Jurnal Rekayasa Kimia & Lingkungan
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EFFECT OF THE ADDITION OF ORANGE PEEL POWDER ON THE PHYSICAL AND MECHANICAL PROPERTIES OF POLYLACTIC ACID (PLA)/CELLULOSE ACETATE (CA) FILM COMPOSITES
Full text linkConventional plastics are already a popular packaging material in society, but they have a harmful influence on the environment. As a result, there is a need for environmentally friendly polymers that are raw from nature and biodegradable alternatives to traditional plastics, one of which is raw plastic Polylactic Acid (PLA) coupled with Cellulose Acetate (CA) and Tween 80 as a compatibilizer. The goal of this research was to find the best ratio of orange skin powder to PLA/CA with the compatibilizer Tween 80 to improve the physical, mechanical, and antibacterial properties of the composite film. The method used is solvent casting with a mass ratio of PLA/CA 6: 4 with the addition of Tween 80 2%, and the addition of orange peel powder with variations of 2, 4, 6, and 10 % w/w to the weight of PLA. The tests carried out include FTIR, SEM, XRD, DSC-TGA, mechanical tests (tensile strength and elongation at break), swelling tests, and antibacterial tests. The results showed that the PLA/CA/Tween 80 film composite has a fairly smooth surface with a small cavity, capable of degrading to a temperature of 546.57C. Regarding the mechanics, the best film composites were identified at a variation of 6% with tensile strength of 4.05 MPa and elongation at break reaching 11.2% with a fairly small water absorption and this variation did not show antibacterial activity
PREPARATION AND CHARACTERIZATION OF FLY ASH ADDITIVE MODIFIED POLIESTER BASED MEMBRANE
Full text linkRecently, Polyethersulfone (PES) polymer material based on flat sheet membranes reached much attention in membrane technology. However, PES polymer has low hydrophilicity. This study describes PES-based membranes incorporating fly ash as an additive. The first analysis was conducted by Fourier Transform Infrared, Scanning Electron Microscope, tensile strength, and porosity tests. Four membranes, including pure PES membranes, were prepared via the phase inversion process, namely MA0, MA0.1, MA1, and MS1. The characteristics of the membrane samples were analyzed in terms of chemical group, morphology, mechanical and membrane surface hydrophilicity. The characterization results show that additive incorporation increased pure water flux performance, and the highest pure water permeability increased up to 70% by the MA1 membrane. Moreover, it increased by 19% compared to pure silica-modified PES membrane (MS1). In addition, the MA-1 membrane at a pressure of 3 bar reached significant performance in the trend of pure water flux values because of these improvements in membrane characteristics. The membrane also shows a higher tensile strength with adding additives to the membrane prepared
ANALYSIS OF WATER QUALITY AND QUALITY STATUS IN ACEH RIVERS BASED ON ENVIRONMENTAL POLLUTION INDEX
Full text linkThe rapid development of industrialization and urbanization in the world impact increased water pollution. Human activities, such as dam constructions, excessive water consumption, severance of river flows, compaction of riverbanks, and excessive use of riverbed vegetation, disrupt river flow and alter the original hydrological cycle. In response to these conditions, this study aims to analyze water quality and river quality status to set up a watershed environmental management strategy in Aceh Province as a case study. River water quality was analyzed descriptively by comparing the results of laboratory tests with parameters, namely TSS, pH, BOD, COD, DO, total phosphate, nitrate, and fecal coli. These parameters were then transformed into the environmental index (Water Quality Index and Pollution Index). It was found that Water Quality Index (WQI) results are shown from 50 to 70. WQI with the Good category is at Kr. Weh which is in the Central Aceh city. The medium-less type is found in 10 watersheds. The water quality with the category of Less is found at 3 points, namely Kr. Aceh, Cr. Doy, and Cr. Daroy. The quality of the river water in the Aceh region, from upstream to downstream, has decreased in quality with a lightly polluted status based on the Minister of Environment and Forestry of the Republic of Indonesia No. 27 of 2021 for class II
Microalgae as A Bioremediation Agent for Palm Oil Mill Effluent: Production of Biomass and High Added Value Compounds
