An apparatus comprising: a vessel component comprising a flow-through interior chamber having an interior sidewall and an exterior sidewall; at least two inlets for introducing chemical components into the flow-through interior chamber; at least one outlet for removing product from the flow-through interior chamber; and an off center rotation component which is operatively connected to the vessel component. During operation of the apparatus, the off center rotation component generates vortical movement of at least two chemical components through the flow-through interior chamber of the vessel, and converts at least a portion of the at least two chemical components to at least one reaction product or product mixture. A method of using the apparatus to produce reaction products or product mixtures. The apparatus and method are useful for producing specialty chemicals such as fragrance and flavor compounds, insect pheromones, petrochemicals, pharmaceutical compounds, agrichemical compounds, and the like.