Oil palm empty fruit bunch (OPEFB) is a potential raw material abundantly available for bioethanol production. However, the second-generation bioethanol is still not yet economically feasible. The COVID-19 pandemic increases the demand for ethanol as the primary ingredient of hand sanitisers. This study evaluates the techno-economic feasibility of hand sanitiser production using OPEFB-based bioethanol. OPEFB was alkaline-pretreated, and simultaneous saccharification and fermentation (SSF) was then performed by adding Saccharomyces cerevisiae and cellulose enzyme. The cellulose content of the OPEFB increased from 39.30% to 63.97% after pretreatment. The kinetic parameters of the OPEFB SSF at 35 °C, which included a µ max, ks, and kd of 0.018 h−1, 0.025 g/dm3, and 0.213 h−1, respectively, were used as input in SuperPro Designer® v9.0. The total capital investment (TCI) and annual operating costs (AOC) of the plant were $645,000 and $305,000, respectively, at the capacity of 2000 kg OPEFB per batch. The batch time of the modelled plant was 219 h, with a total annual production of 32,506.16 kg hand sanitiser. The minimum hand sanitiser selling price was found to be $10/L, achieving a positive net present value (NPV) of $108,000, showing that the plant is economically feasible.

Gelatin is utilised as a nitrogen source to synthesise nitrogen (N)-doped carbon nanotubes (CNTs). The N-doped CNT was prepared by mixing gelatin and CNT, followed by calcination at 500 °C and 800 °C under N2 atmosphere. X-ray diffraction analysis shows that the higher gelatin weight ratio results in a decrease of the crystallisation. X-ray photoelectron spectroscopy deconvolution analysis confirms that pyridinic-N and pyrrolic-N have appeared at the surface of the samples. The higher calcination temperature affects the surface properties of N-doped CNT which tend to shift the pyrrolic-N to the pyridinic-N. Cyclic voltammetry analysis reveals that the presences of pyridinic-N and graphitic-N configuration have higher oxygen reduction reaction (ORR) activity compared to the N-pyrrolic structure.

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Contradictions have been reported on the effect of organic solvents, especially toluene, on enzymatic ring-opening polymerization (eROP) of L-lactide. Studies have shown that log P, a common measure of hydrophilicity, affects enzyme activity. This study examines the effect of solvents with various log P values on the eROP of L-lactide, performed using Candida rugosa lipase (CRL). N,N-dimethylacetamide (DMA), 1,2-dimethoxybenzene, 1,4-dimethoxybenzene, diphenyl ether, and dodecane were used as the organic solvents. The eROP in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) was also conducted to compare its performance with the organic solvents. The results show that [BMIM][PF6]− mediated eROP gave better conversion and molecular weight than the organic solvent-mediated eROP. In this study, the effects of solvents hydrophilicity are discussed, including the possibility of hexafluorophosphate ion ([PF6]−) hydrolysis to occur.

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