Claim Missing Document
Check
Articles

Found 24 Documents
Search

Validation of Methylene Blue Analysis Method in Wastewater Samples by UV-Vis Spectrophotometry Hulupi, Mentik; Keryanti, Keryanti; Rahmawati, Karina Aulia; Dewi, Widya Tresna; Abdilah, Fauzi
Equilibrium Journal of Chemical Engineering Vol 7, No 2 (2023): Volume 7, No 2 December 2023
Publisher : Program studi Teknik Kimia UNS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/equilibrium.v7i2.75807

Abstract

Abstract. Methylene blue (MB) is an extensively utilized cationic dye in the textile industry. MB is, however, a highly noxious substance that can have detrimental effects on both the environment and human health. MB can pollute waterways and cause the mortality of aquatic organisms in the environment. Due to the hazards posed by MB, it is crucial to have an effective method for analyzing its concentration in wastewater. This will ensure that MB-contaminated water is appropriately treated and disposed of, thereby protecting the environment and human health. One of the analyses utilized the Evolution 360 UV-Vis Spectrophotometer to determine methylene blue concentrations. The Evolution 360 UV-Vis Spectrophotometer method was validated by measuring linearity tests, limit detection and quantization, precision, and accuracy. The R-value for linearity measurements is greater than 0.99, indicating that the method is proportionally validated. As required, the precision measurement yields acceptable results, with a %RSD value of less than 2%, and the accuracy measurement yields a recovery of 100% (between 80 and 110%). So that the method for measuring the concentration of methylene blue in water using the UV-Vis Evolution 360 Spectrophotometer satisfies the requirements for linearity, precision, and accuracy.Keywords:Analysis, Methylene Blue, Method Validation, Spectrophotometer
Hydrolysis of Waste Cooking Oil Using Rhizopus oryzae to Produce Free Fatty Acids Rintis Manfaati; Prans Connery Manurung; Muhamad Nur Rojab; Keryanti Keryanti
Fluida Vol. 16 No. 1 (2023): FLUIDA
Publisher : Department of Chemical Engineering, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v16i1.4496

Abstract

Waste cooking oil is waste produced from palm oil after it has been heated and fried at high temperatures, and it can pollute the environment. One effort to reuse waste cooking oil is a fermentation processe that produces free fatty acids with the help of Rhizopus oryzae as a biocatalyst. Variations in initial substrate concentration ranged from 10 g/L to 70 g/L, followed by varied types of nitrogen sources, namely malt extract, beef extract, (NH2)2CO, NH4Cl, and (NH4)2SO4 at a concentration of 70 g/L to determine free fatty acid concentration. Fermentation was carried out for 7 days. The analysis carried out included the concentration of free fatty acids, biomass, and YP/X value. The optimum initial used cooking oil substrate was obtained at a concentration of 30 g/L with a YP/X value of 13.63%, a free fatty acid concentration of 2.13 g/L and a dry cell weight of 15.48 g/L. The best nitrogen source is beef extract with a Yp/x value of 11.78%, a free fatty acid concentration of 2.02 g/L and a dry cell weight of 17.0 g/L
Biogasoline Production from Shallot Skin Waste with KOH-Clay Catalyst to Create Clean Energy Keryanti Keryanti; Dhea Nurul Amalia; Anindya Indrita Putri; Della Agustia Marhani; Putri Vina Amalia; Anwar Muhamad Rizki
Fluida Vol. 16 No. 2 (2023): FLUIDA
Publisher : Department of Chemical Engineering, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v16i2.4591

Abstract

Finding alternative fuels to replace fossil fuels has been made easier by the rise in the consumption of fuels like petrol and the fall in the production of national petroleum exploration activities. This research has been prompted using biomass as an alternative fuel. The primary raw material is shallot skin waste because it has enough lignocellulosic content to be used, one of which is to manufacture biogasoline by using the characteristics of petrol E10. A KOH-Clay catalyst is employed in a thermal and catalytic reaction to influence the reaction's pace. Starting with raw material preparation, conversion procedure, purification, and investigation of the physical properties of biogasoline at specific temperature fluctuations for an hour, the KOH-Clay catalyst is pretreated and characterised. It was discovered through this research that the montmorillonite KOH-Clay content was 5.73, indicating that the catalyst is hygroscopic and absorbs non-polar molecules, making it suitable for use as a catalyst with a pH of 6. As a result, at 60°C temperature circumstances, the best%yield results were attained of 35.025%. While the density value (0.950 gr/cm3) and colour (specific gravity, brownish yellow, and clear/bright) of the experimental results do not meet predetermined standards, they do when viewed from the viewpoint of physical parameters such as specific gravity (0.8358), oAPI biogasoline (37.794), and calorific value (18807.65 Btu/Ib). However, leftover shallot peels generally have the potential to be utilised as clean renewable energy.
The Effect of Papaya Leaf Concentration and Fermentation Time on The Decafeination Process of Robusta Coffee Tri Hariyadi; Keryanti Keryanti; Nurisa Salsabila; Sarah Sarah
Fluida Vol. 16 No. 2 (2023): FLUIDA
Publisher : Department of Chemical Engineering, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v16i2.5441

Abstract

High level of caffeine in Robusta coffee requires the reduction of level to accommodate person with low caffeine tolerance. The wet fermentation process with papaya leaf extract containing the papain enzyme was used to decaffeinate the coffee. This study aimed to investigate the effects of papaya leaf extract concentration and sampling time on the decaffeination of Robusta coffee green beans. The papaya leaf extract concentration ranged from 10% to 80% (w/v), with fermentation lasting 6 to 72 hours. The caffeine content was measured using a UV-Vis spectrophotometer, and organoleptic tests were performed on 40 untrained panelists. The results showed that both the concentration of papaya leaf extract and the fermentation time influenced the decaffeination. The optimum result was obtained after 48 hours of fermentation with 80% (w/v) papaya leaf extract resulting in a caffeine content of 0.268% (w/w) from an initial content of 1.20% (w/w), representing a 77.82% decrease in caffeine level efficiency. Fermented coffee was preferred by 58% of panellists over unfermented coffee. These findings imply that papain found in papaya leaves can reduce caffeine levels while also improving flavor and aroma.