Contents of the textbook

Contents

1

Properties of carbon dioxide

1.1 General data 1.2 Molecular structure 1.3 Radiation absorption

2

The importance of carbon dioxide

2.1 Carbon dioxide as the basis of life 2.2 CO 2 as a greenhouse gas 2.3 The carbon footprint 2.4 The carbon balance of the earth

3

Carbon dioxide content of air

3.1 Carbon dioxide in the atmosphere 3.1.1 Historical development of the CO 2 content of the atmosphere 3.1.2 The inorganic carbon cycle 3.1.3 The organic carbon cycle 3.1.4 Measurements of the CO 2 content of the atmosphere 3.1.5 Current situation 3.2 Carbon dioxide in the soil air

4

The carbonic acid system in water

4.1 Solution of gaseous CO 2 in water 4.2 CO 2 and the pH value of natural waters 4.3 Chemical reaction with water - the carbonic acid forms 4.4 The simplified carbonic acid system 4.5 The Equilibrium constants 4.5.1 Formation of carbonic acid (hydration) 4.5.2 The dissociation constants of carbonic acid 4.5.3 Proportions of carbonic acid forms 4.6 Buffering 4.7 Solution of lime in water 4.7.1 Preliminary note on lime 4.7.2 Lime solution

5

The importance of CO

2

in the water cycle

5.1 Weathering 5.2 Rainwater 5.3 Leachate 5.4 Groundwater 5.5 Spring water 5.6 Running waters 5.7 Lakes 5.7.1 Carbon cycle in standing water 5.8 World Oceans 5.9 Raw water for drinking water treatment 5.10 Cold water geysers 5.11 Hardly soluble carbonates

6

Thought model for carbonic acid in water

6.1 Open system 6.2 Closed system

7

Basics for calculations

7.1 Calculation of the constants in the carbonic acid system 7.1.1 Solubility constants for CO 2 7.1.2 The equilibrium constants in the base system 7.2 Analytical detection of carbonic acid forms 7.2.1 TIC and DIC 7.2.2 Determination of acid and base capacity 7.2.3 m-value and p-value 7.2.4 Equivalence factor  7.3 Calculation of the buffering intensity 7.4 The importance of temperature 7.5 Consideration of ionic strength and activity 7.6 Complexation reactions 7.7 Consideration of the m-value with complex formation 7.8 Summary of the required analysis data

8

Evaluation variables for the carbonic acid system

8.1 Saturation pH value after adjustment with calcite (pH C ) 8.2 Saturation pH value after carbon dioxide exchange (pHA) 8.3 Saturation pH value according to STROHECKER/LANGELIER (pH L ) 8.4 Delta pH value (ΔpH) 8.4.1 Measurement of the ΔpH value 8.5 Saturation index SI 8.6 Calcite dissolving capacity and calcite separation capacity

9

Water treatment

9.1 Deacidification in drinking water treatment 9.1.1 Legal regulations 9.1.2 Basics of deacidification 9.1.3 Physical deacidification 9.1.4 Chemical deacidification 9.1.5 Examples of process variants 9.1.6 Chemical reactions in the deacidification processes 9.1.7 Final pH values of different deacidification methods 9.2 Decarbonization / Softening 9.2.1 Delimitation of terms 9.2.2 Precipitation process 9.2.3 Ion exchange process 9.2.4 Membrane process 9.2.5 Effects of the procedures

10

Sample calculations

10.1 Carbon content of the atmosphere 10.2 CO 2 concentration in the air 10.3 Solubility of CO 2 in water 10.4 Solution of CO 2 in leachate 10.5 pH value of a CO 2 solution 10.6 Supplementary consideration of the lime-carbonic acid system 10.7 Calculation of the carbonic acid content 10.7.1 Calculation of carbonic acid contents with complex formation 10.8 Thought model for carbonic acid in water: Open system 10.9 Calculation of the carbonic acid shapes from the TIC 10.10Acid capacity of pure water 10.11 Saturation index

11

Chemical Basics in Brief

11.1 Basic terms and concentration information 11.2 Ionic strength and activity 11.3 The law of mass action 11.4 pH value 11.5 Acids 11.6 Buffering 11.7 The solubility product

12

Tables

12.1 Values for the HENRY constant 12.2 Base constants as a function of temperature 12.3 Proportions of carbonic acid forms as a function of pH value 12.4 Constants of the complexation of calcium 12.5 Constants of the complexation of magnesium

13

Formula symbols and abbreviations

14

Bibliography

15

Keyword index