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Topic: I will answer chemistry questions - page 3. (Read 8563 times)

sr. member
Activity: 440
Merit: 250
October 14, 2012, 05:31:14 PM
#20
OK, I still don't see why you would want to do the reverse-water-gas shift reaction when there are plenty of easier ways to go about getting CO.
I'm trying to revolutionize the world, of course (like any self-respecting scientist). And this is the part I'd like to keep secret for a while longer, though I'd say google could probably tell you why if you search around the topic a bit. And my masterplan requires me to generate CO from H2 and CO2; reduction of O2, CO2 or H2O with C is not an option.
hero member
Activity: 518
Merit: 500
October 13, 2012, 07:58:50 PM
#19
This is the water gas shift reaction:  H2+CO2 -> CO+H2O

Wait a minute, you are quoting the reaction in the reverse of what most people think of. This reaction is used industrially to produce hydrogen from methane (partial oxidation of methane, followed by the water gas shift). Are you trying to produce CO?

In the formation of hydrogen, one way to separate the hydrogen out is to pass it over a palladium membrane. The hydrogen will pass through the palladium, but the other species will not. Essentially the hydrogen reacts with the palladium to form palladium hydride, diffuses through the metal layer and reforms molecular hydrogen on the other side of the membrane. In this paper they describe the reaction being driven to the H2+CO2 side by removing the hydrogen through such a membrane.

It looks like there are several transition metals that will catalyze this reaction. Even gold. Many people on this forum like gold, perhaps they will find this interesting?

Yes, the reverse WGS reaction - I wish to generate CO. I sent you a PM about it. Just for anyone else listening - I know CO is abominably dangerous and no, I'm not trying to top myself. The 4 species would have some equilibrium ratio, dependent on T & P, so I would need a method for extracting the CO and H2O so as to favor their continued production - exactly the opposite of the article you cite.

I sent you a PM about it a couple of days ago, but I realize the PM notification is hardly noticeable.

OK, I still don't see why you would want to do the reverse-water-gas shift reaction when there are plenty of easier ways to go about getting CO.

Quote from: Wikipedia
A major industrial source of CO is producer gas, a mixture containing mostly carbon monoxide and nitrogen, formed by combustion of carbon in air at high temperature when there is an excess of carbon. In an oven, air is passed through a bed of coke. The initially produced CO2 equilibrates with the remaining hot carbon to give CO. The reaction of O2 with carbon to give CO is described as the Boudouard equilibrium. Above 800 °C, CO is the predominant product:
O2 + 2 C → 2 CO (ΔH = −221 kJ/mol)
Another source is "water gas", a mixture of hydrogen and carbon monoxide produced via the endothermic reaction of steam and carbon:
H2O + C → H2 + CO (ΔH = +131 kJ/mol)

For the second reaction, you could then pass the gas over the palladium membrane to remove the hydrogen, leaving pure CO.

I also found this webpage which describes a simple, easy way to generate pure CO on a benchtop scale. They just mix conc. sulfuric acid and formic acid, which dehydrates the formic acid, releasing CO.
HCOOH + cat. H2SO4 --> H2O + CO

I suppose I should think about where the gasses come from, but where I work we just order cylinders of gasses. In my lab we have big tanks of CO, H2, syngas(CO + H2, in 1:1 and 2:1 ratios), compressed air, N2, He, and CO2 all lined up in a row. We also have a very sensitive CO/CO2 monitor right above these tanks for safety.
sr. member
Activity: 440
Merit: 250
October 13, 2012, 03:41:32 PM
#18
This is the water gas shift reaction:  H2+CO2 -> CO+H2O

Wait a minute, you are quoting the reaction in the reverse of what most people think of. This reaction is used industrially to produce hydrogen from methane (partial oxidation of methane, followed by the water gas shift). Are you trying to produce CO?

In the formation of hydrogen, one way to separate the hydrogen out is to pass it over a palladium membrane. The hydrogen will pass through the palladium, but the other species will not. Essentially the hydrogen reacts with the palladium to form palladium hydride, diffuses through the metal layer and reforms molecular hydrogen on the other side of the membrane. In this paper they describe the reaction being driven to the H2+CO2 side by removing the hydrogen through such a membrane.

It looks like there are several transition metals that will catalyze this reaction. Even gold. Many people on this forum like gold, perhaps they will find this interesting?

Yes, the reverse WGS reaction - I wish to generate CO. I sent you a PM about it. Just for anyone else listening - I know CO is abominably dangerous and no, I'm not trying to top myself. The 4 species would have some equilibrium ratio, dependent on T & P, so I would need a method for extracting the CO and H2O so as to favor their continued production - exactly the opposite of the article you cite.

I sent you a PM about it a couple of days ago, but I realize the PM notification is hardly noticeable.
hero member
Activity: 518
Merit: 500
October 12, 2012, 11:36:56 PM
#17
How can I distinguish and separate the following 4 molecules which are in equilibrium at high temperature: H2, CO, CO2, H2O.

This is the water gas shift reaction:  H2+CO2 -> CO+H2O

Can you tell me the equilibrium proportions of these four species as a function of temperature?