Full text linkPalm oil mill effluent (POME) is high strength wastewater obtained from palm fruit processing, which contains high chemical oxygen demand (COD), biological oxygen demand (BOD), and other contaminants. The pollutant load in POME can serve as a source of nutrients for microalgae growth. As a result, the goal of this work was to utilize Spirulina sp. and Nannochloropsis oculata to reduce the nutritional content of POME while producing biomass rich in high-value chemicals. The cultivation was conducted in a batch reactor using various POME fractions (0-20%) under 5,000 lux light intensity and continuous aeration at a temperature of 22-28C and a salinity of 30 ppt for 14 consecutive-days. The results demonstrate that Spirulina sp. produced the most biomass at 15% POME, accounting for 4.670.95 g/L with 0.570.11 1/day of growth rate and 3.33% of COD reduction efficiency. Meanwhile, Nannochloropsis oculata thrived in 20% POME, producing 4.430.36 g/L biomass, 1.180.31 1/day growth rate, and 14.43% COD reduction efficiency. In the proximate analysis. Spirulina sp. and Nannochlorpsis oculata provided 0.87%; 1.11% lipid and 1.03%; 0.86% protein, respectively
The Effect of Borax Addition as Buffering Agent on Storage Stability of Melamine-Formaldehyde Resin in the Production of High-Pressure Laminates
Full text linkHigh-pressure laminates (HPL) is one of the applications of thermosetting resins for wood-based materials as protective and decorative panels covering building furniture. Melamine-formaldehyde (MF) resin is one of the resins that play a role in the production of high-pressure laminates. This resin has low storage stability due to cross-linking between free melamine methylols accompanied by a decrease in pH during the storage process. This study aims to improve the storage stability of melamine-formaldehyde resin by adding borax as a buffering agent. Synthesis of MF resin was conducted by polymerization and condensation steps followed by the addition of borax at concentrations of 0, 0.5, 1, 1.5, and 2% when the endpoint was reached. The characterization of the resin includes the analysis of the physical and chemical parameters of the resin and the analysis of the functional groups of the resin by FT-IR. Storage stability study of MF resin was carried out by daily visual observation and determination of daily changes in pH and viscosity. MF resin was further used in the production of high-pressure laminates. High-pressure laminates characterization includes quality analysis based on SNIISO4586-7:2017 and analysis gloss level. In this study, 1.5% MF borax resin had the highest storage stability, namely 11 days. HPL quality analysis complies with SNIISO4586-7:2017 standards. High-pressure laminates of 1.5% borax MF resin has the highest gloss level, which is 115
Effect of Solid to Solvent Ratio and Extraction Time on Yield, Phytochemical Content and Physicochemical of Amla (Phyllanthus emblica) Seed Oil Extracted using Hexane
Full text linkAmla (Phyllanthus emblica) seeds have only been disposed of as waste and have not been utilized optimally. Utilizing the seeds to produce oil has been regarded as a promising approach for reducing solid wastes and producing value-added products. This study evaluated the effect of solid to solvent ratio and extraction time on yield, phytochemical content and physicochemical of oil extracted from amla seed using hexane as a solvent. The amla seed oil was extracted through the solid-liquid process at different solid to solvent ratios (1:20, 1:25 and 1:30 g/mL) and extraction times (30, 60, 90 and 120 minutes). The highest yield found was 10.97% at a solid to solvent ratio of 1:30 (g/mL) and an extraction time of 120 minutes. The highest concentrations of phenolic compounds and flavonoids were 66.12 mg GAE/g and 95.70 mg QE/g respectively, obtained at a solid to solvent ratio of 1:25 (g/mL) and extraction time of 120 minutes. Physicochemical analysis (pH, density, acid number, free fatty acid, and peroxide number) showed that the quality of extracted oil was better than what the previous study reported. In the amla seed oil, the content of unsaturated fatty acids was higher than saturated fatty acids with linoleate as the main component. These results clarified that solid-liquid extraction method can be used for extracting amla seed oil and also indicated that amla seed oil can be used as an ingredient in health-related industry products
Adsorption of Methylene Blue by Graft Copolymer Acrylamide onto Pineapple Peel Cellulose with the Addition of Activated Carbon Microwave-Assisted
