Device and method for converting carbon containing feedstock into carbon containing materials having a defined nanostructure

Abstract

Apparatus and process for producing carbon black or carbon containing compounds by converting a carbon containing feedstock, comprising the following steps: generating a plasma gas with electrical energy, guiding the plasma gas through a venturi, whose diameter is narrowing in the direction of the plasma gas flow, guiding the plasma gas into a reaction area, in which under the prevailing flow conditions generated by aerodynamic and electromagnetic forces, no significant recirculation of feedstock into the plasma gas in the reaction area recovering the reaction products from the reaction area and separating carbon black or carbon containing compounds from the other reaction products.

Description

[0001]This application is a divisional of U.S. patent application Ser. No. 10 / 380,647, now U.S. Pat. No. 7,452,514, which has a § 371 compliance date of Sep. 22, 2003, which is the U.S. national phase of international patent application No. PCT / EP01 / 10835 (WO 02 / 24819 A1), filed Sep. 19, 2001, which claims priority to European Patent App. No. 00120115.1, filed Sep. 19, 2000, all of which are incorporated herein by reference in their entireties for all purposes.TECHNICAL FIELD[0002]A process and an apparatus are disclosed for converting carbon containing feedstock into carbon black or other carbon containing materials, having a defined nanostructure.[0003]More than 99% of the carbon black is presently produced by incomplete combustion processes. By far, the dominant process is a furnace process developed sixty years ago. Other processes include channel, thermal and lamp processes. All these industrial processes are characterized by the combustion of about 40% to 60% of the feedstock ...

AI Technical Summary

Benefits of technology

[0007]A process and apparatus are disclosed for producing carbon black with well-defined properties, allowing control of operating conditions and process parameters to obtain high conversion efficiency of feedstock and reproducible product quality.

[0009]The control of the operating conditions for the production of carbon black with well-defined properties includes the preventing of circulation of the feedstock and any products through the arc zone thus producing carbon black materials with well defined and consistently reproducible properties. In particular a venturi allows a better control of the reaction temperature and a more efficient mixture in the “low temperature region” of the reaction zone, where the carbon black is produced.

[0013]The plasma gas is injected into the reactor space, not necessarily through the plasma arc. In a preferred embodiment, the electric arc is a compound arc, created by at least three electrodes. Preferably, the electrodes are graphite based electrodes and the arc is created by connecting a sufficient AC power source to the electrodes. The current frequency can be the frequency of the grid using a conventional power source (50-60 Hz) or it can be higher using a high frequency power switching source. An increase in the frequency can increase the arc stability, particularly when using hydrogen as the plasma gas. In this case, the current frequency is preferably between 500 Hz to 10 kHz.

[0014]The venturi preferably is made from a graphite based material and is formed as a cone. The downstream side of the venturi is preferably formed as an edge and therefore building an abruptly expanding zone. An edge between the throat and the abruptly expanding zone causes an abrupt expansion of the plasma gas volume. This is the preferred means to prevent back-flow of carbon containing material into the area upstream of the venturi zone outlet, particularly into the plasma forming region, e. g., into the arc or arcs. The expanding zone also generates a high turbulence zone in the flow that is used to increase the mixing efficiency between the plasma flow and the feedstock and to realize a homogeneous mixture and a better control of the reaction temperature.

[0030]The disclosed carbon black has the advantage of having a low density. In, e. g., tire applications, this results in a reduction of the needed weight of carbon black and in an overall weight reduction of the final rubber product. Another application of the new carbon blacks lies in dry cell electrodes.

Problems solved by technology

Further, the production of new materials is limited by the process chemistry, i.e., chemical composition and available energy.

No evidence has been given that these processes can produce carbon black on a commercial scale.

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