Journal Issue: EnNRJ Vol. 17 No. 3
1
Issued Date
2019
Resource Type
Language
tha
eng
eng
File Type
application/pdf
Access Rights
open access
Rights
ผลงานนี้เป็นลิขสิทธิ์ของมหาวิทยาลัยมหิดล ขอสงวนไว้สำหรับเพื่อการศึกษาเท่านั้น ต้องอ้างอิงแหล่งที่มา ห้ามดัดแปลงเนื้อหา และห้ามนำไปใช้เพื่อการค้า
Rights Holder(s)
Faculty of Environment and Resource Studies Mahidol University
Journal Volume
EnNRJ Volume 17
(2019)
Articles
Use of Agricultural Residues to Remove Iron from Groundwater in Modified Airlift Aerator
(2019) Thanakrit Neamhom; Mahidol University. Faculty of Public Health. Department of Environmental Health Science
This work investigated groundwater iron adsorption capacity from rice husk, rice straw, water hyacinth and coconut shell, agricultural residues commonly found in Thailand. This study also investigated the adsorption behavior using an appropriate isotherm model in the batch process. The process was conducted using a modified airlift tray aerator. The use of a single adsorbent plate in a modified aerator obtained a removal capacity in the range of 0.3 to 0.9 mg/L, but the final iron concentration in the sample was above the regulatory standard. To increase the efficiency using the equivalent condition, the multiple adsorbent plate system was tested. The application of four rice husk plates achieved the allowance value and resulted in a final iron concentrationof 0.28 mg/L. Based on the results, iron was reduced by increasing the number of adsorbent plates. Hence, rice husk can be sustainably used to adsorb iron in groundwater. At equilibrium, the adsorption isotherm was fitted to the Freundlich equation with an R2value of 0.9805. This implied that the adsorption sites on the rice husk surface are heterogeneous in nature and presented a strong interaction between iron and rice husk. They revealed a maximum adsorption capacity of 0.73 mg/g. Moreover, this practice also decreased the amount of total hardness which could help alleviate nuisance and public health problems.
Acid-Catalyzed Esterification Pretreatment of High Free Fatty Acid Crude Rice Bran Oil for Biodiesel Production
(2019) Tin Mar Lar Thein; Jindal, Vinod K.; Ranjna Jindal; NuttawanYoswathana; Mahidol University. Faculty of Engineering. Department of Civil and Environmental Engineering; Mahidol University. Faculty of Engineering. Department of Chemical Engineering
This study investigated the acid-catalyzed esterification of two brands of crude rice bran oil (CRBO) with free fatty acids (FFAs) content of about 8 and 10%, respectively. Experimental variables included reaction time, methanol-to-FFA molar ratio and sulfuric acid content with temperature and stirring speed fixed at 60 °C and 600 RPM, respectively. A central composite design was used initially for sequential experimentation and followed by a Box-Behnken design to refine the optimum process conditions. Results showed that final FFA in CRBO could be reduced to less than 1% FFA in a single-step. The methanol-to-FFA molar ratio had the maximum influence on the esterification process and was followed by the reaction time and amount of catalyst. The optimum conditions for FFA conversion in CRBO were: reaction time 90 and 48 min, 62:1 and 70:1 methanol-to-FFA molar ratio, 22.5 and 20% (w/w) sulfuric acid based on FFA for Brand I and II, respectively. Under these pretreatment conditions, initial FFA was reduced to 0.61 and 0.70%, respectively making the CRBO suitable for biodiesel production.
Title
EnNRJ Vol. 17 No. 3
Author's Affiliation
Mahidol University. Faculty of Environment and Resource Studies
มหาวิทยาลัยมหิดล. คณะสิ่งแวดล้อมและทรัพยากรศาสตร์
มหาวิทยาลัยมหิดล. คณะสิ่งแวดล้อมและทรัพยากรศาสตร์
Keyword(s)
Climate change
Biodiversity
Disaster
Ecological
Environmental modelling
Environmental dynamics
Environmental pollution
Emerging contaminants
Transboundary pollution
Waste and wastewater treatments
Hazardous wastes
Natural resource management
Multidisciplinary sciences
Environment and Natural Resources Journal
Biodiversity
Disaster
Ecological
Environmental modelling
Environmental dynamics
Environmental pollution
Emerging contaminants
Transboundary pollution
Waste and wastewater treatments
Hazardous wastes
Natural resource management
Multidisciplinary sciences
Environment and Natural Resources Journal