A portable low cost coulometric micro-titrator for the determination of alkalinity in lake and sediment porewaters

作者：Stein**erger Thomas; Kathriner Patrick; Meier Philipp; Mistretta Alexander; Hauser Peter C; Mueller Beat

来源：Sensors and Actuators B: Chemical , 2018, 255: 3558-3563.

DOI：10.1016/j.snb.2017.09.191

• Alkalinity
• Micro-titrator
• Porewater
• Lakes
• Sediment

Alkalinity is an important parameter in oceans, lakes, groundwaters and sediment porewaters as a link to the global carbon cycle. It is determined by classic titration with acid where sufficient sample volume is available. However, application to the limited amounts of sediment porewater requires a different approach. A portable low cost coulometric micro-titrator based on a RuO2 pH-sensitive electrode and a Ag/AgCl reference electrode requiring 50 pi of total sample volume is presented. By using a distinct sandwich cell design, a well-defined titration volume could be achieved. The micro-titrator performed well within the targeted range of 1-10 mmol (L-1) and a reproducibility within 3.5%. It was successfully applied to lake water and sediment porewater alkalinity measurements of Lake Lucerne and bears the potential for automation and in-situ applications.

• 出版日期2018-2