What is a good catalyst to speed the forward reaction? Would the same catalyst also speed the reverse reaction, or would a different catalyst work better?

Wait a minute, you are quoting the reaction in the reverse of what most people think of. This reaction is used industrially to produce hydrogen from methane (partial oxidation of methane, followed by the water gas shift). Are you trying to produce CO?

In the formation of hydrogen, one way to separate the hydrogen out is to pass it over a palladium membrane. The hydrogen will pass through the palladium, but the other species will not. Essentially the hydrogen reacts with the palladium to form palladium hydride, diffuses through the metal layer and reforms molecular hydrogen on the other side of the membrane. In this paper they describe the reaction being driven to the H2+CO2 side by removing the hydrogen through such a membrane.

It looks like there are several transition metals that will catalyze this reaction. Even gold. Many people on this forum like gold, perhaps they will find this interesting?
hero member
Activity: 518
Merit: 500
October 11, 2012, 02:28:13 PM
#16
I have a question for you - and guess what, its bitcoin related!! Chemistry, I dont know, but you seem like a bit of a lateral thinker so here goes.

I'd like to manufacture a china mug, that like a casacus (can I even spell that!!) coin has a hidden private key inside it. I imagine that there would be a hollow botom in the mug and the key place in the compartment before it was fired. In this way it really is almost impossible to get at the key without obviously breaking the mug, or x-raying it which I assume is beyond a normal persons methods.

One technique is to "print" the key on to thin tungsten foil - such is available at reasonable cost, and this would not melt at the firing temperature of normal pottery. So you could use a stamp and stamp it on for example, you could do this by hand in theory. But this wont work because the process must be 100% error free - the only way you would find out a mistake had been made is when the mug is smashed and the private key does not work, (and you loose your bitcoins!!) so a better way to do this is needed. In practice, I need a way to photographically do this from a printout of the key from a normal printer. Some sort of UV sensative coating that I could contact print from, possibly develop, and then perhaps as a result of the firing or perhaps not would etch the metal so that it could reliably and certainly be read. Or can I glaze or enamel a tungsten foil photographiclly? What about a platinotype on a tungsten base? Too complex, methinks. (And expensive!!) Its got to be pretty certain to work, or capable of being checked for readability before insertion.

In truth I am dead-ended here and would welcome any further ideas from the OP or someone else. I want a bitcoin piggy bank, that truly has to be smashed to release its contents!! How cool would that be?




Is there a question in there somewhere? Smiley Would the bitcoin address be printed on the outside of the mug? That wouldn't be hard, just use standard printing/glazing techniques, the hard part is ensuring the mug has the correct address/key pair, but using correct inventory management and flow systems should let you match these up. Could you have a robotic engraving system set up to engrave the private key on the metal disk which gets inserted into the clay before firing? It would just be a string of characters, so current engraving programs should be capable.
sr. member
Activity: 286
Merit: 251
October 11, 2012, 01:32:21 PM
#15
I have a question for you - and guess what, its bitcoin related!! Chemistry, I dont know, but you seem like a bit of a lateral thinker so here goes.

I'd like to manufacture a china mug, that like a casacus (can I even spell that!!) coin has a hidden private key inside it. I imagine that there would be a hollow botom in the mug and the key place in the compartment before it was fired. In this way it really is almost impossible to get at the key without obviously breaking the mug, or x-raying it which I assume is beyond a normal persons methods.

One technique is to "print" the key on to thin tungsten foil - such is available at reasonable cost, and this would not melt at the firing temperature of normal pottery. So you could use a stamp and stamp it on for example, you could do this by hand in theory. But this wont work because the process must be 100% error free - the only way you would find out a mistake had been made is when the mug is smashed and the private key does not work, (and you loose your bitcoins!!) so a better way to do this is needed. In practice, I need a way to photographically do this from a printout of the key from a normal printer. Some sort of UV sensative coating that I could contact print from, possibly develop, and then perhaps as a result of the firing or perhaps not would etch the metal so that it could reliably and certainly be read. Or can I glaze or enamel a tungsten foil photographiclly? What about a platinotype on a tungsten base? Too complex, methinks. (And expensive!!) Its got to be pretty certain to work, or capable of being checked for readability before insertion.

In truth I am dead-ended here and would welcome any further ideas from the OP or someone else. I want a bitcoin piggy bank, that truly has to be smashed to release its contents!! How cool would that be?


sr. member
Activity: 440
Merit: 250
October 11, 2012, 01:14:20 PM
#14
As a star collapses, we get heavier and heavier elements being created due to nuclear fusion.

What size of star is required to implode in order to create the element Unobtanium?

;P

Hrm, a nuclear chemistry question, you guys are bringing out the big guns.

Without going in to the extremely complicated math, I did this calculation and I found that the distribution of elements produced would never give a noticable amount of unobtainium. Essentially, before a star can produce unobtanium it becomes a black hole and therefore the unobtanium is unobservable.
I think you have to inject some Nonexistium into the star's core first, but if you don't do it right, then during the implosion a large amount of Urassisgrassium is ejected, so you have to be really careful about it.
hero member
Activity: 518
Merit: 500
October 11, 2012, 11:47:04 AM
#13
As a star collapses, we get heavier and heavier elements being created due to nuclear fusion.

