CHEMICA: Jurnal Teknik Kimia

Optimization of Dyes Pollutant Adsorption Using KOH-Activated Eucalyptus Leaf Waste with Isotherm Adsorption Model

Dyan Hatining Ayu Sudarni — 2024-10-02

As with the rest of the production, the Batik industry hurts people's lives due to dyes. When discharged into the river, this dye will directly cause environmental pollution, one of which is the disruption of photosynthesis of aquatic plants and can cause disease for living things. Therefore, it is necessary to make efforts to overcome this. This study aims to determine the effect of adsorbent time variation and dose variation on methylene blue and malachite green adsorption. Adsorption is the absorption of solution molecules that occur on an adsorbent surface. The adsorbent used is Eucalyptus distillation leaf waste with KOH activation treatment using the Freundlich and Langmuir adsorption isotherm model. The measurement method uses UV-Vis spectrophotometry to analyze methylene blue and malachite green levels at the maximum wavelength. The results showed that the best % removal to adsorb methylene blue was 52.84% and malachite green 88.03% at a dose of 0.2 gram, and the optimum contact time to adsorb malachite green and methylene blue was 20 minutes. The adsorption Model in this study followed the Isotherm of Freundlich and Langmuir adsorption on malachite green with R2 of 0.872 and 0.612 for non-activation and 0.964 and 0.095 for KOH activation, while methylene blue obtained 0.636 and 0.143 for non-activation and 0.850 and 0.545 for KOH activation. Based on the study results, it was concluded that the distillation of Eucalyptus leaf waste is more effective in adsorbing malachite green.

Synthesis and Characterization of Activated Carbon from Trembesi Tree Stem Biomass (Samanea Saman)

Ervina Rumpakwakra — 2024-09-03

Biomass waste is currently being optimized to increase its use value and selling value on the market and reduce the impact of environmental pollution. Trembesi tree trunks (Samanea Saman) are waste that is often thrown away after being cut down. For this reason, this research has successfully utilized trembles tree trunk waste as active carbon using a KOH activator. The successful identification of active carbon synthesis was characterized using XRD, which showed an increase in crystal size from 9,902 nm to 14,207 nm. Functional group testing showed a relatively increased formation of carbon functional groups. The morphology of activated carbon shows an increase in pore size from 1537.1317 nm to 1597.3977 nm. The resulting surface area was 807,079 m2/g with an average pore size of 3.886 x 101 Å. These characterization tests provide important information for applying activated carbon on a wider scale.

Kinetic Study of the Degumming Process of Crude Turpentine Oil Using Phosphoric Acid

Dana Sisdikarini — 2024-11-22

Our study on degumming, a preliminary treatment commonly used in oil refining, and the specific method of acid degumming has practical implications. We investigate degumming turpentine's mass transfer and chemical reaction using phosphoric acid solutions, providing valuable insights for real-world applications. The experiment was conducted at a specific temperature (40, 50, 60, 70, and 80 °C), involving 100 ml of turpentine with 10 ml of 50% phosphoric acid solution in a stirred three-neck flask. The mixing was performed for 0, 30, 60, 90, and 120 minutes using a mechanical stirrer. The degumming process of turpentine follows a chemical regime, and the model provides a constant value for the mass transfer coefficient (K_cpa). The constant reaction rate in the acid phase (k) increases with temperature. This relationship can be represented by the equation provided. The equation is valid within the temperature range of 313 K to 353 K, with an average relative error of 0.9428.

Modeling and Simulation of Rice Husk Gasification using Equilibrium Approach

Yulnisma Ulfa — 2024-11-26

Gasification is a technique of changing solids into gases. So far, gasification has been widely used by utilizing coal, which contains many impurities like sulfur. Because of that, a gasification technology that utilizes biomass was developed. One of the biomass that is often found in Indonesia is rice husk. This research will use an equilibrium approach to study rice husk gasification modeling and simulation using the Aspen Plus v8.8 simulator. In addition, the influence of the number of gasification agents, such as steam and air, and gasification temperature was also studied in this research. The amount of steam used is expressed in the steam-to-biomass ratio (SBR), while the amount of air used is expressed in the equivalence ratio (ER). This study uses SBR 0.4 and 0.6, ER 0.4 and 0.6, and gasification temperatures of 750oC and 850oC. From this study, if the SBR is increased, the amount of H2 will also be greater. Meanwhile, the increase in ER will reduce the amount of H2 and CO in synthetic gas. The higher gasification temperature will increase the CO composition but decrease the H2 gas content.

Characterization of Natural Zeolite Modified through High-Temperature Heating and KNO3 Addition

Rani Pramudyo Ningtyas — 2024-09-03