Purpose In converting lignocellulosic biomass into biofuel, a pretreatment stage is required in order to make the biomass more readily available for the transformation. There are numerous pretreatment techniques that can be chosen, which are broken down into four categories: chemical, physical, physicochemical, and biological. The aim of this work is to provide a new assessment for some of the emerging technologies using life cycle assessment (LCA) combined with an analysis of the overall product yield. Methods Using literature data, an LCA of four different pretreatment methods was carried out. Liquid hot water (LHW), steam explosion (SE), dilute acid (DA), and organosolv (OS) were chosen as the most common techniques with high scalability potential. Models were constructed using GaBi software. A cradle-to-gate analysis was selected with a common model of the corn stover growth and harvesting cycle being combined with the individual models for each pretreatment. Four impact categories were analyzed, and a selection has been discussed based on relevance to the biofuel production process. Results and discussion In nearly all of the impact categories, DA performs the worst due to the length of the process (12 h) and the amount of electricity required to elevate the temperature to 60°C for that time period. In many of the other categories, the remaining three pretreatments perform comparably to each other with the exception of LHW which has significantly reduced CO 2 emissions. LHW has slightly higher water depletion rates than both SE and OS, which is to be expected given the nature of the process. In terms of product yield, LHW produced twice as much total sugar than any of the other processes. Conclusions The project concluded that while LHW and SE are viable options for the pretreatment of biomass, LHW is the most suitable technique for the pretreatment of corn stover. This pretreatment was environmentally friendly as it produced the lowest CO 2 emissions, aligning with the main objective behind developing biofuels from agricultural residues. The process was also technically the most effective as it resulted in the highest sugar yields.

Several problems with stabilization of electricity grid system are related to the time lag between the electricity supply and demand of the end users. Many power plants run for a limited period of time to compensate for increased electricity demand during peak hours. The amount of CO2 generated by these power installations can be substantially reduced via the development of new demand side management strategies utilizing CO2 absorption units with a short start-up time.The sorbent can be discharged using radiofrequency (RF) heating to fill the night-time valley in electricity demand helping in the stabilization of electricity grid. Herein a concept of RF heated fixed bed reactor has been demonstrated to remove CO2 from a flue gas using a CaCO3 sorbent. A very stable and reproducible operation has been observed over twenty absorptiondesorption cycles. The application of RF heating significantly reduced the transition time required for temperature excursions between the absorption and desorption cycles. The effect of flow reversal during desorption on desorption time has been investigated. The desorption time was reduced by 1.5 times in the revered flow mode and the total duration of a single absorption-desorption cycle was reduced by 20%. A reactor model describing the reduced desorption time has been developed. 2 Highlights• An RF reactor system has been demonstrated for post-combustion carbon capture.• The transition time between the absorption and desorption cycles was reduced by 2 times as compared to conventional heating• The reverse CO2 desorption flow mode reduced the desorption time by 1.5 times.• The energy efficiency of RF heated and conventionally heated bench reactors was compared

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