Gas-pore generating agent for pore-forming in unset concrete and method for its use in the preparation of a cellular concrete mixture

A gas pore former (I) for the prodn. of pores in fresh concrete contains Al powder and ethanolamine ester(s) of synthetic fatty acid(s) of formula H3-pN(CH2CH2OCOR)p (II), where R = 10-16C alkyl and p = 1-3. Also claimed is a process for the prodn of cellular concrete mixts. by adding an aq. suspension contg. 0.1-1.0 g (I)/l water to the mixt. of binder, minerals and mix water. (I) contains Al powder and (II) ina wt.% ratio of (70-94) to (6-30), and the Al consists of a narrow fraction with a particle size of 10-80 microns. The binder and mineral component are premixed with part of the mix water, and the rest of the mix water is added afterwards in the form of an aq. suspension of (I). Pores are formed both by air injection and, after a delay of 2-10 mins., by active gas generation in the mix. The mix can be further processed before gas generation has stopped, but active gas generation has stopped before the mix starts to set.