Steam cracking for the production of light olefins, such as ethylene and propylene, is the single most energyconsuming process in the chemical industry. This paper reviews conventional steam cracking and innovative olefin technologies in terms of energy efficiency. It is found that the pyrolysis section of a naphtha steam cracker alone consumes approximately 65% of the total process energy and approximately 75% of the total exergy loss. A family portrait of olefin technologies by feedstocks is drawn to search for alternatives. An overview of state-of-the-art naphtha cracking technologies shows that approximately 20% savings on the current average process energy use are possible. Advanced naphtha cracking technologies in the pyrolysis section, such as advanced coil and furnace materials, could together lead to up to approximately 20% savings on the process energy use by state-of-the-art technologies. Improvements in the compression and separation sections could together lead to up to approximately 15% savings. Alternative processes, i.e. catalytic olefin technologies, can save up to approximately 20%. q

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An energy and greenhouse gas (GHG) balance study was performed on the production of the bioplastic polyethylene furandicarboxylate (PEF) starting from corn based fructose. The goal of the study was to analyze and to translate experimental data on the catalytic dehydration of fructose to a simulation model, using the ASPEN Plus modeling software. The mass and energy balances of the simulation model results were then used as inputs for a process chain analysis (by application of the life cycle assessment methodology, LCA) and compared to its petrochemical counterpart polyethylene terephthalate (PET). The production of PEF can be divided into three main units: the production of fructose from corn starch; the conversion of fructose into Furanics and subsequent recovery and upgrading; and the oxidation to the monomer 2,5-furandicarboxylic acid (FDCA) and polymerization with ethylene glycol (EG) into PEF. The ASPEN Plus simulation model describes the conversion of fructose into Furanics, subsequent recovery and upgrading and a CHP unit. The production of fructose from corn starch and the oxidation and polymerization into PEF were based on the literature. In total, six model cases were analyzed, using different sets of underlying experimental data; four cases based on crystalline fructose and two cases on high fructose corn syrup (HFCS). Fructose can be converted into Furanics at efficiencies between 38% and 47%. The production of PEF can reduce the NREU approximately 40% to 50% while GHG emissions can be reduced approximately 45% to 55%, compared to PET for the system cradle to grave. These reductions are higher than for other biobased plastics, such as polylactic acid (PLA) or polyethylene (PE). With an annual market size of approximately 15 million metric tonnes (Mt) of PET bottles produced worldwide, the complete bottle substitution of PEF for PET would allow us to save between 440 and 520 PJ of non-renewable energy use (NREU) and to reduce GHG emissions by 20 to 35 Mt of CO2 equivalents. If also substantial substitution takes place in the PET fibres and film industry, the savings increase accordingly. The GHG emissions could be further reduced by a switch to lignocellulosic feedstocks, such as straw, but this requires additional research

Biobased plastics have experienced fast growth in the past decade thanks to the public concerns over the environment, climate change and the depletion of fossil fuels. This perspective provides an overview of the current global market of biobased plastics, their material properties, technical substitution potential and future market (for 2020). In addition, the technology and market development of three biobased plastics, namely polylactide (PLA), biobased polyethylene (PE) and biobased epoxy resin, are discussed in detail. The emerging biobased plastics market is still small compared to traditional biobased polymers and biomaterials. The global capacity of the emerging biobased plastics was only 0.36 million tonnes in 2007. However, the market grew strongly between 2003 and 2007 (approx. 40% per year). The technical substitution potential of biobased plastics replacing petrochemical plastics is estimated at 90%, demonstrating the enormous potential of biobased plastics. Global capacity of biobased plastics is expected to reach 3.45 million metric tonnes in 2020. Starch plastics, PLA, biobased PE, polyhydroxyalkanoates (PHA) and biobased epoxy resin are expected to be the major types of biobased plastics in the future

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Bio-based succinic acid has the potential to become a platform chemical, i.e. a key building block for deriving both commodity and high-value chemicals, which makes it an attractive compound in a bio-based economy. A few companies and industrial consortia have begun to develop its industrial production on a large scale. A life cycle assessment of different bio-based succinic acid production processes, based on dextrose from corn, was performed to investigate their non-renewable energy use (NREU) and greenhouse gas (GHG) emissions, from cradle-to-factory gate in Europe. Three processes were studied, i.e. (i) low pH yeast fermentation with downstream processing (DSP) by direct crystallization, (ii) anaerobic fermentation to succinate salt at neutral pH (pH7) and subsequent DSP by electrodialysis, and (iii) a similar process producing ammonium sulfate as co-product in DSP. These processes are compared to the production of petrochemical maleic anhydride, succinic acid, and adipic acid. Low pH yeast fermentation to succinic acid with direct crystallization was found to have signifi cantly lower GHG emissions and NREU, compared to other fermentation routes and three petrochemical routes. However, the disparity in GHG emissions between this process and the electrodialysis process becomes less prominent if one considers a cleaner electricity mix than the current European production mix. Moreover, this study highlights that the allocation approach in corn wet milling and the succinic acid plant location strongly infl uence the results. Overall, the results suggest that low pH yeast fermentation with direct crystallization is the most benefi cial process to bio-based succinic acid from an environmental perspective.

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