Thermochemical Conversion of Untreated and Pretreated Biomass for Efficient Production of Levoglucosenone and 5-Chloromethylfurfural in the Presence of an Acid Catalyst

Levoglucosenone (LGO) and 5-chloromethyl furfural (5-CMF) are two bio-based platform chemicals with applications in medicines, green solvents, fuels, and the polymer industry. This study demonstrates the one-step thermochemical conversion of raw and pretreated (delignified) biomass to highly-valuable two platform chemicals in a fluidized bed reactor. Hydrochloric acid gas is utilized to convert biomass thermochemically. The addition of hydrochloric acid gas facilitates the formation of LGO and CMF. Acid gas reacts with biomass to form 5-CMF, which acts as a catalyst to increase the concentration of LGO in the resulting bio-oil. The presence of higher cellulose content in delignified biomass significantly boosts the synthesis of both platform chemicals (LGO and CMF). GC-MS analysis was used to determine the chemical composition of bio-oil produced from thermal and thermochemical conversion of biomass. At 350 °C, the maximum concentration of LGO (27.70 mg/mL of bio-oil) was achieved, whereas at 400 °C, the highest concentration of CMF (19.24 mg/mL of bio-oil) was obtained from hardwood-delignified biomass. The findings suggest that 350 °C is the optimal temperature for producing LGO and 400 °C is optimal for producing CMF from delignified biomass. The secondary cracking process is accelerated by temperatures over 400 °C, resulting in a low concentration of the target platform chemicals. This work reveals the simultaneous generation of LGO and CMF, two high-value commercially relevant biobased compounds

Development of a thermal model for a hybrid photovoltaic module and phase change materials storage integrated in buildings

The performance of building integrated photovoltaic modules (PV) situated outdoors suffers from attained high temperatures due to irradiation as a negative temperature coefficient of their efficiency. Phase change materials (PCMs) are investigated as an option to manage the thermal regulation of photovoltaic modules and, hence, enhance their electrical efficiency. In this study a transient one-dimensional energy balance model has been developed to investigate the thermal performance of a photovoltaic module integrated with PCM storage system. Possible all heat transfer mechanisms are described to have a basic and step by step fundamental knowledge to analyze and understand the complex heat transfer characteristics of the PV-PCM system. Finite difference scheme is applied to discretize the energy balance equation while fully implicit scheme is applied to discretize the heat balance in the PCM module. Three different PCM of different melting temperatures were investigated. The numerical result is validated with experimental studies from the literature. The result indicates that PCM are shown to be an effective means of limiting the temperature rise in the PV devices thus increasing the thermal performance up to 5%