ADSORPTION OF Zn AND Pb METAL IN PRINTING WASTE OF PT. GRAFIKA WANGI KALIMANTAN USING CORN COBS CHARCOAL AS ADSORBENT

Heavy metals produced from several industrial processes cause many environmental problems. Efforts made to overcome this heavy metal pollution include adsorption methods. Agricultural by-products have the potential as an adsorbent, one of which is corn cobs. In this study, corncobs were used as Pb and Zn adsorbents. The purpose of this study was to determine the effect of particle size and stirring speed in the process of Zn and Pb metal absorption using activated charcoal. Adsorption was done by mixing 100 mL waste of PT. Grafika Wangi Kalimantan with 10 grams of activated charcoal measuring 355 micron, 500 micron and 710 micron. Each mixture is stirred for 15 minutes at speeds of 30, 60, 90, and 120 rpm and then allowed to stand for 3 hours. Analysis of the absorbed Zn and Pb metal content was carried out using a spectrophotometer at adjusted wavelengths. The greater the stirring speed, and the small size of the active charcoal particle used, decrease of Zn and Pb levels is increasing due to the better absorption of adsorbate by the adsorbent. The biggest decrease in Zn and Pb levels was seen at a stirring speed of 90 rpm and the active charcoal particle size of 355 microns where the Zn and Pb parameters contained in the sample were <0.01 mg / L.

Arang Aktif dari Ampas Kopi sebagai Absorben Logam Cu Terlarut dalam Skala Laboratorium

Pencemaran logam berat Tembaga (Cu) di lingkungan perairan laut saat ini semakin meningkat. Logam berat ini memberikan dampak negatif bagi biota dalam perairan laut dengan menjadi penghambat pertumbuhan hingga menyebabkan kematian. Arang aktif dari ampas kopi dapat dimanfaatkan sebagai salah satu bioadsorben yang efektif. Penelitian mengenai penggunaan ampas kopi sebagai bioadsorben telah banyak dilakukan. Penelitian ini bertujuan untuk mengetahui kemampuan daya serap oleh arang aktif ampas kopi dengan lama perendaman dan konsentrasi yang berbeda terhadap logam berat Tembaga (Cu). Penelitian ini dilakukan pada tanggal 3 Juni – 18 Juli 2018. Metode yang digunakan ialah metode eksperimental laboratoris. Aktivasi adsorben dilakukan menggunakan HCl 0,1 M selama 48 jam. Kemudian arang aktif dikeringkan pada suhu 1100C selama 3 jam untuk meningkatkan daya serapnya. Berdasarkan analisa Atomic Absorption Spectrophotometric (AAS) yang telah dilakukan diperoleh daya serap arang aktif dengan konsentrasi 0,5 gr, 1 gr, dan 2 gr dengan masing-masing lama perendaman 15 menit, 30 menit, 60 menit, 90 menit, dan 120 menit berturut-turut adalah 99,28 %; 95,70 %; 98,79 %; 99,50%; 97,98 %; 95,39 %; 98,66 %; 99,46 %; 99,92 %; 97,04 %; 96,83 %; 98,57 %; 99,94 %; dan 99,96 % dengan kecepatan pengadukan 150 rpm. Konsentrasi adsorben dan lama perendaman yang berbeda terhadap larutan logam Cu diketahui berpengaruh nyata terhadap penyerapan logam berat Cu (p<0,05) oleh arang aktif. Terdapat penurunan daya adsorpsi arang aktif pada lama perendaman 30 menit kemudian tetap mengalami kenaikan daya adsorbsi terhadap logam Cu dengan semakin lama lama perendaman serta semakin tinggi konsentrasi adsorben yang digunakan. Pollution of heavy metals Copper (Cu) in the marine environment is currently increasing. This heavy metal has a negative impact on biota in marine waters by becoming a growth inhibitor that causes to death. Activated charcoal from coffee wastes can be used as an effective bio-adsorbent. Research on the use of coffee wastes as bio-adsorbent has been widely studied. This study aims to knowing the ability of activated charcoal from coffee wastes to absorb heavy metal of copper (Cu) using different immersion times and different concentrations of activated charcoal. The study was conducted on June 3 - July 18, 2018. The method used in this study was an experimental laboratory method. Activation of the adsorbent was carried out using 0.1 M HCl for 48 hours. Then the activated charcoal is dried at 1100C for 3 hours to improve the adsorption capacity of the adsorbent. Based on the analysis of Atomic Absorption Spectrophotometric (AAS), the absorption of activated charcoal has been obtained with concentrations of 0.5 gr, 1 gr, and 2 gr with contact time of 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes are 99.28%; 95.70%; 98.79%; 99.50%; 97.98%; 95.39%; 98.66%; 99.46%; 99.92%; 97.04%; 96.83%; 98.57%; 99.94%; and 99.96% with a stirring speed of 150 rpm. The concentration of the adsorbent and the different immertion times for copper (Cu) solutions significantly affected the absorption of Cu heavy metals (p <0.05) by activated charcoal. There was a decrease in activated charcoal adsorption power at the immertion time of 30 minutes and continued to increase the adsorption power of Cu metal with the longer immertion time and the higher the concentration of the adsorbent used.