What size of star is required to implode in order to create the element Unobtanium?

;P

Hrm, a nuclear chemistry question, you guys are bringing out the big guns.

Without going in to the extremely complicated math, I did this calculation and I found that the distribution of elements produced would never give a noticable amount of unobtainium. Essentially, before a star can produce unobtanium it becomes a black hole and therefore the unobtanium is unobservable.
hero member
Activity: 518
Merit: 500
October 11, 2012, 11:39:56 AM
#12
How can I distinguish and separate the following 4 molecules which are in equilibrium at high temperature: H2, CO, CO2, H2O.

This is the water gas shift reaction:  H2+CO2 -> CO+H2O

Can you tell me the equilibrium proportions of these four species as a function of temperature?

What is a good catalyst to speed the forward reaction? Would the same catalyst also speed the reverse reaction, or would a different catalyst work better?

I will have to look into this more, I will do some diggin and get back to you in a bit. Off the top of my head, I think the usual catalyst for this reaction is iron, or an iron-copper alloy. Catalysts work by reducing the activaiton energy of a reaction, thus they work for both the forward and backward direction. The proportions of species produced depends on the conditons used (temperature and pressure).
hero member
Activity: 518
Merit: 500
October 11, 2012, 11:33:07 AM
#11
> potassium hydroxide and sodium hydroxide are interchangeable. They are both strong acids and

I think you meant alkalies!

Sorry about that, just slipped. Edited the previous post.
hero member
Activity: 1470
Merit: 509
October 11, 2012, 11:00:48 AM
#10
As a star collapses, we get heavier and heavier elements being created due to nuclear fusion.

What size of star is required to implode in order to create the element Unobtanium?
sr. member
Activity: 440
Merit: 250
October 11, 2012, 10:45:25 AM
#9
How can I distinguish and separate the following 4 molecules which are in equilibrium at high temperature: H2, CO, CO2, H2O.

This is the water gas shift reaction:  H2+CO2 -> CO+H2O

Can you tell me the equilibrium proportions of these four species as a function of temperature?

What is a good catalyst to speed the forward reaction? Would the same catalyst also speed the reverse reaction, or would a different catalyst work better?
sr. member
Activity: 420
Merit: 250
October 11, 2012, 09:58:23 AM
#8
> potassium hydroxide and sodium hydroxide are interchangeable. They are both strong acids and

I think you meant alkalies!

I'm hoping he did... they are most certainly basic rather than acidic
sr. member
Activity: 286
Merit: 251
October 11, 2012, 09:14:37 AM
#7
> potassium hydroxide and sodium hydroxide are interchangeable. They are both strong acids and

I think you meant alkalies!
hero member
Activity: 518
Merit: 500
October 11, 2012, 09:07:24 AM
#6
I've always wondered what would happen if replaced lye with potash... (that is potassium hydroxide)...


In most cases, including this one, potassium hydroxide and sodium hydroxide are interchangeable. They are both strong bases and have similar reactivities. There are some salts which have different solubilities with potassium vs. sodium, but that should not be a problem in this case.

The hydroxide is used to neutralize the acid and produce a free base:

R-NH3+ + MOH --> R-NH2 + H2O + M+

Where M can be either K or Na.
sr. member
Activity: 420
Merit: 250
October 10, 2012, 10:54:48 PM
#5
I've always wondered what would happen if replaced lye with potash... (that is potassium hydroxide)...
hero member
Activity: 518
Merit: 500
October 10, 2012, 08:10:50 PM
#4
How do i reduce ephedrine without complicated equipment or precursors?

I suppose you are referring to the reaction reducing ephedrine to methamphetamine (works for pseudoephedrine too). This is simply the removal of one alcohol moiety from the molecule.

R-OH + I2 + H3PO2 --> R-H

Mix ingredients, heat to boil.

Since the ephedrine contains an amine group, add KOH (lye) and extract with an organic solvent.
legendary
Activity: 1372
Merit: 1008
1davout
October 10, 2012, 05:06:34 PM
#3
How do i reduce ephedrine without complicated equipment or precursors?
member
Activity: 70
Merit: 10
October 10, 2012, 04:39:35 PM
#2
seems legit
hero member
Activity: 518
Merit: 500
October 10, 2012, 02:08:27 PM
#1
Hi everybody,

I don't know if this would interest anybody, but I would be willing to answer any chemistry related questions (and get tips in bitcoin).

Questions can be anything from topics you wonder about or are confused by, just want to know more about, or if you are taking a chemistry class and something is stumping you.

My qualifications: I have a BS and MS in Chemistry from Michigan State University (focus on organic chemistry). I am currently working as a chemistry researcher at the largest US chemical company.

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Tips can be sent to: 1FjVtT9e3StFWkkRS4xgQtRfBrB9TbVo9T
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