17 research outputs found
Techno-economic and life-cycle assessment of volatile oil extracted from Aquilaria sinensis using supercritical carbon dioxide
Extracts of Aquilaria sinensis possess pharmacological activity that has been widely used in traditional medicines since ancient times. In this study, techno-economic assessment was conducted for extraction of volatile oil from abundant biomass (lignified ring) and resin of A. sinensis to evaluate their respective economic feasibility using supercritical carbon dioxide (SC-CO2) extraction in Malaysia. The assessment revealed that for a production capacity of 5280 kg/y volatile oil, the total capital investment (TCI) was 81.96 million and 0.025 million/kg and $ 0.0125 million/kg, respectively. Both volatile oil extracted from resin and lignified ring showed a positive net profit which indicated their profitability. In addition, a cradle-to-gate analysis of life-cycle assessment (LCA) was performed, whereby the extraction process contributed the highest impact towards the environment due to its high energy consumption. Nevertheless, this study estimated that the process might reduce the environmental impacts by approximately 90% when the technology readiness levels (TRLs) reach the level of 9–10. These findings are beneficial in providing preliminary insights in terms of economic and environmental aspects for volatile oil extraction using SC-CO2 technology
Recovery of cellulose fibers from oil palm empty fruit bunch for pulp and paper using green delignification approach
The aim of this work was to recover the cellulose fibers from EFB using low-transition-temperature-mixtures (LTTMs) as a green delignification approach. The hydrogen bonding of LTTMs observed in 1H NMR tends to disrupt the three-dimensional structure of lignin and further remove the lignin from EFB. Delignification process of EFB strands and EFB powder were performed using standard l-malic acid and cactus malic acid-LTTMs. The recovered cactus malic acid-LTTMs showed higher glucose concentration of 8.07 mg/mL than the recovered l-malic acid LTTMs (4.15 mg/mL). This implies that cactus malic acid-LTTMs had higher delignification efficiency which led to higher amount of cellulose hydrolyzed into glucose. The cactus malic acid-LTTMs-delignified EFB was the most feasible fibers for making paper due to its lowest kappa number of 69.84. The LTTMs-delignified EFB has great potential to be used for making specialty papers in pulp and paper industry
Uncertainty estimation approach in catalytic fast pyrolysis of rice husk : Thermal degradation, kinetic and thermodynamic parameters study
The aim of this study was to understand the influence of catalyst in thermal degradation behavior of rice husk (RH) in catalytic fast pyrolysis (CFP) process. An iso-conversional Kissinger kinetic model was introduced into this study to understand the activation energy (EA), pre-exponential value (A), Enthalpy (ΔH), Entropy (ΔS) and Gibb’s energy (ΔG) of non-catalytic fast pyrolysis (NCFP) and CFP of RH. The study revealed that the addition of natural zeolite catalyst enhanced the rate of devolatilization and decomposition of RH associated with lowest EA value (153.10 kJ/mol) compared to other NCFP and CFP using nickel catalyst. Lastly, an uncertainty estimation was applied on the best fit non-linear regression model (MNLR) to identify the explanatory variables. The finding showed that it had the highest probability to obtain 73.8–74.0% mass loss in CFP of rice husk using natural zeolite catalyst
Fractionation and extraction of bio-oil for production of greener fuel and value-added chemicals : Recent advances and future prospects
Bio-oil is a highly valuable product derived from biomass pyrolysis which could be used in various downstream applications upon appropriate upgrading and refining. Extraction and fractionation are two promising methods to upgrade bio-oil by separating the complex mixture of bio-oil compounds into distinct fine chemicals and fractions enriched in certain classes of chemical compounds. In this review, various extraction techniques for bio-oil (organic solvent extraction, water extraction, supercritical fluid extraction, distillation, adsorption, chromatography, membrane, electrosorption and ionic liquid extraction), their associated features (extraction mechanisms involved, advantages and disadvantages), the characteristics of bio-oil extracts and their applications are presented and critically discussed. It was revealed that the most promising technique is via organic solvent extraction. Furthermore, the technological gaps and bottlenecks for each separation techniques are disclosed, as well as the overall challenges and future prospects of oil palm biomass-based bio-oil value chain. This review aims to provide key insights on bio-oil upgrading via extraction and fractionation, and a proposed way forward via technology integration in establishing a sustainable palm oil mill-based biorefinery
Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c
Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose
diabetes, but may identify different people as having diabetes. We used data from 117
population-based studies and quantified, in different world regions, the prevalence of
diagnosed diabetes, and whether those who were previously undiagnosed and detected
as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed
prediction equations for estimating the probability that a person without previously
diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa.
The age-standardised proportion of diabetes that was previously undiagnosed, and
detected in survey screening, ranged from 30% in the high-income western region to 66%
in south Asia. Among those with screen-detected diabetes with either test, the agestandardised
proportion who had elevated levels of both FPG and HbA1c was 29-39%
across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and
middle-income regions, isolated elevated HbA1c more common than isolated elevated
FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and
underestimate diabetes prevalence. Our prediction equations help allocate finite
resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and
surveillance.peer-reviewe
SUPERCRITICAL CARBON DIOXIDE EXTRACTION OF ESSENTIAL OIL FROM LIGNIFIED AQUILARIA SINENSIS
Aquilaria sinensis which is a highly valuable fragrant resinous wood possesses biological activities and pharmaceutical benefits. In this study, the essential oil from lignified ring and resin of Aquilaria sinensis were extracted using carbon dioxide under supercritical condition
Study on the Interfacial Curvature of Oil-Water Two Phase System subjected to Polymeric Additives
During the transportation of well fluids to refinery plant, drag which is also known as resistance will occur due to the friction between the pipelines and the fluids. Several pumping stations need to be installed along the pipelines due to the pressure drop which eventually increase the cost of transportation. Thereafter, Toms - a researcher in UK has discovered in 1949 that the injection of polymeric drag reducing additives (DRA) can increase the flow rate in the pipeline significantly which had bring a huge contribution to the flow assurance sector. The drag reducing agent which is the polymer solution has the ability to change the flow properties of the medium during the fluids transportation. It also altered the interfacial curvature of oil-water phases which causing the flow rate to be increased
Study on the Interfacial Curvature of Oil-Water Two Phase System subjected to Polymeric Additives
During the transportation of well fluids to refinery plant, drag which is also known as resistance will occur due to the friction between the pipelines and the fluids. Several pumping stations need to be installed along the pipelines due to the pressure drop which eventually increase the cost of transportation. Thereafter, Toms - a researcher in UK has discovered in 1949 that the injection of polymeric drag reducing additives (DRA) can increase the flow rate in the pipeline significantly which had bring a huge contribution to the flow assurance sector. The drag reducing agent which is the polymer solution has the ability to change the flow properties of the medium during the fluids transportation. It also altered the interfacial curvature of oil-water phases which causing the flow rate to be increased