Electronic waste, sustainability

Already at an early stage of the research in the semiconductor dispersions, attempts have been made to carry out water splitting, CO2 reduction, etc., in other words, the same photoelectrochemical processes as in the macroscopic PEC cells. The results obtained are summarized in [51-55]. We shall confine ourselves, however, to the processes that might underly some methods of purification, eg., of waste waters etc. These processes are stimulated by electrons and holes produced in the particles by light. As only one type of the current carriers is consumed in the "useful" reaction, measures should be taken to remove the other type from the particle in order to preserve its electroneutrality and sustain the process. For this purpose a sacrificial electron donor (or acceptor) is to be introduced into the electrolyte solution. Often it is the solvent that plays sacrifice. Some examples are listed below. 

Presently there is a huge potential market for recyclable, energy efficient, and more environmentally friendly composite materials. The utilization of natural fiber can thus lead to the reduction of waste disposal problems and environmental pollution. These NFC find applications in various engineering, electronic and automotive fields once the issues such as moisture sensitivity, compatibility, dispersion are addressed in a proper way. Green, environmentally friendly, sustainable, renewable, biodegradable, composites from natural fibers are most desired materials for future. 

Because there is currently no strategy in place for the identification or safe disposal of treated furniture, in-use and discarded furniture and electronics will continue to be a source of indoor and outdoor exposure. More research is urgently needed to develop and refine sustainable end-of-life solutions, especially for e-waste. 

Transition metal catalysis is a major driving force for development of new approaches in organic synthesis, medicinal chemistry, preparation of biologically active and pharmaceutical molecules, as well as in numerous applications related to material science and molecular electronics. Recent advances in green and sustainable chemistry emphasized the key role of waste-free chemicals production. Especially critical in fine chemicals synthesis is that high values of E-factor are not uncommon. Increasing demand in very complex molecular structures enforces implementation of sophisticated multistep synthetic procedures and further complicates the waste/product balance. On the other hand, so far most of the commodity chemicals remain to be produced by classical procedures, which are not green. 

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