Of the adsorption of gases. Section II. Kinetics and energetics of gas adsorption. Introductory paper to section II.
Of the adsorption of gases. Section II. Kinetics and energetics of gas adsorption. Introductory paper to section II.
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DOI：
10.1039/tf9322800195
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发表时间：
1932-01-01
影响因子：
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通讯作者：
Freundlich, H
中科院分区：
文献类型：
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作者：
Freundlich, H
当我收到法拉第学会的盛情邀请，请我为气体吸附的动力学和能量学一节写一篇介绍性论文时，”我很怀疑自己是否真的能够接受邀请，因为我已经多年没有在这个课题上进行任何实验室工作了，因此我不能提出任何新的东西。然而，对于那些不太熟悉这个主题的人来说，一个非常普遍的调查有时是很受欢迎的。如果我不得不说的话似乎有些无趣，我希望那些将气体吸附作为工作主题的人会原谅我。那些首先研究气体吸附的人，如德·索绪尔（de Saussure）、儒林（Joulin）和其他人，很快就注意到他们必须处理真正的平衡：在给定的压力下，平衡吸附的量是相同的，无论他们是在上升还是下降的压力下测量。因此，可以毫不犹豫地使用热力学的观点。人们也很早就注意到，在纯气体中，平衡是很快达到的，一般在几秒钟或几分钟内。我们没有发现化学反应的速度变化范围如此之宽，至少在正常的吸附情况下没有发现。在一个含有固体和气体的两相系统中，压力发生严格可逆的变化，而且很快就达到了平衡，这一事实常常被用来作为一个标准，来假定我们实际上是在研究吸附的情况，也就是说，研究主要受表面力支配的现象。我们不能否认，这些标准并不十分令人满意。例如，这种吸附很难与高度多孔物质的化学平衡相区分，例如沸石或permutite，其中几乎每个分子都位于自由的内表面上。然而，我们知道有些情况下，像氩这样的化学惰性物质会被吸附，而像云母这样的平面也能被吸附。这些情况与化学活性气体吸附在多孔物质表面上的情况非常相似，因此吸附作为一种表面现象的存在已被普遍接受。如果我们有一个在表面上的平衡特性，并且这个特性随吸附的气体量而变化，那么我们就可以把它依赖于压力p的方式与每单位表面的吸附量zc联系起来。的表面张力
When I received the kind invitation of the Faraday Society to give an introductory paper for the section Kinetics and Energetics of Gas Adsorption,” I w7as very doubtful whether I really was able to accept it. For I have not carried out any laboratory work on this subject for many years, and I am not therefore in a position to bring forward anything new. A very general survey is, however, sometimes quite welcome to those who are not so familiar with the subject. I hope that those to whom gas adsorption is a main theme of work will pardon me if what I have to say may seem somewhat uninteresting. Those who first investigated gas adsorption, de Saussure, Joulin and others, noticed soon that they had to deal with true equilibrium: the amount adsorbed in equilibrium with a given pressure was the same, whether they measured with rising or falling pressures. Thermodynamic points of view may therefore be used without hesitation. It was also very early noticed that the equilibrium in pure gases is reached very quickly, generally in the course of seconds or minutes. We do not find that wide range of velocities so characteristic of chemical reactions, at least not under normal circumstances of adsorption. The fact that we have strictly reversible changes of pressure in a two-phase system containing a solid and a gas, and that these equilibria are reached quickly, is often used as a criterion of the supposition that we are really dealing with cases of adsorption, that is to say with phenomena mainly ruled by surface forces. We cannot deny that these criteria are not quite satisfactory. Such an adsorption is, for instance, hard to distinguish from the chemical equilibrium of a highly porous substance, such as a zeolite or permutite, in which practically every molecule lies on a free internal surface. We know, however, of cases where substances, chemically so inert as argon, are adsorbed and where plane surfaces, like those of mica, are able to adsorb. The similarity of these cases with those in which chemically active gases are adsorbed on the surfaces of porous substances is so great that the existence of adsorption as a surface phenomenon is very generally accepted. If we had a property characteristic of the equilibrium on the surface and changeable with the amount of gas adsorbed, we might correlate thermodynamically the way in which it depends on the pressure p with the amount adsorbed per unit of surface zc. The surface tension of the