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kclo4
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It has to be more then 20mg/L (aka 20ppm) since the problem with fish tanks is that it can get to high (past 100ppm) that is 100mg/L. I am doing the
ppm conversion correctly right?
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not_important
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NO3 is much heavier than H2O, it's not a 1:1 equivalence.
The conversion of nitrate to nitrogen, by denitrifying bacteria, shuts down before the nitrifying bacteria do. The production of nitrate starts to
slow down in the 10 to 20 range, but may continue increasingly slowly to higher concentrations, from what I read. As conversion is slow anyway,
pushing into the still slower range seems to be less than desirable.
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kclo4
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Oh I see, so I have done the ppm(mg/L) to grams wrong?
could you explain to me how exactly it is done then?
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Formatik
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I've got some more info on the oxidation of KCNO, but I don't know how well this side discussion fits in this thread mostly covering nitrification
reactions.
I've included the bit about KCN for saftey reasons, it needs sufficient air. Heating to 700 to 900º (2-4 hrs) KCNO partially converts to KCN. The
maximum of KCN (per 100 g reaction product) is 53.08 g KCN is obtained after 2 hrs at 900º (C.r. 161 [1915] 308).
About 3 hours heating of KCNO in a well dried stream of air oxidizes it to KNO3, the oxidation is accelerated through catalysts such as metallic Cu,
Ni, Ag, Au or their salts, as well as traces of moisture in the air stream, where KCNO is primarily split into easily oxidizable NH3 and K2CO3 (Ber.
59 [1926] 210).
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chief
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I now found: The N-content of _peas_ is 6.25 %; also in big amounts (25 kg) they should be very cheap (50 % more expensive than wheat)
==> everybody may have seen, how quickly a pea-soup is gonna be the breeding ground of zillions of bacteriae !
The stuff contains maybe averything that any microorganism might like, so:
Why not make a pea-soup (100 l), give the right bacteriae into it and see the result ?
Unfortunately I have _no_ experience in anything microorganism-related, so I wouldn't know how to find the right bacteriae, but probably from where
they should occur in nature ...
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kclo4
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| Quote: | Originally posted by Formatik
I've got some more info on the oxidation of KCNO, but I don't know how well this side discussion fits in this thread mostly covering nitrification
reactions.
I've included the bit about KCN for saftey reasons, it needs sufficient air. Heating to 700 to 900º (2-4 hrs) KCNO partially converts to KCN. The
maximum of KCN (per 100 g reaction product) is 53.08 g KCN is obtained after 2 hrs at 900º (C.r. 161 [1915] 308).
About 3 hours heating of KCNO in a well dried stream of air oxidizes it to KNO3, the oxidation is accelerated through catalysts such as metallic Cu,
Ni, Ag, Au or their salts, as well as traces of moisture in the air stream, where KCNO is primarily split into easily oxidizable NH3 and K2CO3 (Ber.
59 [1926] 210). |
I doubt heating KOCN produces KCN. How would it?
With a reducer, of course.. but by itself? Seems unlikely.
I know KCN is oxidized in the air to KOCN.
Oh yeah, and I do like the Idea of oxidizing KOCN into KNO3, Any idea on how hot it would have to get?
[Edited on 8-11-2008 by kclo4]
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Formatik
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That bit about KCN is just heating by itself. I don't know what temperatures are needed since I haven't looked at the references, my likely guess is
between 200 to 500º.
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kclo4
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I think at those tempuratures you might have problems with KNO3 decomposing, but perhaps not 
400 °C is the decomposition temperature of KNO3, if it decomposes at those temperatures, I imagine it would be very hard to form it around those
temperatures as well.
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Formatik
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Quote: Originally posted by Formatik  | | About 3 hours heating [at 400 deg.] of KCNO in a well dried stream of air oxidizes it to KNO3, the oxidation is accelerated through catalysts such as
metallic Cu, Ni, Ag, Au or their salts, as well as traces of moisture in the air stream, where KCNO is primarily split into easily oxidizable NH3 and
K2CO3 (Ber. 59 [1926] 210). |
The yields by this method are disappointing for sure, type of catalyst has an influence and with Ag powder the yield was highest at 22% of the
nitrogen and slightly moist air, compared to Cu, Ni powder or their compounds. Oxidizing KCNO with KClO3 which has to be diluted with Na2CO3 or CaO
(to avoid explosion) gets a better yield of 37.4% of the N, but still quite low. Another method uses CaCN2. Technical CaCN2 heated with Na2CO3 and
small amount of catalyst under stirring under moderatley fast air stream at 400 deg., converts "the largest part" of the bound nitrogen to nitrate
(DE439510). I've also got the Ber. 59 [1926], 204-212 ref., it's in my profile. It's quite interesting. Oxidizing CaCN2 or urea with solid inorganic
peroxides has potential as the nitrate yield is modestly high, though requires large amounts of peroxides, e.g. deflagration of CaCN2 with Na2O2 gets
65% of the N yield.
