(a) A gas-solid catalytic reaction at a high pressure and high temperature is to be undertaken. The catalyst has a relatively low lifetime, meaning it requires to be changed often. Considering this, answer the following:\ \ (i) List four additional operational parameters required to better understand the reaction requirements.\ (2 marks)\ \ (ii) Suggest a suitable reactor design for the above reaction, justify your selection, and indicate any additional information needed before making a final selection.\ (5 marks)\