Can Non-Recyclable Plastic Waste Be Made Environmentally Sustainable?

After death the fraction of living matter which is not biodegraded (shells, bones, corals, carbonaceous deposits) becomes environmentally sustainable. This is not the case for plastics so that these wastes should be either recycled or made environmentally inert and stored in secure repositories as a resource for future generations. Chemistry has offered different solutions to this problem, and each brings about advantages and disadvantages when compared to other options. One further possible route could consist in the enrichment of the plastics waste in carbon content (“carbonization”), in analogy with the production of charcoal from wood, but we hope to stimulate a debate about all the other possible routes among scientists and engineers in the involved fields.

Characterization of Carbonaceous Deposits on an End-of-Life Engines for Effective Cleaning for Remanufacturing

Remanufacturing is one of the most effective strategies to achieve sustainable manufacturing and restore the performance of end-of-life products. However, the lack of an effective cleaning method to clean carbonaceous deposits severely hampers the remanufacturing of end-of-life engines. To explore an appropriate cleaning method, it is necessary to first study the characterization of the carbonaceous deposits. A broad range of analyses including X-ray fluorescence spectrometry, thermogravimetric analysis, 1H-nuclear magnetic resonance study, X-ray diffraction analysis, and scanning electron microscopy were performed to conduct an in-depth characterization of the carbonaceous deposits. The results showed that a hybrid structure composed of organics and inorganics is the most distinguishing feature of the carbonaceous deposit in end-of-life engines. The inorganics form the skeleton on which organics get attached, thereby resulting in a strong adhesion of the deposit and increasing the difficulty of cleaning. Therefore, a method in which several cleaning forces can be simultaneously applied is more suitable for the present purpose. Molten salt cleaning was chosen to verify the feasibility of this proposal. This method was shown to have the potential to effectively clean the carbonaceous deposit. This finding could contribute towards promoting the effective remanufacturing of end-of-life engines.

GEOLOGY OF CARBONACEOUS DEPOSITS OF THE BIRGILDA STRATA (EAST URAL TROUGH)

The article describes the geological structure of the Birgilda strata, which is widely developed in the East Ural trough. It is shown that the Birgilda black shales, which contain Corg in the range of 0.5–2.7% (average 1.3%), are of the low-carbon type. The exothermic effect in them occurred mainly in the temperature range 570–660 ° С, which corresponds to the greenschist facies of regional metamorphism. On the A-S-C diagram, the rocks of the Birgilda strata are approximately equally scattered over the carbonate-carbonaceous and siliceous-carbonaceous fields and noticeably less in the terrigenous-carbonaceous fields. The Birgilda sequence is characterized by a collisional environment of accumulation and products of destruction of mainly basic igneous rocks.