Attachment: DE439510.pdf (79kB)
This file has been downloaded 995 times
[Edited on 24-5-2009 by Formatik]
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S.C. Wack
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I see that the <1 MB pdf attachment on my last post has disappeared somehow. That's not a good sign. Not only can I not upload pdfs, old ones are
disappearing....
While I'm here, a working link to the Gallica article (long, old, French), since Gallica has changed some lately and the link I gave before is not so
great now
http://gallica.bnf.fr/ark:/12148/bpt6k34941m.image.f431
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Big Boss
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I'm running an experiment at the minute where I have gotten some of soil, added 0.75% NH4Cl sol to it and let the bacteria reproduce for a few days in
some soil, then after about 3 days I washed the soil with more NH4Cl sol and transferred it to a 2L bottle with 1L of 0.75% sol in it.
I added powdered CaCO3 to it to neutralise any Nitric Acid formed during the process forming Calcium Nitrate.
I added an aquarium bubbler to it. So far it has been 2 days and this morning I took a small sample of the liquid and added NaOH solution to it, of
course I could smell Ammonia indicating that all of the NH4Cl has not been fermented yet, however I also got a very fine precipitate of presumably
Ca(OH)2.
The bacteria apparently take days to reproduce, they must consume a lot of ammonia before doing so.
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Melgar
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Actually, nitrate-selective ion exchange resin would be perfect for this project. It's already a mass-produced commodity, and can be reused
indefinitely.
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10fingers2eyes
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nitrifying bacteria
I am in the midst of trying this using aquarium bacteria to produce nitrates from urea. My set up is a 5 gallon jug with a small aquarium air pump,
small aquarium heater (82F) and moving bed filter media to maximize surface area for the bacteria to grow on. It takes at least a week or two just to
get enough bacteria growing to get the moving bed media to circulate. I have been running for 6 weeks now and I have a positive test for at least a
few grams of nitrates, it is just starting to barely indicate on a brown ring test, very slow but most of the time has been bacteria colony
establishment at this point. I feed it about 5 g of urea a day and have some trace nutrients initially like phosphate, potassium, iron, calcium and
magnesium. Urea is good food because the bacteria can hydrolyze it and use the CO2 for a carbon source as well. Getting enough oxygen to dissolve at
some point might be a problem.
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Tsjerk
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Any idea what species you have growing in there?
Edit: | Quote: | | Wiki: Nitrification inhibitors are chemical compounds that slow the nitrification of ammonia, ammonium-containing, or urea-containing fertilizers,
which are applied to soil as fertilizers. These inhibitors can help reduce losses of nitrogen in soil that would otherwise be used by crops.
Nitrification inhibitors are used widely, being added to approximately 50% of the fall-applied anhydrous ammonia in states in the U.S., like
Illinois.[16] They are usually effective in increasing recovery of nitrogen fertilizer in row crops, but the level of effectiveness depends on
external conditions and their benefits are most likely to be seen at less than optimal nitrogen rates.[17] |
Are you sure your urea doesn't contain an inhibitor?
[Edited on 24-1-2017 by Tsjerk]
[Edited on 24-1-2017 by Tsjerk]
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Σldritch
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I am currently growing bacteria in 30L of tap water and 500ml of granulated urea and three flower food sticks for phosphorous and micronutrients. It
is hard to tell if it has changed but it strongly smells of ammonia so i think something is happening in there.
How concentrated amonium nitrate solution can the bacteria survive in?
There is this source but i have no idea if it is accurate: http://www.bioconlabs.com/nitribactfacts.html
[Edited on 23-11-2017 by Σldritch]
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NEMO-Chemistry
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Once Nitrate reaches a certain level, Nitrosomas uses it and starts to reverse it back to Nitrite and Ammonia. There is a paper somewhere on my pc
about it.
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Σldritch
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Do they really if the suspension is still aerated? They should gain no energy from that, right? Maybe something will start oxidizing the dead cells
for energy or something photosynthetic starts growing in but that should not be a problem.
