Acid catalyst analyzer system comprising: a first flowmeter configured to receive a sample volume that includes an acid catalyst mix and a hydrocarbon fluid, the acid catalyst mix including an acid, water, and acid soluble oils; a separation vessel configured to receive the sample volume from the first flow meter, and to separate the acid catalyst mix from the hydrocarbon gas; a second flowmeter adapted to receive the hydrocarbon fluid that has been separated from the acid catalyst mix, through a first valve; a third flowmeter adapted to receive the acid catalyst mix that has been separated from the hydrocarbon fluid through a second valve; and data processing apparatus operatively coupled to the first flowmeter 108, the second flowmeter, and the third flow meter, the data processing apparatus configured to execute computer software instructions stored on a computer-readable medium to perform operations comprising: receiving a first set of mass flow and density readings, a second set of mass flow and density readings, and a third set of mass flow and density readings from the first flowmeter, the second flowmeter, and the third flowmeter, respectively, determining a concentration of the hydrocarbon fluid in the sample volume, and transmitting a signal to control a level by which the first valve is open to maintain a mass balance between the first flowmeter, and the second and the third flowmeters. a first flowmeter configured to receive a sample volume that includes an acid catalyst mix and a hydrocarbon fluid, the acid catalyst mix including an acid, water, and acid soluble oils; a separation vessel configured to receive the sample volume from the first flow meter, and to separate the acid catalyst mix from the hydrocarbon gas; a second flowmeter adapted to receive the hydrocarbon fluid that has been separated from the acid catalyst mix, through a first valve; a third flowmeter adapted to receive the acid catalyst mix that has been separated from the hydrocarbon fluid through a second valve; and data processing apparatus operatively coupled to the first flowmeter 108, the second flowmeter, and the third flow meter, the data processing apparatus configured to execute computer software instructions stored on a computer-readable medium to perform operations comprising: receiving a first set of mass flow and density readings, a second set of mass flow and density readings, and a third set of mass flow and density readings from the first flowmeter, the second flowmeter, and the third flowmeter, respectively, determining a concentration of the hydrocarbon fluid in the sample volume, and transmitting a signal to control a level by which the first valve is open to maintain a mass balance between the first flowmeter, and the second and the third flowmeters. receiving a first set of mass flow and density readings, a second set of mass flow and density readings, and a third set of mass flow and density readings from the first flowmeter, the second flowmeter, and the third flowmeter, respectively, determining a concentration of the hydrocarbon fluid in the sample volume, and transmitting a signal to control a level by which the first valve is open to maintain a mass balance between the first flowmeter, and the second and the third flowmeters.