Abstract: Provided are plasma processes for producing graphene nanosheets comprising injecting into a thermal zone of a plasma a carbon-containing substance at a velocity of at least 60 m/s standard temperature and pressure STP to nucleate the graphene nano sheets, and quenching the graphene nanosheets with a quench gas of no more than 1000° C. The injecting of the carbon-containing substance may be carried out using a plurality of jets. The graphene nanosheets may have a Raman G/D ratio greater than or equal to 3 and a 2D/G ratio greater than or equal to 0.8, as measured using an incident laser wavelength of 514 nm. The graphene nanosheets may be produced at a rate of at least 80 g/h. The graphene nanosheets can have a polyaromatic hydrocarbon concentration of less than about 0.7% by weight.

Abstract: Provided are graphene nanosheets having a polyaromatic hydrocarbon concentration of less than about 0.7% by weight and a tap density of less than about 0.08 g/cm3, as measured by ASTM B527-15 standard. The graphene nanosheets also have a specific surface area (B.E.T.) greater than about 250 m2/g. Also provided are processes for producing graphene nanosheets as well as for removing polyaromatic hydrocarbons from graphene nanosheets, comprising heating said graphene nanosheets under oxidative atmosphere, at a temperature of at least about 200° C.

Abstract: There are provided reactive metal powder in-flight heat treatment processes. For example, such processes comprise providing a reactive metal powder; and contacting the reactive metal powder with at least one additive gas while carrying out said in-flight heat treatment process, thereby obtaining a raw reactive metal powder.

Abstract: There are provided reactive metal powder atomization manufacturing processes. For example, such processes include providing a heated metal source and contact the heated metal source with at least one additive gas while carrying out the atomization process. Such processes provide raw reactive metal powder having improved flowability. The at least one additive gas can be mixed together with an atomization gas to obtain an atomization mixture, and the heated metal source can be contacted with the atomization mixture while carrying out the atomization process. Reactive metal powder spheroidization manufacturing processes are also provided.

Abstract: A plasma atomization metal powder manufacturing process includes providing a heated metal source and contacting the heated metal source with the plasma of at least one plasma source under conditions effective for causing atomization of the heated metal source. The atomization may be carried out using a gas to metal ratio of less than about 20, thereby obtaining a raw metal powder having a 0-106 ?m particle size distribution yield of at least 80%. The process may further include aligning the heated metal source with the plasma of at least one plasma source. An atomizing system may include an alignment system positioned upstream of the plasma source and adapted to adjust an orientation of the metal source relative to the at least one plasma source.

Abstract: The invention relates to a method for depositing nanometric filamentary structures. The method comprises passing a gaseous phase comprising the nanometric filamentary structures through a space defined between at least two electrodes generating an electric field, for depositing the nanometric filamentary structures on at least one of the electrodes; and at least substantially preventing the deposited nanometric filamentary structures from bridging the electrodes during the deposition. The invention also relates to an apparatus for depositing nanometric filamentary structures as well as to methods and apparatuses for monitoring the production of nanometric filamentary structures.

Abstract: There is provided an apparatus for producing single-wall carbon nanotubes. The apparatus comprises a plasma torch having a plasma tube adapted to receive an inert gas and form an inert gas plasma; a feeder adapted to direct a carbon-containing substance and a metal catalyst towards said inert gas plasma so that the carbon-containing substance and the metal catalyst contact said inert gas plasma downstream of where said inert gas is introduced in said plasma tube, to thereby form a plasma comprising atoms or molecules of carbon and the atoms of said metal; and a condenser for condensing the atoms or molecules of carbon and the atoms of said metal to form single-wall carbon nanotubes.

Abstract: There is provided method for treating a gaseous phase comprising carbon filamentary structures having metal particles attached or linked thereto, for separating at least a portion of said carbon filamentary structures from said metal particles. The method comprises submitting said gaseous phase to a disturbance generated by an electric field, a magnetic field, ultrasounds, a turbulent gas stream, or combinations thereof, thereby reducing the amount of carbon filamentary structures having metal particles attached or linked thereto.

Abstract: The invention relates to a method for depositing nanometric filamentary structures. The method comprises passing a gaseous phase comprising the nanometric filamentary structures through a space defined between at least two electrodes generating an electric field, for depositing the nanometric filamentary structures on at least one of the electrodes; and at least substantially preventing the deposited nanometric filamentary structures from bridging the electrodes during the deposition. The invention also relates to an apparatus for depositing nanometric filamentary structures as well as to methods and apparatuses for monitoring the production of nanometric filamentary structures.

Abstract: The invention relates to a method for monitoring the production of nanometric filamentary structures. The method comprises passing a gaseous phase comprising nanometric filamentary structures through a space defined between at least two electrodes generating an electric field for causing an increase of current between the electrodes and analyzing behavior of the current over a predetermined period of time and/or analyzing at least one of the size, density and shape of the nanometric filamentary structures or aggregates thereof present in the gaseous phase.

Abstract: The invention relates to a macroscopic assembly of nanometric filamentary structures. The macroscopic assembly comprises a plurality of microscopic assemblies substantially aligned in a same direction and connected together. Each of the microscopic assemblies comprises a plurality of members defining a plurality of spaces therebetween. Each of the members comprises a nanometric filamentary structure or a bundle of nanometric filamentary structures, wherein the macroscopic assembly has a density of less than 8 mg/cm3. The is also provided a method for preparing such a macroscopic assembly.

Abstract: The invention relates to a method for depositing nanometric filamentary structures. The method comprises passing a gaseous phase comprising the nanometric filamentary structures through a space defined between at least two electrodes generating an electric field, for depositing the nanometric filamentary structures on at least one of the electrodes; and at least substantially preventing the deposited nanometric filamentary structures from bridging the electrodes during the deposition. The invention also relates to an apparatus for depositing nanometric filamentary structures as well as to methods and apparatuses for monitoring the production of nanometric filamentary structures.

Abstract: There is provided a method for purifying carbon filamentary structures contaminated with magnetic metal particles. The method comprises submitting a gaseous phase comprising said carbon filamentary structures contaminated with magnetic metal particles, to an inhomogeneous magnetic field for at least partially trapping said magnetic metal particles, thereby reducing the proportion of said magnetic metal particles present in said gaseous phase. The method is particularly useful for purifying carbon filamentary structures such as multi-wall carbon nanotubes, single-wall carbon nanotubes or carbon fibers. An apparatus for purifying such carbon filamentary structures contaminated with magnetic metal particles is also provided.

Abstract: The invention relates to a macroscopic assembly of nanometric filamentary structures. The macroscopic assembly comprises a plurality of microscopic assemblies substantially aligned in a same direction and connected together. Each of the microscopic assemblies comprises a plurality of members defining a plurality of spaces therebetween. Each of the members comprises a nanometric filamentary structure or a bundle of nanometric filamentary structures, wherein the macroscopic assembly has a density of less than 8 mg/cm3. The is also provided a method for prerparing such a macroscopic assembly.