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Metacelsus
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Bacterial nitrate reduction primarily happens under anaerobic conditions (at least for the Rhodobacterales, which are the most important for this, and
probably for all the other denitrifying bacteria as well). Under aerobic conditions, oxygen is preferentially used as a terminal electron acceptor,
although a small amount of denitrification can also happen.
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NEMO-Chemistry
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| Quote: Originally posted by Metacelsus | | Bacterial nitrate reduction primarily happens under anaerobic conditions (at least for the Rhodobacterales, which are the most important for this, and
probably for all the other denitrifying bacteria as well). Under aerobic conditions, oxygen is preferentially used as a terminal electron acceptor,
although a small amount of denitrification can also happen. |
The paper is on the laptop or would be easier to find, i kept it because i keep fish. Now its one paper, and it goes against everything i ever thought
about filtration and fish.
I had always assumed anaerobic conditions and different bacteria to revert Nitrate. But i will search it out, i would be extremely interested to get
real chemists opinions on the paper.
From memory it was Nitrosomas (99% sure) and aerobic (85% sure). I cant remember the conditions needed but i was more than surprised. Personally I
have doubts, but as soon as i dig it up i will post.
My first thought i admit was, total tosh. But let me find it and see what you think.
I dont have mendeley on the laptop, which is a PITA, but a quick look found this..
http://eawag-bbd.ethz.ch/nit/nit_map.html
This however is not what i found in the other paper. But until i find it again, maybe someone can spot something that makes sense in what I was
saying.
The link is on about anaerobic conditions, however I am positive the other paper mentions aerobic conditions and very high levels of Nitrate.
[Edited on 28-11-2017 by NEMO-Chemistry]
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Metacelsus
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| Quote: Originally posted by NEMO-Chemistry |
From memory it was Nitrosomas (99% sure) and aerobic (85% sure). I cant remember the conditions needed but i was more than surprised. Personally I
have doubts, but as soon as i dig it up i will post.
|
Nitrosomonas (not "Nitrosomas") will oxidize ammonia to nitrite. Nitrobacter can then oxidize the nitrite further to nitrate. These
processes happen only when oxygen is present.
If both nitrite and ammonia are present simultaneously under anaerobic conditions, then some bacteria can convert them both to nitrogen gas (this is
known as anaerobic ammonia oxidation).
Denitrifying bacteria, such as Paracoccus, use nitrate for anaerobic respiration and reduce it to nitrogen gas. They do this primarily under
anoxic conditions.
My source for all this information is my Microbiology textbook (Prescott's, 9th edition).
Also, I can't load the site you linked to in the post above.
Edit: I found it on the web archive.
[Edited on 11-28-2017 by Metacelsus]
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NEMO-Chemistry
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| Quote: Originally posted by Metacelsus | | Quote: Originally posted by NEMO-Chemistry |
From memory it was Nitrosomas (99% sure) and aerobic (85% sure). I cant remember the conditions needed but i was more than surprised. Personally I
have doubts, but as soon as i dig it up i will post.
|
Nitrosomonas (not "Nitrosomas") will oxidize ammonia to nitrite. Nitrobacter can then oxidize the nitrite further to nitrate. These
processes happen only when oxygen is present.
If both nitrite and ammonia are present simultaneously under anaerobic conditions, then some bacteria can convert them both to nitrogen gas (this is
known as anaerobic ammonia oxidation).
Denitrifying bacteria, such as Paracoccus, use nitrate for anaerobic respiration and reduce it to nitrogen gas. They do this primarily under
anoxic conditions.
My source for all this information is my Microbiology textbook (Prescott's, 9th edition).
Also, I can't load the site you linked to in the post above.
Edit: I found it on the web archive.
[Edited on 11-28-2017 by Metacelsus] |
Sorry excuse my spelling.
I am aware of the normal way it works, as i said above the paper goes against everything i have read on it. The only other information i found was the
link above (i will try and find another).
The problem with the above link is it is Anaerobic. Dont shoot the messenger!  ,
i am more interested in what people make of the paper. Thats why i have avoided the whole what organism is actually responsible debate  .
I have asked around on a couple of fish forums i am on, no one knows anything about the paper..... Starting to hope i find it or a reference for it.
Link opens fine for me! But i have recently changed DNS servers because of 'other' issues...
[Edited on 28-11-2017 by NEMO-Chemistry]
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NEMO-Chemistry
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Cant find this paper at all now, so i withdraw what i said until i can back it up. Really annoying as it would have made a great subject to discuss!
but without the paper its just he said/ she said waffle. Sorry guys I was sure i knew where the paper was.
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