core.
摘要:
The process permits to produce bitumens having a high penetration value by oxidation of base bitumens with small volumes of gaseous oxidizers, preferably air, at a temperature between 170.degree. and 250.degree., preferably 200.degree. C., by turbodispersion of the gaseous phase in the bituminous mass by means of a rapid turbodisperser.By adding appropriate fluxes and operating in the presence of catalysts, the technological characteristics of the end product can be varied until obtaining blends of bitumens that are adapted for new applications.The turbodisperser is provided with an impeller constituted by a plane disk carrying on its periphery a series of teeth made preferably with the active side located on the diameter of the impeller and the angle at the vertex greater than 45.degree..
摘要:
An improved process for producing an anisotropic pitch product suitable for carbon fiber manufacture. A carbonaceous feedstock substantially free of mesophase pitch is heated for a period of time at an elevated temperature while passing an oxidatively reactive sparging gas such as a mixture of oxygen and nitrogen through the feedstock. The oxidatively treated feedstock is then subjected to a heat soak, for a longer period of time in the absence of a sparging gas. Thereafter the heat soaked feedstock is heated at an elevated temperature in the presence of a non-oxidative sparging gas for a time period equal to or less than the heat soak to produce an anisotropic pitch having from 50 to 100% by volume mesophase which is suitable for producing good quality carbon fibers.
摘要:
An improved process for producing an anisotropic pitch product suitable for carbon fiber manufacture. A carbonaceous feedstock substantially free of mesophase pitch is heated at elevated temperature while passing an oxidatively reactive sparging gas such as air through the feedstock. The oxidatively treated feedstock, which contains isotropic pitch, is solvent fractionated to recover a solid pitch which on fusion becomes an anisotropic pitch product having from 50 to 100 percent by volume mesophase. In one aspect of the invention the carbonaceous feedstock is oxidatively treated in a melt phase at a lower temperature and the resulting isotropic pitch is then heated at a higher temperature in a melt phase in the presence or absence of a non-oxidative sparging gas prior to solvent fractionation.
摘要:
A process for producing a mesophase pitch by heating a carbonaceous pitch at 350.degree. to 550.degree. C. wherein the heat treatment is conducted while supplying a hydrogen donor to the pitch. The mesophase pitch thus produced has an excellent spinnability.