ANALYSIS OF ENVIRONMENTAL CONTAMINANTS: SOLUTIONS AND METHODOLOGIES

Elemental analyzers are versatile instruments used for a wide range of environmental analyses, including Total Nitrogen, Total Carbon, Total Organic Carbon, Hydrogen, and Sulfur analysis. They employ high-temperature combustion in the presence of oxygen to determine a sample's elemental composition and key indicators of soil quality, environmental contamination, and ecosystem health.

Some of the most pressing environmental challenges include:


1. Pollution Monitoring and Environmental Remediation: elemental analysis reveals the extent of pollution at contaminated sites, guiding effective cleanup efforts, tracking remediation success, and adjusting strategies as needed;
2. Ecological Studies: this analysis helps examine the movement of essential elements like carbon and nitrogen, ensuring ecosystem health and evaluating the overall health of ecosystems;
3. Climate Change Research: elemental analysis enables the quantification of carbon storage in soils and vegetation, which is vital for climate change mitigation;
4. Regulatory Compliance: this method assists in monitoring adherence to environmental regulations.

The variability of environmental samples, the necessity of detecting low concentrations, and the complexity of sample preparation and instrument calibration can make these analyses quite challenging. To meet these needs, laboratories require specialized solutions and technologies.

Determining Total Organic Carbon (TOC) can be one of the most challenging tasks, primarily due to the necessary preliminary acidification to remove any inorganic traces, and the technology involved.

Many solutions on the market do not utilize advanced technologies that can protect them from acidic vapors generated by the combustion of an acidified sample. This leads to increased consumable usage and frequent instrument maintenance.

The solvent extraction technique enables environmental laboratories to efficiently isolate target analytes from various matrices, including oils and grease from wastewater, and hydrocarbons like dioxins and PCBs from soil and sediments, for quantitative or further qualitative analysis.

This process involves the selective transfer of compounds from one phase (e.g., solid or liquid) to another based on their solubility in a specific solvent.

For instance, assessing the concentration of oil and grease in wastewater is essential for designing and operating wastewater treatment plants. Further, monitoring oil and grease in surface water as a pollution indicator is important for determining the impact on water quality and implementing corrective measures.

➔ Why choose the Randall method for your solvent extractions instead of the Soxhlet one? 

Several solvent extraction techniques exist, with Soxhlet extraction being the most well-known. Soxhlet is a simple technique popular for its application range, repeatability, and reliability. Advances in extraction technology have led to enhanced techniques like Randall extraction, also known as hot solvent extraction. This technique maintains the benefits of Soxhlet extraction, including compliance with official methods from organizations such as AOAC, UNI, EPA, and ASTM, while introducing several key advantages.

Randall extraction immerses the sample directly in boiling solvent, improving solvent recovery, analyte solubility, and extraction efficiency. The faster extraction process also reduces the risk of thermal degradation associated with prolonged heating in Soxhlet extraction.

Automated solvent extractors take these improvements a step further. Automated controls ensure consistent and precise extraction conditions, minimizing variability and enhancing reproducibility. Additionally, automation reduces direct contact with hazardous solvents, creating a safer working environment.

The SER 158 automatic solvent extractor transforms the extraction process by employing the Randall extraction method, delivering precise and consistent results that are up to five times faster than the traditional Soxhlet method. In contrast to the labor-intensive Soxhlet technique, the SER 158 maximizes efficiency by requiring only two minutes of operator involvement. 

Moreover, it is a highly versatile solution, capable of accommodating various sample sizes and types while handling different solvents, making it suitable for a wide range of applications.

This innovative solvent extractor addresses the limitations of traditional methods, eliminating risks such as operator exposure to solvents and the possibility of sample burning. The advanced SolventXpress™ technology facilitates smart solvent dispensing, ensuring minimal exposure to solvents and prioritizing operator safety. The SafeEnd™ feature automatically raises the cups after the final extraction step to prevent the extracted material from burning.
The design also prioritizes solvent recovery. The titanium condenser recovers over 90%, which is then collected in a cooled recovery tank. Depending on the type of sample you analyze, which must not have contaminated the solvent, it is possible to reuse the solvent for further analysis.