Achmad Chafidz

Fatty Acid Methyl Ester (FAME) or palm oil methyl ester is one of the palm oil derivatives in which one of the anionic surfactants that can be generated from it is methyl ester sulfonate (MES). This bio-based surfactant can reduce the interfacial tension (IFT) between oil and water. To produce a bio-based polymeric surfactant, sulfonate groups from MES were grafted onto polymer chains. Palm oil methyl ester was reacted with sulfuric acid (H2SO4) to synthesize MES. Afterwards, MES was reacted with the Ethyl Acrylate (EA) monomer to synthesize polymeric surfactant. Investigating this route to produce a bio-based polymeric surfactant has become the novelty of this study. This study showed that the best polymerization result was obtained at a mole ratio of MES to EA (1:0.5) with the highest viscosity of 14.47 mm2/s. The critical micelle concentration (CMC) analysis showed 0.5% at a mole ratio of MES to EA (1:0.5) which corresponded to the lowest interfacial tension (IFT) of 1.95 x 10-3 mN/m. Meanwhile, the contact angle gradually decreased from 58.44 to 11.79°. The polymeric surfactant, furthermore, was analyzed using FTIR and H-NMR and successfully confirmed the formation of bio-based polymeric surfactant. The core flooding experiment found that approximately 16.57% of oil could be recovered. The results of the study revealed a good potential of the polymeric surfactant to be applied in chemical enhanced oil recovery (CEOR).

Plastic waste is the main problem that causes environmental pollution due to its non-biodegradable properties. One of the efforts to overcome this problem is th

In this study, bioplastics made of Konjac glucomannan have been successfully prepared via film casting method. The effects of addition of beeswax content (i.e. of 0%, 0.5%, and 1%,), as well as glycerol content (i.e. 0.5%, 1%, and 1.5%) on the properties of the bioplastics have been investigated. The bioplastics produced have been characterized for their tensile strength, percent elongation, swelling degree, and biodegradability. The results of this study, showed that most of the bioplastic samples have weight loss of about 95% after the drying process as well as the finished film. The addition of beeswax and glycerol concentrations also increased tensile strength and percent elongation of the bioplastics. The highest value of tensile strength occurred at bioplastic film with a concentration of 1.5% beeswax and 1% glycerol (i.e. Sample C3) with a value of approximately 3.5 MPa. Whereas, the highest percent elongation value occurred at bioplastic film with a concentration of 1.5% beeswax and 1% glycerol (i.e. Sample C3) with a value of approximately 23.29%. These tensile and percent elongation values were higher or comparable to other bioplastic samples made from starch of different raw materials reported by literatures. In the other hand, the addition of beeswax and glycerol decreased the degree of swelling. The degree of swelling for all the bioplastic film samples were in the range of 316.77 – 481%.

Polypropylene filled calcium carbonate (CaCO₃) nanocomposites were fabricated by employing melt blending/compounding method using masterbatch. To investigate the efffect of reprocessing on the melting properties of PP/CaCO₃ nanocomposites, the melt compounding process was conducted twice (two cycles). The effect of nano-CaCO₃ loadings (i.e. 5, 10 and 15 wt%) on the melting properties of PP/CaCO₃ nanocomposites were also studied. The meling properties of the nanocomposites were analyzed by using a DSC (Differential Scanning Calorimetry). Additionally, the nanocomposites samples were also analyzed by an SEM (Scanning Electron Microscopy). The SEM analysis results revealed that at higher nano-CaCO₃ loading (i.e. 15 wt%), the nano-CaCO₃ particles in the 2^nd cycle were more well distributed/dispersed in the polypropylene matrix as compared to the 1^st cycle. Whereas, the DSC test results showed that the crystallinity of the nanocomposites samples were similar to that of neat PP for the 1st cycle of melt blending process, which was about 41%. In the other hand, for the 2^nd cycle, the crystallinity of the samples slightly increased wtih increasing nano-CaCO₃ loadings, which were about 39.6; 43; 44% for nano-CaCO₃ loadings of 0, 5, 10 wt%, respectively. Nevertheless, at the highest nano-CaCO₃ loadings (i.e. 15 wt%), the crystallinity of the nanocomposites (i.e. NCC-15-II) decreased again and lower than that of neat PP, which was about 37.7%.

Energy is an important parameter in the social and economic development of a country. Thus, it is necessary to seek renewable energy to supply energy needs in Indonesia. The production of bioethanol from microalgae as a biofuel is one way to reduce the use of fossil fuels. Microalgae has an advantage over other types of biomass sources due to its high biomass productivity and do not compete with agricultural crops for land and water resources. In the bioethanol production process, the ethanol and water form an azeotrope mixture of 95.6% of ethanol at 1 atm and 78.15°C. The objective of this research was to analyse and determine the operating conditions and the optimum distillation column configuration which results in high ethanol purity according to fuel specifications (fuel grade ethanol). The method of pressure-swing distillation was applied to separate the azeotrope of ethanol-water and obtain high purity ethanol. A simulation model of bioethanol production with pressure-swing distillation system was conducted by using Aspen Plus V10. In this research, the influence of process parameters such as distillation column pressure, reflux ratio, feed stage location, and the number of theoretical stages was analysed by using model analysis tools. The results showed that the obtained bioethanol purity of 99.9% with the condenser and reboiler duty of the LP column -79.931 kW and 667.651 kW, respectively; while the HP column is -47.627 kW and 57.698 kW.

The purpose of this study was to determine and compare the effect of oven drying and spray drying treatments on the encapsulation of anthocyanin, flavonoid and phenolic extracted from watermelon rind. The analysis done in this work were as follow: total anthocyanin (TA), total flavonoid (TF) and total phenolic (TPC) content in the supernatant, yield of nanocapsule, Particle Size Analysis, and In Vitro test (test for flavonoid and phenolic release) in the supernatant food. The analysis results showed that the total anthocyanin content in watermelon rind with a spray drying treatment was 0.1113 mg/L, total flavonoid was 0.6159 g/mL, and total phenolic was 0.3410 g/mL. While using the oven, the anthocyanin content was 0.0891 mg/L, total flavonoid was 1.4590 g/mL, and total phenolic was 1.1349 g/mL. As noticed, the total content of anthocyanin resulted by using a spray dryer was greater than by using an oven. However, the total flavonoid and total phenolic resulted by using a spray dryer was smaller than by using an oven. During In Vitro analysis, the results of the release of flavonoid and phenolic resulted by using an oven into the distilled water were much larger and unstable than by using a spray dryer. This is likely because chitosan-Na (TPP) bonds are weak. Additionally, the yield of capsule on the use of spray dryer was 0.6, higher than the use of an oven, which was 0.48. While, the average particle size in the use of a spray dryer was 2.296 μm, smaller than the use of an oven, which was 61.998 μm.

Industrial waste containing heavy metals can pollute the aquatic environment. One method that can be done to manage heavy waste is the adsorption method that uses adsorbent from cassava stem powder. This research was conducted to utilize cassava stem powder waste for the adsorption of Pb2 + metal ions. Cassava stem powder was mashed until it passed 100 mesh sieve. Cassava stems have a cellulose content of 70-80%, lignin 15-20%, ADF 15-20% and cellulose can be used as an absorber of heavy metals. The adsorption process is carried out with variations in pH, time and concentration under optimum conditions. In this adsorption involves the functional groups contained therein so that the interaction between the adsorbent with the metal ion Pb2 +. Based on the research, the optimum conditions were obtained at pH 6, 180 minutes contact time and 50 ppm concentration. This test is carried out using Atomic Absorption Spectroscopy (AAS).