Synthesis of magnetic nanocarbon using palm oil as the green precursor via microwave-assisted arc for wastewater treatment.

The presence of metal with microwave irradiation has always invited controversial arguments as the metal will catch on fire easily. But interestingly, researchers found that arc discharge phenomena provide a promising way for molecule cracking to synthesize nanomaterials. This study developed a single-step yet affordable synthesis approach that combines microwave heating and arcing in transforming crude palm oil into magnetic nanocarbon (MNC), which can be considered a new alternative for the palm oil sectors. It involves synthesizing the medium at a partial inert condition with constant coiled stainless steel metal wire (dielectric media) and ferrocene (catalyst). This approach successfully demonstrates heating at a temperature ranging from 190.9 to 472.0 °C with different synthesis times (10-20 min). The produced MNC shows formations of spheres with average sizes of 20.38-31.04 nm, mesoporous structure (SBET: 14.83-151.95 m2/g), and high content of fixed carbon (52.79-71.24wt%), and the ratio of the D and G bands (ID/IG) is 0.98-0.99. The formation of new peaks in the FTIR spectra (522.29-588.48 cm-1) supports the appearance of the FeO compounds from the ferrocene. The magnetometer shows high magnetization saturation (22.32-26.84 emu/g) in ferromagnetic materials. The application of the MNC in wastewater treatment has been demonstrated by evaluating their adsorbent capability with Methylene Blue (MB) adsorption test at a different concentrations varying between 5 and 20 ppm. The MNC produced at synthesis time (20 min) shows the highest adsorption efficiency (10.36 mg/g) compared to others, with 87.79% removal of MB dye. As a result, the value for Langmuir is not promising compared to Freundlich, with R2 being around 0.80, 0.98, and 0.99 for MNC synthesized at 10 min (MNC10), 15 min (MNC15), and 20 min (MNC20), respectively. Hence, the adsorption system is in a heterogeneous condition. The microwave-assisted arcing thereby presents a promising approach to transforming CPO into MNC that could remove the hazardous dye.

A review of the recent trend in the synthesis of carbon nanomaterials derived from oil palm by-product materials.

Grown only in humid tropical conditions, the palm tree provides high-quality oil essential for cooking and personal care or biofuel in the energy sector. After the refining process, this demand could cause numerous oil palm biomass waste management problems. However, the emergence of carbon nanomaterials or CNMs could be a great way to put this waste to a good cause. The composition of the palm waste can be used as a green precursor or starting materials for synthesizing CNMs. Hence, this review paper summarizes the recent progress for the CNMs production for the past 10 years. This review paper extensively discusses the method for processing CNMs, chemical vapor deposition, pyrolysis, and microwave by the current synthesis method. The parameters and conditions of the synthesis are also analyzed. The application of the CNMs from palm oil and future recommendations are also highlighted. Generally, this paper could be a handy guide in assisting the researchers in exploring economic yet simple procedures in synthesizing carbon-based nanostructured materials derived from palm oil that can fulfill the required applications.