Full text linkCationic dyes such as methylene blue are among the most widely used dye in the textile and paper industry. The dye waste produced causes environmental pollution and is harmful to human health. Thus, wastewater treatment becomes an important aspect of reducing this problem. Adsorption is a very effective method for treating various wastewaters due to its high selectivity and capacity. This study aims to prepare an adsorbent from graft copolymer acrylamide onto cellulose with the addition of activated carbon microwave-assisted and to test its performance as an adsorbent for methylene blue. The adsorbent synthesis was carried out using a microwave-assisted graft copolymer technique. The graft of acrylamide onto cellulose with the addition of activated carbon was carried out at various times (3, 4, and 5 minutes). Based on the FTIR spectra characterization of the adsorbent, the functional groups are C=O and N-H, and SEM analysis shows that the surface forms an interconnected network. At 3, 4, and 5 minutes of irradiation, grafting ratios were 329.72, 128.00, and 150.12, with grafting efficiency of 99.74, 72.94, and 78.02%. The maximum adsorption capacity of the adsorbent on methylene blue was 14.00, 6.04, and 9.97 mg/g, respectively, following the Langmuir isotherm model and pseudo second order kinetics. The experimental results show that the adsorbent can effectively remove or eliminate methylene blue in an aqueous solution
Membrane Modification with Polydopamine to Improve Performances A Mini Review
Full text linkThis paper provides an overview of some studies and investigations regarding the utilization of polydopamine as an additive in membrane fabrication. Polydopamine is widely used due to its high hydrophilicity and adhesive properties. The addition of polydopamine in to the membrane system mostly attributed to the improvement of membrane performance in terms of permeation, antifouling, and antibiofouling
Modification of Polyvinylidene Fluoride (PVDF) Membrane by Polymer Blending with Phase Inversion Method
Full text linkOne of the simplest approaches to improve membrane performance is to increase the hydrophilicity of the membrane. This article describes the manufacture of activated polyvinylidene fluoride (PVDF) based membranes using PVP and chitosan as organic additives, with the specific aim of increasing the hydrophilicity of the membranes. Variations of dope solution were made by adding 1% by weight of PVP and 1, 2, and 3% by weight of chitosan into three different PVDF polymer solutions. The effect of additives on the membrane was obtained by evaluating chemical functional groups by ATR-FTIR, morphological changes by SEM, and filtration performance. SEM images show that the presence of additives changes the morphological structure of the membrane. This change also had a significant impact on the membrane performance, as evidenced by the increased permeability of the pure water solution and the removal of dissolved humic acid. Overall, modified PVDF membranes with 1% by weight of PVP and 1, 2, and 3% by weight of chitosan resulted in much better permeability than unmodified PVDF membranes due to their excellent hydrophilicity
Coffee Improvement by Wet Fermentation Using Lactobacillus plantarum: Sensory Studies, Proximate Analysis, Antioxidants, and Chemical Compounds
Full text linkFermentation has been developed to produce a distinctive taste in food, one of which is coffee. Fermentation affects the quality and taste of coffee in coffee beans. This study conducted coffee fermentation using Lactobacillus plantarum bacteria, isolates of Lactic Acid Bacteria. The research method begins with the preparation of Lactobacillus plantarum inoculants which will be used for coffee fermentation, fermentation, total phenol and flavonoid content, caffeine content, chlorogenic acid content, compound analysis, antioxidants, and proximate analysis. Total phenol and flavonoid, caffeine, chlorogenic acid, and antioxidant using the UV-VIS Spectrophotometer instrument. In addition, compound analysis is carried out using GC-MS. This study showed that the bacterium Lactobacillus plantarum would hydrolyze sucrose into simpler sugars with the enzyme invertase and produce organic acids through glycolysis. Liberica coffee fermented using Lactobacillus plantarum bacteria contains phenol compounds, flavonoids, antioxidants, and compound compounds higher than Original Liberica coffee. Meanwhile, the caffeine and chlorogenic acid of Liberica coffee fermented using Lactobacillus plantarum bacteria are lower than Original Liberica coffee. Overall, the chemical compounds of Liberica coffee that have been fermented using Lactobacillus plantarum bacteria are better than Original Liberica Coffee. Liberica coffee beans fermented using Lactobacillus plantarum bacteria have better physical quality and taste than Original Liberica coffe