Organic waste disposal in landfills has created various environmental issues, such as greenhouse gas emissions and leachate. Awareness of this issue has resulted in diverting landfill to compost. Thus, there is a need to develop an analytical tool to select the best composting technology. Therefore, this paper reviews a range of assessment steps designed to evaluate specific sustainability criteria (environmental, social, economic, and technical) for organic waste management to select the most suitable composting technology. Due to the complexity of conflicting criteria and alternatives in composting technology, a multi-criteria decision-making (MCDM) technique is suggested to ensure the quality of the decision-making process. As an additional benefit, the synthesis results via the MCDM tool will be more credible when seeking validation by stakeholders.

SummaryThe effect of microwaves on the functionalization of single-walled carbon nanotubes (SWNTs) by the diazonium method was studied. The usage of a new approach led to the identification of the strength of the interaction (physical or chemical) between the functional groups and the carbon nanotube surface. Moreover, the nature (chemical formula) of the adsorbed/grafted functional groups was determined. According to thermogravimetric analysis coupled with mass spectrometry and Raman spectroscopy, the optimal functionalization level was reached after 5 min of reaction. Prolonged reaction times can lead to undesired reactions such as defunctionalization, solvent addition and polymerization of the grafted functions. The strength (chemi- vs physisorption) of the bonds between the grafted functional groups and the SWNTs is discussed showing the occurrence of physical adsorption as a consequence of defunctionalization after 15 min of reaction under microwaves. Several chemical mechanisms of grafting could be identified, and it was possible to distinguish conditions leading to the desired chemical grafting from those leading to undesired reactions such as physisorption and polymerization.

Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) is based on decision model to measure alternative with shortest distance to positive ideal solution and the farthest distance from negative ideal solution. With growing complexity in decision making, vagueness and uncertainty often exist in human judgement. To manage conflicting criteria, a hierarchy structure in TOPSIS is proposed where the main criteria, sub-criteria, and alternatives are arranged in multi-level. To rate each alternatives, the weight of each criterion is evaluated using linguistic value before converted into fuzzy number as a way to measure the experts opinion. In this paper, we demonstrates our general framework for the development of hierarchal fuzzy TOPSIS. We also highlighted our initial finding on the criteria and alternatives in our case study i.e. selection of decomposition technology for food waste management. It is anticipates our work will contributes better decision making in the related area.