Masters thesis titled “Extraction and Analysis of Dissolved Organic Matter (DOM) from Biochar Samples ” was completed as part of the PYRASOL project.
Biochar (BC) has been immensely used in soil and water remediation. Its application depends on its physical, chemical, and BC- derived DOM (BC-DOM) characteristics. DOM is defined as the organic matter portion that passes through 0.45µm filters, a complex heterogeneous mix of organic compounds, comprising polysaccharides, amino acids, proteins, and humic substances, and carboxyl groups. DOM serves as an oxidizing and reducing agent in metal conversion and soil speciation. Further, it is also a source of carbon and energy by microbes inhabited in the soil and aquatic environment for their growth. DOM exists naturally and also derived from different BC. This master thesis investigates the BC-DOM using various extractant solvents such as deionized water (DI), Acid (HCL), and Base (NaOH) and to select the optimum mass of BC and the best extractant solvent among the three extractants after the extraction process. The analysis was carried out using UV-vis Spectroscopy, pH measurements, and TOC- analyzer.
The extraction process was investigated every eight days for 32 days using the Biomacon biochar (BioCR) – was wood and shrub cuttings. The feedstocks were obtained from a farm in Niedersachen. The feedstocks were pyrolyzed up to a temperature of 650 °C pyrolysis unit of Biomacon (PYRASOL project partner) for 60 minutes. The obtained biochar was dried at 105 °C before use and crushed through a 0.25mm sieve. Then it was incubated in DI, HCL, and NaOH solutions; the samples were prepared in triplicate in the ratio of 1g BC to 20ml of the solutions after stirring it for 24 hours in a magnetic stirrer.
Student: Tsegai Asfaha
Supervisors: Rahul Ramesh Nair, Moni Mohan Mondal
Examiners: PD Dr.-ing habil Dirk Weichgrebe, Prof. Regina Nogueria