Process for producing metal oxides

A method for producing a metal oxide powder, the method comprising:

• introducing a stream comprising a vaporous, hydrolysable metal compound into a stream comprising oxygen via a first feed-in point provided in a first pipe piece comprising one or more static mixer elements, or vice versa, to generate a first material stream;
• introducing, at a velocity vB, a stream comprising at least one fuel gas into the first material stream, which has a velocity vA, via a second feed-in point provided in a second pipe piece comprising one or more static mixer elements, to generate a second material stream;
• introducing the second material stream, which leaves the second pipe piece, into a reaction chamber to ignite the second material stream and to convert the second material stream into a flame, to obtain a mixture;
• and
• separating solids from the mixture,
• wherein
• vB, which is at least 50 Nm/s, is greater than vA, which is at least 5 Nm/s, with the proviso that the stream comprising the vaporous, hydrolysable metal compound does not comprise a silicon compound as the sole metal compound;
• a LA/DA ratio is 2-20, where LA is a length of the first pipe piece and DA is an inner diameter of the first pipe piece;
• and
• a LB/DB ratio is 2-20, where LB is a length of the second pipe piece and DB is an inner diameter of the second pipe piece.