Reactive distillation is one of the most well-established integrative separation processes in chemical industry which is used for the production of e.g. fuel additives. Recently, the feasibility of enzymes in reactive distillation columns was demonstrated, which possibly extends the scope towards more selective reactions with chiral products. However, the low thermal stability of enzymes necessitates a more frequent catalyst exchange which is usually a knock-out criterion for this process due to very high costs of catalytic structures and long process shut down times. In this work, an in situ production method for biocatalytic coatings on structured packings is presented which enables production and renewal of the catalytic structures in place, i.e. without disassembly of the column internals. By flooding the column with reacting enzyme/silica-sol, gauze structured packings are covered with a uniform layer of gel, which after drying results in a catalytic coating containing immobilized enzymes. The in situ method could help simplify the catalyst exchange in reactive distillation processes and furthermore allows changes in the reactive section in terms of amount and position of the catalyst which are important process parameters in the design phase of reactive distillation processes. (C) 2016 Elsevier B.V. All rights reserved.