| The demand for energy security and climate change mitigation encourages the development of sustainable production pathways.Currently,emerging production pathways of organic chemicals taken biomass and CO2 as feedstock attract increasing interests.However,immature technologies,high production costs and low reaction efficiencies are challenges to develop these processes.The concept design,process modelling,techno economic analysis,and life cycle assessment are generally used to verify technical feasibility,identify the opportunity and barriar,and provide the improvement strategies to underpin the sustainable development.Herein,olefins(ethylene and propylene),ethylene glycol,long-chain alkane,and cyclohexane-derived chemicals are taken as representative demonstrations to explorer application prospects of sustainable production pathways from view of technical,economic,energy-related and climate impact.Techno-economic analysis and life cycle assessment of twenty light olefin production pathways has been investigated through literature review and process modelling.The results show that sustainable production pathways of light olefins have potential to save energy and reduce carbon emissions,but higher product cost compared to fossil production pathways.Furthermore,research strategies,i.e.carbon capture and storage,scale expansion,and feedstock price fall,are used to explore the perspective of different olefin pathways.Furthermore,the development tendency of ethylene industries in China was analysed,and this real-time change and different pathways were integrated to explorer how to hit peak CO2 emissions by 2030.A practical solution through development of sustainable pathways with approximately 1.1%of growth ratio per annual is proposed.Bio-derived ethylene glycol attracts interests owing to renewability of feedstock and high atom economy of the reaction process.However,bio-derived ethylene glycol still remains lab-scale and limited available work about industrial performance has been reported.The process model and evaluation system of bio-derived ethylene glycol was designed and established.The technical performance,economic benefit,fossil energy depletion,and global warming potential of bio-derived ethylene glycol was evaluated through process modelling,techno-economic analysis and life cycle assessment.Research strategies for the optimization of product yield,substrate concentration,dehydration technologies,raw material collection efficiency,and hydrogen sources,were subsequently investigated to maximize the benefits of bio-EG.In addition,a carbon tax was investigated to reach economic benefits of bio-derived ethylene glycol.This work bridges the lab scale experiment and industrial application.Long-chain alkanes are the major components in diesel.Based on the photocatalytic decarboxylation process from fatty acid into long-chain alkanes,process model of conversion of soybean fatty acids into diesel has been designed and an early-stage analysis is conducted through life cycle assessment.The results disclose that this process present economically unattractive currently,and scenarios analysis was conducted to provide improvement suggestion through optimization of electricity generation sources,radiant efficiency,apparent quantum efficiency,and mass ratio of solvent to substrate.The life cycle assessment of 1,4-cyclohexanedimethanol,1,4-cyclohexanedicarboxylic acid and 1,2-cyclohexanedicarboxylates was conducted and the results show that high ratio of solvent to substrate and makeup solvent in biomass pretreatment process account for the major contribution to life cycle climate impacts.Sustainable production pathways have been dramatically developed but subject to immature technologies,which results in high production costs even high fossil energy depletion and greenhouse gas emissions.Therefore,development of efficient reaction,advance process,and emerging technology are encouraged in future researches. |
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