Recent Innovations in Chemical Engineering - Online First

Bisphenol A (BPA) is an emerging environmental pollutant known for its harmful effects on living organisms. Consequently, the effective treatment of BPA-contaminated wastewater has garnered significant attention. This study utilized waste masks and cow dung as carbon-based raw materials. Subsequent co-pyrolysis treatment prepared the base biochar. Using thiourea as a nitrogen/sulfur source, N, S co-modified mask-based biochar (NSB) was successfully synthesized under high-temperature hydrothermal conditions.

Batch adsorption experiments confirmed NSB’s superior performance over unmodified materials. Adsorption characteristics of BPA were investigated using multiple isothermal models (Langmuir, Freundlich, Temkin, D-R) and kinetic models (Pseudo-first-order, Pseudo-second-order, Elovich, Intraparticle diffusion). Advanced characterization techniques, BET, XRD, SEM, FTIR, and XPS, were used to analyze NSB’s surface features before/after adsorption.

The results showed that NSB has a rich mesoporous structure and contains a large number of functional groups on its surface. The adsorption process of NSB on BPA is consistent with the Langmuir model and the Elovich model. The theoretical maximum adsorption capacity of BPA by NSB was calculated to be 42.77 mg·g^-1 by the Langmuir model.

This study indicates that the adsorption process is mainly a chemically-dominated, approximate monomolecular layer adsorption. The adsorption of BPA by NSB was synergistically driven by multiple mechanisms, which mainly included hydrogen bonding, π-π interactions, hydrophobic interactions, and pore filling.

The material NSB prepared in this study not only has a good effect on BPA treatment, but also can realize the resource utilization of waste materials. It not only provides new insights into the removal of BPA, but also provides a scientific basis for the design and application of new modified carbon materials.

This work focused on the successful preparation of a hand sanitizer with stable performance, mild hand feel, remarkable moisturizing effects, and antibacterial properties. The study aimed to explore the optimal formulation of the hand sanitizer by incorporating graphene, nanosilver, and chitosan, and evaluate its antibacterial efficacy against Escherichia coli.

The nanosilver solution was prepared using the chemical reduction method, where silver nitrate was reduced with a starch and sodium citrate dihydrate solution. To compare the antibacterial effects of different concentrations of graphene in the hand sanitizer, the viable count method was used for bacterial inhibition experiments using Escherichia coli. The types and amounts of the remaining components were determined using the controlled variable method. The prepared hand sanitizer was subjected to several tests, including stability, feel, pH, spectrophotometer, and viscosity coefficient tests.

The experimental results showed the hand sanitizer to be composed of 36% anhydrous ethanol, 3% glycerol, 17% sodium alginate (as a thickener), 0.50% essential rose oil, and a 1:1:1 ratio of graphene, nanosilver, and chitosan, exhibiting desirable properties. In particular, the hand sanitizer showed no delamination or precipitation. Its pH remained stable and moderate. It also showed a significant inhibitory effect on E. coli.

The incorporation of graphene, nanosilver, and chitosan into the hand sanitizer formulation contributed to its improved stability and antibacterial properties. The specific ratio of these components (1:1:1) was found to be optimal for achieving a balanced hand feel and effective moisturisation. Stability test results confirmed the absence of delamination and precipitation, indicating good physical stability. The moderate pH suggested the hand sanitizer to be kind to the skin. The antibacterial tests against E. coli further confirmed the effectiveness of the formulation in inhibiting bacterial growth.

The hand sanitizer prepared in this study, with a specific composition of 36% anhydrous ethanol, 3% glycerol, 17% sodium alginate, 0.50% rose essential oil, and a 1:1:1 ratio of graphene, nanosilver, and chitosan, showed excellent performance in terms of stability, hand feel, moisturisation, and antibacterial activity. This formulation has been found to have potential for practical applications in hand sanitization.

Studies using sustainable and environmentally friendly raw materials are prominent among researchers due to rising environmental concerns.

This study aimed to produce epoxidized corn oil using in situ peracid formation, with Amberlite IR-120H as a catalyst, alongside acetic acid and hydrogen peroxide.

Expoxidized corn oil was produced in situ with acetic acid as an epoxidation agent and Amberlite as a catalyst. Results: The results showed that using a 50% concentration of hydrogen peroxide and a 0.5:1 molar ratio of hydrogen peroxide to corn oil achieved the highest Relative Conversion to Oxirane (RCO).

In situ epoxidation resulted in a higher relative conversion to oxirane in reaction time (60 minutes).

Lastly, numerical simulations were executed employing a genetic algorithm, and the outcomes exhibited a noteworthy congruence between the simulated data and the empirical observations.