scholarly journals Effect of Tithonia diversifolia extract on the biodegradability of the bioplastics in plantation soil (Pengaruh ekstrak Tithonia diversifolia terhadap biodegradabilitas bioplastik di tanah perkebunan)

2018 ◽  
Vol 86 (2) ◽  
Author(s):  
. ISROI ◽  
Nendyo A WIBOWO ◽  
Evi SAVITRI ◽  
Deden D ERIS ◽  
Agus PURWANTARA
Keyword(s):  
Carbon Dioxide ◽  
Methyl Orange ◽  
Sodium Hydroxide ◽  
Tithonia Diversifolia ◽  
Plastic Sample ◽  
Biodegradation Test

Effect of Tithonia diversifoliaextract on biodegradability of the bioplastic was evaluated using plantation soil as natural inoculum. The bioplastic was a composite of cellulose from cacao pod husk, starch and enriched by tithoniaextract. Biodegradation test wasereconducted in the glass jar for 60 days. The carbon dioxide generated from the biodegradation test titrated by 0.1 N sodium hydroxide solutions. The carbon dioxide was measured with 0.1 N HCl and using phenolphthalein followed by methyl orange as indicator. Carbon dioxide was detected in the bioplastic samples but not detected in the conventional plastic sample during the test. Biodegradation of the bioplastic enriched by tithoniaextract was higher than  that of the bioplastic without tithoniaextract. Biodegra-dation rate of the bioplastic samples in plantation soil were 0.068 mg CO2/day and 0.178 mg CO2/day for the bioplastic without and with tithoniaextract, respectively. Biodegradation of the bioplastic samples for 45 days were 12.44% and 28.07% for the bioplastic without and with tithoniaextract, respectively. Complete biodegradation of the bioplastic predicted in 244 days and 200 days for the bioplastic without and with tithoniaextract, respectively. [Kata kunci :Tithonia diversifolia, biodegrada-bility, bioplastic, plantation soil]. AbstrakPengaruh ekstrak Tithonia diversifoliaterhadap biodegradabilitas bioplastik dievaluasi dengan menggunakan tanah perkebunan sebagai inokulum alami. Bioplastik yang digunakan adalah komposit selulosa dari kulit buah kakao, pati dan diperkaya dengan ekstrak tithonia. Uji biodegra-dasi dilakukan di dalam botol selama 60 hari. Karbon dioksida yang dihasilkan dari uji biodegradasi diserap oleh larutan natrium hidroksida 0,1 N. Karbon dioksida dititrasi dengan HCl 0,1 N dan menggunakan fenolftalein diikuti dengan metil jingga sebagai indikator. Karbon dioksida terdeteksi pada sampel bioplastik namun tidak terdeteksi pada sampel plastik konvensional.Bioplastik yang diperkaya dengan ekstrak tithonia menghasilkan tingkat biodegradasi yang lebih tinggi dari pada bioplastik tanpa ekstrak tithonia. Tingkat biodegradasi sampel bioplastik di tanah perkebunan adalah 0,068 mg CO2/hari dan0,188 mg CO2/hari masing-masing untuk bioplastik tanpa dan dengan ekstrak tithonia. Biodegradasi sampel bioplastik selama 45 hari adalah 12,44% dan 28,07%berturut-turutuntuk bioplastik tanpa dan dengan ekstrak tithonia. Biodegradasi keseluruhan bioplastik diperkirakan membutuh-kan waktu 244 hari dan 200 harimasing-masinguntuk bioplastik tanpa dan dengan ekstrak tithonia.[Keywords:Tithonia diversifolia, biodegradaibi-litas, bioplastik, tanah perkebunan].

SIGNIFICANT EFFECT OF PH ON PHOTOCATALYTIC DEGRADATION OF ORGANIC POLLUTANTS USING SEMICONDUCTOR CATALYSTS

2016 ◽  
Vol 78 (8-3) ◽  
Author(s):  
Nur Farhana Jaafar ◽  
Aishah Abdul Jalil ◽  
Sugeng Triwahyono ◽  
Adnan Ripin ◽  
Mohamad Wijayanuddin Ali
Keyword(s):  
Carbon Dioxide ◽  
Methyl Orange ◽  
Physicochemical Properties ◽  
Photocatalytic Degradation ◽  
Organic Pollutants ◽  
Ph Value ◽  
Effect Of Ph ◽  
Electrolysis Method ◽  
Ph Range ◽  
Positively Charged

Photocatalytic is one of the inexpensive and non-toxic techniques for degradation of organic pollutants into harmless substances such as water and carbon dioxide. In this study, simple electrolysis method was used in preparation of Ag/TiO2 and α-Fe2O3/HY catalysts. The physicochemical properties of the catalysts were studied using XRD, FTIR, FESEM-EDX and surface area analysis. The pH of solution plays an important role in the photocatalytic degradation of organic pollutants which influences the surface-charge properties of the catalysts. Ag/TiO2 and α-Fe2O3/HY were used as catalyst on degradation of 2-chlorophenol (2-CP) and methyl orange (MO), respectively. The effect of pH on degradation of 2-CP and MO were investigated over a pH range from 2 to 9. Higher degradation of 2-CP and MO were obtained at pH 5 (74%) and pH 2 (80%), respectively. This finding might be explained by the amphoteric performance of the catalyst using point zero charge (pHZPC). The pHZPC for Ag/TiO2 and α-Fe2O3/HY was found to be at pH 6.3 and pH 7.2, respectively. Hence, the activities of the catalysts may have been affected by the existence of a strong electrostatic field between the positively charged catalysts surface and negatively charged 2-CP and MO caused a pH value lower than their pHZPC give greater degradation.

The Measurement of the Oxygen Consumption of Daphnia by a Modification of the Cartesian Diver Technique

1948 ◽  
Vol 25 (4) ◽  
pp. 313-321
Author(s):  
R. J. O'CONNOR
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Sodium Hydroxide ◽  
Modified Technique ◽  
Sources Of Error ◽  
Rate Of Oxygen Consumption ◽  
Total Capacity

1. The Cartesian diver microrespirometer has been adapted to the measurement of the oxygen consumption of Daphnia. The modification involves an increase in size of the diver to a total capacity of over 100 µ1., and absorption of carbon dioxide by sodium hydroxide in a central cup incorporated in the structure of the diver. 2. The variation in the rate of oxygen consumption of normal Daphnia has been measured. 3. Sources of error in the modified technique have been investigated and the possibility of its wider use discussed.

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