Dear all Thank you for your interest in our work and your comments. To clarify some of the misunderstanding in the process conditions that I'd like to clarify. When we bubble CO2 in water with and without the nanoparticles, we observed that there is more CO2 in the nanoparticle system than in pure water. We also observed that there was HCO3- ions on the surface of the Ni nanoparticles surface, we thus explained that this enhancement could be due to adsorption of the HCO3- (from the acid) onto the Ni surface. We in no place claim the formation of CO3-- ions, to be clear on this point the system we are addressing in this article is at a acidic pH (<5). Thus there is only carbonic acid species present no bicarbonate or carbonate system as they exist at higher pH values.
Now coming to the point of mineralization. We are currently working on this (as explained by Dr Siller, previously) and would like to use silicates as our metal source (Ca2+ or Mg2+). Regarding the confusion of sea or oceanic system. We do not tend to imply the use of Ni nanoparticles in the ocean or any thing around it. The relation with sea urchin (or the marine environment) is just that, the use of Ni to study the hydration reaction we triggered by the studies done on the sea urchin by Dr Siller and my other colleagues. Our major application is to use this system as a satellite unit (plant) to an operational point source emitter (for example a power plant). The carbonate mineral thus produced would be used as landfill or in any other useful application. As mentioned above, we are working on the use of silicate sources (terrestrial) for the source of the alkali earth metals (Ca2+ or Mg2+), thus ruling out acidification of the ocean or any relation to the ocean. Hope I was able to explain the application of our technology. If you still have any doubts, please feel free to ask. We will try our level best to clarify any confusion. Thanks to all Kind regards Gaurav On Thursday, 7 February 2013 18:49:41 UTC, Greg Rau wrote: > > Thanks for responding. I really don't follow this. If I have a beaker > of water fully equilibrated with air (CO2) and add your Ni particles, you > are saying that more HCO3- and ultimately CO3s will spontaneously be > produced. This won't happen unless thermodynamically favored, and if that > water if fully equilibrated with air CO2 there is no thermodynamic > condition that will force a change in the C chemistry. If your Ni > particles are somehow consuming H+ or producing OH- then you've got a > driving force, but you still need a source cations to make CaCO3s (am > very interested to learn how you cheaply extract cations from silicates.) > Otherwise, adding a catalyst to a system at thermodynamic equilibrium does > nothing. On the other hand, adding something to seawater that overcomes > the natural, chemical inhibition of abiotic CaCO3s precipitation could > really cause some serious precipitation and CO2 injection into the > atmosphere. No? > -Greg > > From: "[email protected] <javascript:>" <[email protected]<javascript:> > > > Reply-To: "[email protected] <javascript:>" > <[email protected]<javascript:> > > > Date: Thursday, February 7, 2013 8:32 AM > To: geoengineering <[email protected] <javascript:>> > Subject: [geo] Re: Nickel nanoparticles catalyse reversible hydration of > carbon dioxide for mineralization carbon capture and storage - Catalysis > Science & Technology (RSC Publishing) > > > With presence of Ni we have increases at the same time trapping of CO2 > and increased the rates of conversion to carbonic acid on room temperature > and on the atmospheric pressure. > We still working to find the best mineralisation pathway - we will use > silicates (magnesium calcium silicates) as a source of Ca2+ or Mg2+. > > While nickel nanoparticles are toxic as already mentioned in the paper we > do not propose to spread this around in the enviroment but to have local > disposal next to power plant or industrial plant. > We made brief cost - 8$ per ton of CO2 if we can recover Ni 99% yield > based on current price of nickel. > > > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > To post to this group, send email to [email protected]<javascript:> > . > Visit this group at http://groups.google.com/group/geoengineering?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
