Having step or means utilizing chemical property
July 31st, 2009 | by Ramaswami |Counter current mixing reactor
A mixing reactor for mixing efficiently streams of fluids of differing densities. In a preferred embodiment, one of the fluids is supercritical water, and the other is an aqueous salt solution. Thus, the reactor enables the production of metal oxide nanoparticles as a continuous process, without any risk of the reactor blocking due to the inefficient mixing inherent in existing reactor designs.
Method for making silica nanoparticles by flame spray pyrolysis adopting two-fluid nozzle
The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.
Nickel oxide nanoparticles as catalyst precursor for hydrogen production
Decomposition of methane to produce carbon monoxide-free hydrogen is accomplished using un-supported, nanometer sized, hydrogen reduced, nickel oxide particles made by a precipitation process. A nickel compound, such as NiCl.sub.2 or Ni(NO.sub.3) is dissolved in water and suitably precipitated as nickel hydroxide. The precipitate is separated, dried and calcined to form the NiO catalyst precursor particles.
Process for functionalizing carbon nanotubes under solvent-free conditions
The present invention provides methods by which carbon nanotubes can be functionalized under solvent-free conditions. As extremely large quantities are typically required to dissolve or disperse carbon nanotubes, solvent elimination the processes more favorable for scale-up. Such processes are also amenable to a wide variety of chemical reactions are functionalizing agents.
Manufacture of silica aerogel via vapor phase reaction
A kinetically controlled vapor reaction process for synthesizing silica areogel in a reaction container by injection of a precursor reagent vapor, a catalyst reagent vapor, super saturated steam as a component of the catalyst solution, and a hydrophobic reagent vapor amd continuously mixing vapor droplets of the precursor, catalyst and water reagents in a super saturated state to continuously nucleate in a hydrolysis/poly-condensation reaction and deposit as silica aerogel.


Sorry, comments for this entry are closed at this time.