Aerobic biodegradability under simulated composting environments
Gas Endeavour® can be configured to evaluate aerobic biodegradability of polymer samples using home or industrial compost under a simulated composting environment like any home composting or controlled composting sites. The instrument allows for continuous and on-line monitoring of oxygen demand or depletion caused by aerobic respiration of compost bacteria. This arrangement should be served as a practical analytical tool of biodegradability evaluation under similar conditions of home composting or controlled composting facilities for internal study or research purpose. Microcrystalline cellulose is often used as a positive control for the test validation. In the current study, biodegradability test of microcrystalline cellulose samples is evaluated at two different concentrations under a simulated composting environment at 58oC similar with a controlled composting condition. After the incubation of 100 days, the biodegradability of two cellulose samples is 87 ±8% and 62 ±11% for high and low concentrations, respectively. For the higher concentration cellulose sample, 72% biodegradability is achieved after 45 days. The validity criteria of ISO 14851 are fulfilled, i.e., the positive control reaches 70% after 45 days and the standard deviation of test result is within ±20%.