Jurnal Teknik Kimia

Optimization of CO2 methanation process using Ni-Fe/Al2O3 catalyst at low temperatures

Yurika Dewi Safitri Liza — 2024-07-24

Carbon dioxide is one of the major contributors to the greenhouse effect. According to IEA data, energy-related carbon dioxide emissions increased by 6 % in 2021 to 36.3 billion tonnes. Methanation of carbon dioxide, known as the Sabatier reaction, is an exothermic reaction in which hydrogen and carbon dioxide react to form methane and water as a by-product. Methane is a colorless, odorless, non-toxic but flammable and hazardous gas. Nickel, Rhodium, and Ruthenium catalysts are some of the most widely used active catalytic constituents in CO₂ methanation. Al₂O₃, SiO₂, CeO₂, ZrO₂, TiO₂, Nb₂O₅, and combinations of other constituents have been widely proposed and studied as catalyst supports. In this study, a Nickel catalyst was used with a combination of Al₂O₃as a support and Fe as a promoter. The Nickel catalyst was chosen because it can absorb hydrogen, is cheap, and is very selective in methane formation. This study was conducted in situ, by reacting 1 gr, 2 gr, and 3 gr of Ni catalyst powder; 1 gr, 2 gr, and 3 gr of Al powder; Fe powder as much as 1 gr and 2 gr with 1 M NaOH solution which is heated while stirring at a speed of 100 rpm for 60 minutes. The highest methane gas yield was obtained in sample 10 with a mass of Ni, Al, and Fe respectively 3 gr, 1 gr, and 2 gr of 10.07 % with a CO₂ conversion of 2.70 %. The more Ni and Fe catalyst

Application of integrated adsorption method (oil palm fiber, activated carbon, and ultrafiltration) in hospital wastewater treatment

M. Fazrin Pramavada — 2024-08-15

Hospital wastewater contains various pollutants including organic and inorganic compounds, heavy metals, and microorganisms which pose environmental and health risks. In Indonesia, the volume of hospital wastewater is increasing, whereas wastewater effluent hasn’t met wastewater quality standard optimally. Conventional wastewater treatments require high-cost, large areas, long operating times, and produce sludge. Previous studies showed that adsorption and filtration effectively decreased Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), and total coliform levels of hospital wastewater. Activated carbon is widely used adsorbent, but oil palm fiber offers higher adsorption capacity due to its cellulose and lignin content. It’s abundant, renewable, low-cost, and eco-friendly adsorbent. Meanwhile, filtration membrane has high adsorption capacity, but it gets saturated quickly and needs pre-treatment process. This study analyzes the effectiveness of integrated adsorption method in hospital wastewater treatment. It was a quasi-experimental study with one group pre-test post-test design. Wastewater from Hospital X in Palembang was treated with oil palm fiber, activated carbon, and ultrafiltration after being deposited for 24 hours. There were four trials. The combination of oil palm fiber, activated carbon, and ultrafiltration shows promising result with removal efficiency percentage of pH by 8.91 %; BOD by 60.53 %; COD by 57.52 %; TSS by 84.21 %; and total coliform by 52.50 %. Each adsorbent has specific role: oil palm fiber significantly decreases BOD (47.37 %) and TSS (80 %) levels; activated carbon effectively decreases COD (58 %) and total coliform (60%) levels; and ultrafiltration effectively decreases TSS level (83.58 %).

The effect of Used Cooking Oil (UCO) pre-treatment using bagasse on Free Fatty Acid (FFA) content

Nina Haryani — 2024-07-31

Used Cooking Oil (UCO) refers to cooking oil that has been previously used. UCO can be reused through impurity removal and reduction of the FFA high content. The reduction of FFA content in UCO can be achieved using the adsorption method, employing adsorbents derived from various materials such as agricultural waste and zeolite. Examples of agricultural waste suitable for this purpose include rice husks, straw, and bagasse, the latter of which can serve as a natural adsorbent. This study aimed to investigate the impact of UCO pre-treatment on FFA content. The research comprised three stages: preparation, adsorption, and analysis. Initially, the FFA content in UCO was 5.50 %. The pre-treatment of UCO involved using bagasse with varying stirring speeds (0, 150, 200 rpm) and adsorption temperatures (70, 85, 100 ^oC). Optimal pre-treatment conditions were identified, with the most significant reduction in FFA to 1.49 % observed at 200 rpm and 100 ^oC. The utilization of bagasse as a natural adsorbent effectively reduces the high FFA content in UCO as part of its pre-treatment process.