"In 2000, a simple, foundational thermodynamic paradox was proposed: a sealed blackbody cavity contains a diatomic gas and a radiometer whose apposing vane surfaces dissociate and recombine the gas to different degrees (A_2 ⇌ 2A). As a result of
differing desorption rates for A and A_2 , there arise between the vane faces permanent pressure and temperature differences, either of which can be harnessed to perform work, in apparent conflict with the second law of thermodynamics. Here we report on
the first experimental realization of this paradox, involving the dissociation of low-pressure hydrogen gas on high-temperature refractory metals (tungsten and rhenium) under blackbody cavity conditions. The results, corroborated by other laboratory
studies and supported by theory, confirm the paradoxical temperature difference and point to physics beyond the traditional understanding of the second law." https://link.springer.com/article/10.1007/s10701-014-9781-5

"A simple device is introduced that utilizes the phenomenon of epicatalysis to establish a stationary temperature difference by which ambient environmental thermal energy might be converted into useful work. [...] Traditional catalysis is a central pivot
around which much of the industrial and biological worlds turn. Positive catalysts satisfy three general principles. First, they increase reaction rates by providing lower activation energies for rate-limiting steps. Second, they are not consumed by
their net reactions although they are intimately involved in them. Third, they do not alter final thermodynamic equilibria of their reactions. Epicatalysts bend this third principle in that they shift the final gas-phase equilibria of reactions." D. P.
Sheehan, T. M. Welsh, Epicatalytic thermal diode: Harvesting ambient thermal energy, Sustainable Energy Technologies and Assessments, Volume 31, February 2019, Pages 355-368 https://www.sciencedirect.com/science/article/pii/S2213138818301838

There is no separate group of "epicatalysts" - actually all catalysts shift the equilibrium and so violate the second law of thermodynamics (even though in most cases the effect is difficult to detect). Here is a catalyst that speeds up the forward
reaction, 2H+ → H_2, but SUPPRESSES the reverse reaction, H_2 → 2H+ (violation of the second law of thermodynamics par excellence):

Yu Hang Li et al. Unidirectional suppression of hydrogen oxidation on oxidized platinum clusters https://www.nature.com/articles/ncomms3500

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An obviously absurd consequence of the second law of thermodynamics is that a catalyst speeds up the forward and reverse reactions equally (by exactly the same factor). In other words, the catalyst cannot shift the position of equilibrium:

"In the presence of a catalyst, BOTH THE FORWARD AND REVERSE REACTION RATES WILL SPEED UP EQUALLY, thereby allowing the system to reach equilibrium faster. However, it is very important to keep in mind that the addition of a catalyst has no effect
whatsoever on the final equilibrium position of the reaction. It simply gets it there faster. [...] If the addition of catalysts could possibly alter the equilibrium state of the reaction, this would violate the second rule of thermodynamics..." https://
courses.lumenlearning.com/introchem/chapter/the-effect-of-a-catalyst/

Scientists should have noticed the obvious absurdity of this particular consequence of the second law of thermodynamics long ago, and applied reductio ad absurdum: Since the consequence is absurd, the underlying premise, the second law of thermodynamics,
is false.

Consider the dissociation-association reaction

A ⇌ B + C

which is in equilibrium. We add a catalyst and it starts splitting A - the rate constant of the forward (dissociation) reaction increases by a factor of, say, 745492. If the second law of thermodynamics is obeyed, the catalyst must increase the rate
constant of the reverse (association) reaction by exactly the same factor, 745492. But this is insane! The reverse reaction is entirely different from the forward one - B and C must first get together, via diffusion, and only then can the catalyst join
them to form A. Catalysts don't speed up diffusion!

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"The second law of thermodynamics describes why a catalyst does not change the chemical equilibrium of a reaction. Suppose there was such a catalyst that shifted an equilibrium. Introducing the catalyst to the system would result in a reaction to move to
the new equilibrium, producing energy. Production of energy is a necessary result since reactions are spontaneous only if Gibbs free energy is produced, and if there is no energy barrier, there is no need for a catalyst. Then, removing the catalyst would
also result in reaction, producing energy; i.e. the addition and its reverse process, removal, would both produce energy. Thus, a catalyst that could change the equilibrium would be a perpetual motion machine, a contradiction to the laws of
thermodynamics." https://en.wikipedia.org/wiki/Catalysis

The above text is extremely silly and confusing, but it can be improved in this way:

The second law of thermodynamics describes why a catalyst does not change the chemical equilibrium of a reaction. Suppose there was such a catalyst that shifted an equilibrium. Introducing the catalyst to the system would result in a reaction to move to
the new equilibrium, producing energy that can be harnessed to do mechanical work. Then, removing the catalyst would result in the reaction to return to the old equilibrium, the lost (converted into work) energy being restored endothermically. Thus, a
catalyst that could change the equilibrium would be a perpetual motion machine of the second kind, a contradiction to the second law of thermodynamics.

Since catalysts CAN change the equilibrium of chemical reactions, the following pompous claim is correct:

Potentially, any catalyst is a perpetual motion machine of the second kind.

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