A remote plasma process for the treatment of particulate materials comprising: mixing of a process gas stream and a carrier gas stream in a treatment zone, wherein, before mixing, the process gas stream is enriched by excited gas species and the carrier gas stream is loaded with substrate particles; wherein an electrical gas discharge is applied to the process gas stream for the creation of a non-thennal plasma at atmospheric pressure or near the same whereof the electrons being used to generate active species in the process gas stream and wherein high velocities are superimposed upon the process gas stream prolonging the displacement distance of excited species and thus, enlarging the afterglow region of the said atmospheric plasma; wherein the zone/phase of the substrate particle treatment in the treatment zone is spatially and temporally separated from the production of said excited species such that the treatment zone and/or the treatment phase is located in the afterglow of the non-thermal plasma or downstream of this region; and wherein a homogenous, chemical reaction of the excited species on the surface of the substrate particles in said treatment zone takes place, characterized in that in the treatment zone the particle loaded carrier gas stream is guided along an axis, and in that the process gas stream enriched with excited species is guided to the treatment zone from a direction essentially perpendicular to said axis, or in a conical direction, in a converging manner wherein the process gas stream is guided to the treatment zone through at least one channel located in a plane perpendicular to said axis. mixing of a process gas stream and a carrier gas stream in a treatment zone, wherein, before mixing, the process gas stream is enriched by excited gas species and the carrier gas stream is loaded with substrate particles; wherein an electrical gas discharge is applied to the process gas stream for the creation of a non-thennal plasma at atmospheric pressure or near the same whereof the electrons being used to generate active species in the process gas stream and wherein high velocities are superimposed upon the process gas stream prolonging the displacement distance of excited species and thus, enlarging the afterglow region of the said atmospheric plasma; wherein the zone/phase of the substrate particle treatment in the treatment zone is spatially and temporally separated from the production of said excited species such that the treatment zone and/or the treatment phase is located in the afterglow of the non-thermal plasma or downstream of this region; and wherein a homogenous, chemical reaction of the excited species on the surface of the substrate particles in said treatment zone takes place, characterized in that in the treatment zone the particle loaded carrier gas stream is guided along an axis, and in that the process gas stream enriched with excited species is guided to the treatment zone from a direction essentially perpendicular to said axis, or in a conical direction, in a converging manner wherein the process gas stream is guided to the treatment zone through at least one channel located in a plane perpendicular to said axis.