His mother raised the children by regimen, described by Henry Louis: "I was accustomed to a very strict discipline: it was necessary to wake up on time, to prepare for your duties and lessons, to eat everything on your plate, etc.

Le Chatelier married Geneviève Nicolas, a friend of the family and sister of four fellow students of the Polytechnique.

They had seven children, four girls and three boys, five of whom entered scientific fields; two died preceding Le Chatelier's death.

On the advice of a paper of Le Chatelier that the combustion of a mixture of oxygen and acetylene in equal parts rendered a flame of more than 3000 celsius,[4] in 1899 Charles Picard (1872-1957) started to investigate this phenomenon but failed because of soot deposits.

[5] In 1902 Fouché invented a gas welder tool with French patent number 325,403 and in 1910 Picard developed the needle valve.

[6] Le Chatelier in 1901 attempted the direct combination of the two gases nitrogen and hydrogen at a pressure of 200 atm and 600 °C in the presence of metallic iron.

An air compressor forced the mixture of gases into a steel Berthelot bomb, where a platinum spiral heated them and the reduced iron catalyst.

And thus it was left for Fritz Haber to succeed where several noted French chemists, including Thenard, Sainte Claire Deville and even Berthelot had failed.

In 1901, the critic Henri Cazalis (alias Jean Lahor), listed the workshop as one of the best producers in France of Art Nouveau ceramics.

[9] Henry Louis seems to have encouraged Alfred's workshop and assisted with experiments in the composition of porcelain and the reactions of quartz inclusions, and also designed a thermoelectric pyrometer to measure temperature in the kilns.

In the first issue of La revue de métallurgie, Le Chatelier published an article describing his convictions on the subject,[11] discussing the scientific management theory of Frederick Winslow Taylor.

In 1934, he published an opinion on the French forty-hour work week law in the Brussels publication Revue économique internationale.