Biodiesel Production from Waste Cooking Oil Purified with Activated Charcoal of Salak Peel

Biodiesel is one of diesel fuel alternative made from renewable resources such as vegetable oils and animal fats. One of the natural ingredients that can be used as a material in the production of biodiesel is waste cooking oil (WCO). Biodiesel from WCO can be made through a transesterification reaction using a CaO catalyst. Free fatty acid (FFA) content in WCO needs to be reduced by activated charcoal adsorption. This research aims to determine the optimum time of adsorption by activated charcoal that made from salak peel and to determine the effect of transesterification temperature on biodiesel yield. The results showed that the FFA content of WCO decrease from 6.16% to 0.224% with adsorption time is 80 minutes and 10 gram of activated charcoal. Biodiesel yield increase by increasing transesterification temperature. The appropriate temperature is 50oC with 86.40% of yield, 887.2 kg/m3of density, 5.174 mm2/s of kinematic viscosity and acid number 0.421 mg KOH/gram sample. The composition of alkyl ester was obtained 65.54% with a FAAE yield of 56.63%.

ISOLASI OLIGOSAKARIDA MADU LOKAL DAN ANALISIS AKTIVITAS PREBIOTIKNYA

The objective of this study was to isolate oligosaccharides from local honey of Pulau Sumbawa and province of Kalimantan Timur and to analyze its prebiotic activity in vitro. Oligosaccharides were isolated with activated charcoal adsorption and ethanol treatment. Effectiveness of this method was evaluated by Thin Layer Chromatography and colorimetry. The isolates were then being a sample to prebiotic examination. Honey from Sumbawa forest has higher oligosaccharides content than honey from Kalimantan. Qualitative and quantitative assays showed that oligosaccharide isolation method was effective to concentrate the oligosaccharide with high degree of polymerization but ineffective for mono- and disaccharides removal. The highest percentages of hydrolysis of oligosaccharide from Sumbawa and Kalimantan by mimic gastric juice were 1.78% and 0.59 %. Whereas, the hydrolysis was higher with amylase, 11.87% for Sumbawa and 21.03% for Kalimantan honey oligosaccharides. Prebiotic activity was 0.32, and 0.09 for honey oligosaccharide from Sumbawa and Kalimantan respectively. Honey oligosaccharide from Sumbawa presented higher prebiotic activity than inulin as prebiotic reference (0.11). GC-MS chromatogram showed L. acidophilus cultured in media added with Sumbawa honey oligosaccharide produced lactic acid as the highest metabolite (48.01%).

Temperature Effects Associated with the Adsorption of Neodymium Ions onto Activated Charcoal

The temperature dependence of the kinetics of the adsorption of neodymium ions from aqueous solution onto activated charcoal has been studied. The results obtained indicate that a form of equilibration appears to be attained after ca. 30 min although further very slow changes may occur over a much longer period. The adsorption process is controlled by the diffusion of neodymium ions into the pores of the activated charcoal. Adsorption follows first-order kinetics with an activation energy of 13.09 kJ/mol. Values of the equilibrium constant for the adsorption of neodymium ions onto activated charcoal increase with increasing temperature, thereby indicate the endothermic nature of the process.