Question

Adsorption of wine proteins is an essential step in the production of white and rosé wines. We have measured the adsorption kinetics by immersing a cation exchange resin (Macro-Prep 50S, dia. = 200 µm, Bio-Rad Laboratories) in wine at controlled temperature (20 °C). Protein content of the solution was measured over time. Protein adsorption followed the Langmuir isotherm: q₀ = 184 mg/g, and K = 8.09 mg/L. The following data were obtained when the amount of adsorbent added was 2.329 g/L and the initial concentration was 524 mg/L. Calculate the resin loading vs. time.

Time (min)	Protein Concentration (mg/L)
0	524
5	491
10	405
15	375
20	348
30	313
40	246
50	217
60	181
70	157

Answer 1