Refine
Document Type
- Conference Publication (1)
- conferencepaper (1)
- Contribution to a Periodical (1)
- Other (1)
Has Fulltext
- no (4)
Is part of the Bibliography
- no (4)
Keywords
- Extrusion (2)
- Bernsteinsäure (1)
- Biopolymer (1)
- Compounding (1)
- Granulate (1)
- Levulinic Acid (1)
- Microwave (1)
- Plastic feeding (1)
- Pressure (1)
- Reactive Extrusion (1)
One major problem of a continuous process like plastic extrusion is their incapability to deal with non-local gas pressure. This is an inherent problem because a continuous process has an open end in the feeding port where pressure can escape. In this study a novel feeding system was developed to enable granulate feeding into gas pressurized processes inside a single- or twin-screw extruder. With this apparatus gas pressure can be applied inside the extrusion process. The apparatus separates the pressurized extruder from the dosing equipment that feeds the extruder. It keeps the pressure inside the system while continuously feeding new material into the process. A small-scale prototype was designed for proof-of concept. The small size of the prototype was able to handle small amounts of granulates of around 100 - 200 g/h. An applied gas pressure of 8 bar was achieved. In future optimizations, throughput can be increased and maximum applied gas pressure towards 15-20 bar.
The increasing prevalence of bio-based and biodegradable plastics as an alternative to traditional plastics derived from crude oil is a noteworthy trend. Polybutylene succinate (PBS), a plastic produced from succinic acid, is among the promising materials for the future. However, the production of bio-based succinic acid through biotechnical processes in controlled environments presents challenges. This process leads to increased costs and is currently not economically competitive compared to crude oil-based succinic acid production. In addition to succinic acid, levulinic acid is another monomer produced in the same process.
A novel approach to the digestion of biomass has been developed to address the issue of biotechnological production of bio-based platform chemicals. This innovative process employs microwave radiation, pressure, and temperature to convert wood residues into succinic acid and levulinic acid. Various catalyst concentrations and biomass ratios were tested in a batch process, with high-pressure liquid chromatography (HPLC) and liquid chromatography–mass spectrometry (LC/MS) analyses revealing the formation of succinic acid, levulinic acid, formic acid, and 2 oxoglutaric acid. The results demonstrate that microwaves combined with a metal salt catalyst can be used to produce platform chemicals from lignocellulosic biomass.
To further advance the continuous production of PBS, a twin-screw extruder was modified and adapted after the successful results obtained from the batch processes. This setup enables additional experiments to evaluate the transferability of batch process results to continuous reactions, facilitating the scale-up and economic viability of the overall PBS production process in the future.
