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Microwave-assisted solvent extraction of castor oil from castor seeds 被引量:4
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作者 Nur Atirah Ibrahim Muhammad Abbas Ahmad Zaini 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2516-2522,共7页
This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at diff... This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) ratios.The process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield. 展开更多
关键词 CASTOR SEED CASTOR oil DIELECTRIC properties MICROWAVE-ASSISTED SOLVENT extraction OXIDATION stability
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Relationship between Helium Degassing of Cattle-Manure-Compost Adsorbents and Copper Ions Removal
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作者 Muhammad Abbas Ahmad Zaini Mohd Azizi Che Yunus +1 位作者 Yoshimasa Aman Motoi Machida 《International Journal of Organic Chemistry》 2012年第3期262-266,共5页
This work was aimed to investigate the effect of helium degassing of cattle-manure-compost (CMC) based activated carbons on the adsorptive removal of copper ions from aqueous solution. Degassing temperatures were 500... This work was aimed to investigate the effect of helium degassing of cattle-manure-compost (CMC) based activated carbons on the adsorptive removal of copper ions from aqueous solution. Degassing temperatures were 500℃, 800℃ and 1000℃. Activated carbons were characterized according to surface chemistry and pore structures. Adsorption of copper ions was carried out using the conventional bottle-point technique to which the equilibrium data were correlated to Langmuir and Freundlich models. Results indicated that the uptake of copper ions could be well characterized by Langmuir model. It was found that the adsorption of copper ions decreased with significant decrease in surface area as a result of helium degassing at higher temperature. The increase of electron density on graphene layers offered higher affinity towards copper ions at lower equilibrium concentration. It was inferred that copper ions favorably adsorbed on mesopores at lower equilibrium concentration and switched to micropores at higher equilibrium concentration. 展开更多
关键词 ACTIVATED Carbon Adsorption Copper Ions Cattle-Manure-Compost HELIUM DEGASSING
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New generation Amberlite XAD resin for the removal of metal ions: A review 被引量:1
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作者 Akil Ahmad Jamal Akhter Siddique +4 位作者 Mohammad Asaduddin Laskar Rajeev Kumar Siti Hamidah Mohd-Setapar Asma Khatoon Rayees Ahmad Shiekh 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第5期104-123,共20页
The direct determination of toxic metal ions, in environmental samples, is difficult because of the latter's presence in trace concentration in association with complex matrices, thereby leading to insufficient sensi... The direct determination of toxic metal ions, in environmental samples, is difficult because of the latter's presence in trace concentration in association with complex matrices, thereby leading to insufficient sensitivity and selectivity of the methods used. The simultaneous removal of the matrix and preconcentration of the metal ions, through solid phase extraction,serves as the promising solution. The mechanism involved in solid phase extraction(SPE)depends on the nature of the sorbent and analyte. Thus, SPE is carried out by means of adsorption, ion exchange, chelation, ion pair formation, and so forth. As polymeric supports, the commercially available Amberlite resins have been found very promising for designing chelating matrices due to its good physical and chemical properties such as porosity, high surface area,durability and purity. This review presents an overview of the various works done on the modification of Amberlite XAD resins with the objective of making it an efficient sorbent. The methods of modifications which are generally based on simple impregnation, sorption as chelates and chemical bonding have been discussed. The reported results, including the preconcentration limit, the detection limit, sorption capacity, preconcentration factors etc., have been reproduced. 展开更多
关键词 Amberlite XAD Toxic metals Chelating resin Preconcentration Sorption capacity
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