Opening bottle with sparkling water
Opening bottle with sparkling water¶
Written by Svetlana Kyas (ETH Zurich) on Mar 31th, 2022
This tutorial shows how to simulate the solubility of CO2 in water or, more simply, the effect of the carbon dioxide released when you open the bottle of sparkling water.
Opening bottle with sparkling water, Source: flavorman.com
First, we define the chemical system:
from reaktoro import * db = SupcrtDatabase("supcrtbl") # Create an aqueous phase automatically selecting all species with provided elements aqueousphase = AqueousPhase(speciate("H O C")) aqueousphase.setActivityModel(chain( ActivityModelHKF(), ActivityModelDrummond("CO2"), )) # Create a gaseous phase gaseousphase = GaseousPhase("CO2(g)") gaseousphase.setActivityModel(ActivityModelPengRobinson()) # Create the chemical system system = ChemicalSystem(db, aqueousphase, gaseousphase) # Create the equilibrium solver solver = EquilibriumSolver(system)
Then, we define the range of pressures using the
linspace() function of the numpy library. The initial and final pressures correspond to the values in the bubble bottle before and after opening.
import numpy as np closedP = 3.79 # in bars openP = 1.01325 # in bars pressures = np.linspace(openP, closedP, num=100)
Note: A typical carbonated soft drink contains approximately 3–4 volumes (6–8 g/L) CO2. To obtain the amount of mol of CO2, we need to perform the following calculations: 8 g/L = 8 / 44.01 mol = 0.18 mol, where 44.01 g/mol is the CO2 molar mass.
Next, we go through the created pressure list and collect the CO2(g) amounts obtained in the equilibrated chemical for a given pressure.
import pandas as pd df = pd.DataFrame(columns=["P", "amountCO2"]) for P in pressures: state = ChemicalState(system) state.setTemperature(20.0, "celsius") state.setPressure(P, "bar") state.add("H2O(aq)", 0.5, "kg") # add ~ half a liter of water state.add("CO2(g)", 0.18, "mol") # add calculated amount of gas res = solver.solve(state) df.loc[len(df)] = [P, float(state.speciesAmount("CO2(g)"))]
To visualize the changes in the CO2(g) amount in the bottle, we export bokeh python plotting package.
from bokeh.plotting import figure, show from bokeh.models import HoverTool from bokeh.io import output_notebook output_notebook() hovertool = HoverTool() hovertool.tooltips = [("amount(CO2) in brine", "@amountCO2 mol"), ("P", "@P")] p = figure( title="CO2(G) AMOUNT IN SPARKLING WATER BOTTLE BEFORE AND AFTER OPENING", x_axis_label=r'PRESSURE [BAR]', y_axis_label='AMOUNT OF CO2(G) [MOL]', sizing_mode="scale_width", plot_height=300) p.add_tools(hovertool) p.line("P", "amountCO2", line_width=3, line_cap="round", line_color='indigo', source=df) show(p)
From the generated plot, it can be seen that reducing the pressure in the bottle (opening the bottle) also reduces the amount of CO2 dissolved in the carbonated beverage, which evaporates as CO2 gas.