Research in Chemical Engineering (RiCE)

Reduction of Heavy Metal Levels (Pb and Fe) in Chemical Laboratory Wastewater by the Coagulation Method using Moringa Seeds Bio-coagulants (Moringa oleifera)

Elia Trisnawati, Neni Damajanti — Wed, 22 Nov 2023 00:00:00 +0000

Chemical laboratory wastewater treatment is important because contains hazardous wastewater substance that pollute the environment if not treated properly. Instead of to Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), and Biological Oxygen Demand (BOD) content, chemical laboratory wastewater also contains several types of heavy metals, such as Pb and Fe, which are infectious, pathological, and cytotoxic. One of the effective methods to treat the chemical laboratory wastewater is the coagulation-flocculation method with the addition of moringa seed powder bio-coagulant. The aim of this study was to determine the effect of coagulant dose and and precipitation time in reducing Pb and Fe metal levels in chemical laboratory wastewater. This study used variations in coagulant dose (1500, 2000, 2500, 3000, and 3500 mg/L) and precipitation time (20, 30, 40, 50, and 60 min). The result showed that the initial level of Pb and Fe in wastewater were 0.519 and 7.849 mg/L, respectively. The dose of 3000 mg/L of Moringa seed bio-coagulants showed the best concentration to reduce Pb level to 0.084 mg/L. On the other hand, at 3500 mg/L for reduction of Fe into 5.555 mg/L. The precipitation at 30 min showed the best time for reducing level both of Pb and Fe into 0.065 mg/L and 4.569 mg/L, respectively. However, the final level of Pb and Fe of wastewater after coagulation resulting in the below quality standard under The Minister of Environment Regulation Number 5 of 2014.

Synthesis of Hydrocarbon Through Pyrolysis of Used Lubricant with CaO

Endar Puspawiningtiyas, Renaldi Kuntara — Wed, 22 Nov 2023 00:00:00 +0000

The processing of used lubricants by pyrolysis with CaO was carried out. Pyrolysis was carried out at 375°C using a glass reactor. The effect of pyrolysis time and the addition of CaO on the pyrolysis of used lubricants was investigated. A SimDis (Simulated Distillation) analyzer is used to analyze the hydrocarbons of the pyrolysis products, while AAS is used to analyze the metal content. The results show that the addition of CaO to lubricating oil has an effect on increasing the yield, reducing the density, reducing the specific gravity, reducing the viscosity, reducing the metal content, reducing the acid number and increasing the recovery of the diesel/petrol content in hydrocarbons. The longer time during the pyrolysis process affects higher yield, higher density, higher specific gravity, higher viscosity, lower metal content and lower acid number. The results of the hydrocarbons obtained are 3 components, namely gasoline, aviation fuel and diesel. The dominant products of pyrolysis of used lubricants without CaO are diesel-type hydrocarbons (44.4%) and gasoline-type hydrocarbons with CaO (45.9%). The best results were obtained for waste oil samples with the addition of CaO, giving a yield of 72%, a density of 858.8 kg/m3, a specific gravity of 0.86, a viscosity of 17.01 cStokes, a Pb metal content of 0.522 mg/L and a Cu metal content of 0.292 mg/L. L, acid number 1.08 mg KOH/g, Simdis 44.38% diesel.

Apocarotenoids: Sources, Classification and Their Potential Application as Food Additives

Indah Hartati, Vita Paramita — Wed, 22 Nov 2023 00:00:00 +0000

Apocarotenoids are the degradation product of the enzymatic and or non enzymatic cleavage of carotenoids. Apocarotenoids are present in plants, fungi, bacteria and a certain animal species. There have been large numbers of apocaretonoids identified as the consequence of the great variety of naturally occurring carotenoids. Apocarotenoids can be found as volatile, semi-volatile or non-volatile compounds based on their chemical structures, while based on the number of the carbon atoms contained in their structure, apocarotenoids is classify into triporoids, cyclofarnesoids and methylhexanoids. Bibliometric analysis performed on publication having “apocarotenoids” keywords informs that crocin, pirocrocin, saffron and crocus sativus nodules appear in the overlay visualization. The appearance is attributed to the great potential application and commercialization of crocin which is originated from saffron. The bibliometric analysis also shows that there is food additive nodule appear which imply the strong correlation and potential application of apocarotenoids as food additive. The potential utilization and the commercial production of apocarotenoids are challenged by the the genetic diversity as well as the high cost, time consuming and seasonal production of natural apocarotenoids isolation process. Chemical synthesis, engineering biosynthesis and bio-manufacturing using microbes provide a promising and economical alternative.

Drying Methods Affecting the Antioxidant Activity of Turmeric Crude Drug

Sat, 25 Nov 2023 00:00:00 +0000

Turmeric is commonly a spice with many benefits in improving health, including antioxidants, anti-inflammatory and antimicrobial properties. The preparation of turmeric crude drug usually uses conventional sun drying. However, the quality of crude drugs is uncontrollable. The alternative using a modern drying process may affect the antioxidant properties of the final crude drug. This research aims to investigate the effect of drying methods (cabinet drying at 30^oC and 70^oC, infrared (IR), and conventional sun drying) on the antioxidant activity of turmeric crude drugs. The moisture content and its chemical compounds, including Total Phenolic Content (TPC) and Total Flavonoid Content (TFC), were also investigated. Antioxidant activity was measured using DPPH free radical scavenging and Feri Reducing Antioxidant Power (FRAP) method. The results showed that the moisture content of dried turmeric samples from cabinet drying at 70 C and sun drying was less than 10%. TPC of all dried turmeric from modern drying methods was significantly higher than conventional sun drying and the same as TFC results, except for the sample from the IR method. The antioxidant activity of dried curcumin from IR drying was significantly higher than that of another sample in the FRAP method. However, the higher antioxidant of dried turmeric using the DPPH free radical scavenging showed in dried turmeric from cabinet drying at 70 C and sun drying. The results of the antioxidant activity of the dried turmeric crude drug did not correlate with the TPC and TFC data as predicted using Pearson’s Correlation. Thus, it can be concluded that the drying methods influenced the antioxidant activity of turmeric crude drug, and it did not correlate with phenolic and flavonoid content.

Decaffeination of Coffee Bean Using Fermentation Process: Effect of Starter Concentration and Varieties on The Reduction of Caffeine and Antioxidant Activity

Alwani Hamad, Dwi Nugraheni, Bekti Wulan Sari, Mubshair Naveed — Sun, 26 Nov 2023 00:00:00 +0000

Coffee is a popular drink due to its special aroma and taste. Coffee contains caffeine that contributes a distinctive aroma to coffee, which can also be used as a quality parameter. However, if consumed excessively, it can have a negative impact on health. The decaffeination process using fermentation is one of the alternative methods to reduce the caffeine content without altering the characteristic taste and aroma of coffee. The objective of the study was to determine the influence of starter concentration (0-15%) and variety of coffee (Arabica and Robusta) in the decaffeination process using fermentation on reducing caffeine and the antioxidant activity of coffee products. The parameters were investigated regarding the chemical characteristics, including the concentration of caffeine, total flavonoid content (TFC), total phenolic content (TPC), and antioxidant activity tests using the DPPH free radical and FRAP methods. The results showed that the starter concentration and variety of coffee beans had a significant effect on the chemical characteristics (TPC and TFC) and antioxidant activity of decaffeinated coffee (p-value < 0.05). At a starting starter concentration of 5%, caffeine concentration was higher than a starter rate of 1% and did not significantly increase as stater up. Robusta coffee showed a higher decrease in caffeine compared to Arabica coffee.