The invention provides a reactor comprising a reaction chamber having a catalytic surface in contact with reactants in said chamber; and a source for passing electrical current through said catalytic surface. The reactor can be used for dehydrohalogentation reactions, such as dehydrochlorination of HCFC-244bb to HFO-1234yf, and for reactions where zero valent metals are employed for catalysis. The invention further provides a process to prepare HFO-1234yf from HCFC-244bb using an electrically heated reaction chamber.