Terephthalic acid from renewable sources: early-stage sustainability analysis of a bio-PET precursor

The present work was performed because of the paramount importance of terephthalic acid (PTA) in the current chemical industry. It represents the missing element for the production of 100% bio-PET (polyethylene terephthalate) and has a market with continuous growth. The other monomer, monoethylene glycol (MEG), is already widely available from renewable sources. Considering the wide relevance, not only scientific but also social, covered by the possibility of producing one of the most frequently used polymers from renewable sources, this analysis is aimed at the environmental assessment of alternative routes for the production of PTA. In order to do this, the life cycle assessment (LCA) methodology was adopted as a scientific tool which is able to estimate the environmental performance of three pathways from different renewable sources, comparing the results with the traditional technology. An early stage approach was used by comparing different scenarios with two independent methods: CED (cumulative energy demand) and ReCiPe. The results prove that the bio-routes to PTA could be very competitive, in particular, if organic waste streams are converted into raw materials for the production of building blocks. On the other hand, the adoption of dedicated crops has some limitations and it seems not to be the right solution to mitigate climate change by reducing fossil sources

Comparison of desalination technologies using renewable energy sources with life cycle, pestle, and multi-criteria decision analyses

Nowadays, desalination continues to expand globally, which is one of the most effective solutions to solve the problem of the global drinking water shortage. However, desalination is not a fail-safe process and has many environmental and human health consequences. This paper investigated the desalination procedure of seawater with different technologies, namely, multi-stage flash distillation (MSF), multi-effect distillation (MED), and reverse osmosis (RO), and with various energy sources (fossil energy, solar energy, wind energy, nuclear energy). The aim was to examine the different desalination technologies’ effectiveness with energy sources using three assessment methods, which were examined separately. The life cycle assessment (LCA), PESTLE, and multi-criteria decision analysis (MCDA) methods were used to evaluate each procedure. LCA was based on the following impact analysis and evaluation methods: ReCiPe 2016, IMPACT 2002+, and IPCC 2013 GWP 100a; PESTLE risk analysis evaluated the long-lasting impact on processes and technologies with political, economic, social, technological, legal, and environmental factors. Additionally, MCDA was based on the Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) method to evaluate desalination technologies. This study considered the operational phase of a plant, which includes the necessary energy and chemical needs, which is called “gate-to-gate” analysis. Saudi Arabia data were used for the analysis, with the base unit of 1 m3 of the water product. As the result of this study, RO combined with renewable energy provided outstanding benefits in terms of human health, ecosystem quality, and resources, as well as the climate change and emissions of GHGs categories

Integrated Biorefineries for Algal Biomolecules

Algae are a renewable source of biomolecules for multiple applications ranging from fuels to specialties. However, their implementation as feedstock in industrial processes has only been achieved for few high-value products. This is due to the elevated costs in cultivation and downstream processing. In order to decrease the biorefinery costs and to enhance the overall process profitability, new separation processes need to be developed. Such processes must start from the understanding of the cell architecture, as a basis to develop an optimal fractionation strategy, and must include selective and mild disentanglement processes, in order to preserve the functionality of the target molecules. In this regard, we propose novel integration concepts such as self-disintegration, simultaneous disintegration and disentanglement, and self-separating systems within the framework of process intensification, in such a way that auxiliary chemicals, solvents and numerous unit operations become redundant