Experimental design and multiple response optimization of batch leaching tests of volcanic ashes

Area of Science:

• Environmental Geochemistry
• Analytical Chemistry

Background:

• Volcanic eruptions release ash, impacting the environment through element release during weathering.
• Understanding chemical element input from volcanic ash is crucial for environmental risk assessment.

Purpose of the Study:

• Optimize batch leaching tests for analyzing ion release from volcanic ash.
• Determine optimal conditions for multielemental analysis of ash weathering products.

Main Methods:

• Utilized chemometric multivariate strategies to optimize leaching variables.
• Employed Darringer's desirability function for simultaneous optimization of element concentrations.
• Analyzed 20 elements (Na to Pb) using ICP-MS (inductively coupled plasma-mass spectrometry).

Main Results:

• Identified solid/liquid ratio and stirring speed as the most significant variables affecting leaching.
• Established optimal experimental conditions for volcanic ash leaching.
• Grouped elements based on their leaching behavior and desirability function values.

Conclusions:

• Optimized leaching protocols provide reliable data for assessing environmental impacts of volcanic ash.
• Methodology enables accurate prediction of chemical element release from volcanic materials.
• Further research can refine understanding of ash weathering and element bioavailability.