Determination of the carbonyl index of polyethylene and polypropylene using specified area under band methodology with ATR-FTIR spectroscopy

The current measurement techniques described in the literature for the determination of the carbonyl index (CI) for polyolefins such as polyethylene and polypropylene were compared and contrasted. These were all found to be inconsistent or inaccurate and were not capable of differentiating significant changes in carbonyl peak evolution throughout accelerated ageing. As a consequence of these findings, a methodology, specified area under band (SAUB) is presented here to more accurately represent the CI as a general means of reporting. The increased precision in the methodology is explained and compared to other methodologies for determining CI. The SAUB method is also shown to be capable of elucidating the differences in relative extent and rates of CI for different polyolefins, exposed to the same conditions over the same time period.

Fuel Analysis of Jatropha Methyl Ester and n-Tridecane as an Alternative Fuel for the Future

The authors proposed for new fuel between blending of jatropha methyl ester and n-tridecane. Biodiesel has an advantage in reducing emissions. Nevertheless, it has high viscosity and density and has poor spray characteristics compared to diesel fuel. The blending between n-tridecane would overcome the unwanted fuel properties. The n-tridecane and jatropha methyl ester were blended under three condition; JME25% (Jatropha Methyl Ester 25% and n-tridecane 75%), JME50% (Jatropha Methyl Ester 50% and n-tridecane 50%), and JME75% (Jatropha Methyl Ester 75% and n-tridecane 25%). The fuel properties were analyzed under biodiesel standardization from JIS K and ASTM D. FTIR analyzed also showed the characteristics of carbonyl peak that indicates as methyl ester. In the results, JME50% had met the requirements for fuel properties from biodiesel standardization.

Evaluation of in-situ transient simultaneous cell disruption and transesterification of microalgae

Microalgae has recently been highlighted as source of valuable products including biofuel. The production process of biofuels from microalgae involves mass cultivation, harvesting, deep dewatering, lipid extraction and biofuel conversion. In this work, lipids from microalgae Navicula sp. were obtained using multifunctional process that consists of acid hydrolysis or cellular disruption, oil extraction and in situ transesterification. The effect of alcohol added to produce ethyl and methyl esters on lipid extraction efficiency was evaluated using methanol and ethanol in order to determine the most suitable route for obtaining the high values of lipids and total reducing sugar. The highest lipid extraction efficiency and total reducing sugar (7.72 % and 2.63 mg/ml, respectively) was obtained for methanol. The low lipid extraction efficiency of multifuctional process is due to transesterification of lipids that gradually released into the system. The formation of alkyl esters was confirmed by FTIR with an increase in carbonyl peak as the reaction progressed, thus muntifuctional process reduce cost of alkyl esters production by eliminating the step of lipid extraction by solvent.

Synergistic Antioxidation Properties of Tin Dialkyldithiocarbamate With Dialkyldiphenylalmine

Differential scanning calorimetry (DSC) and thin film micro oxidation test (TMOT) were employed to evaluate the antioxidation properties of tin dialkyldithiocarbamate (SnDDC) with p,p′dioctyldiphenylamine (DODPA) antioxidant in pentaerythritol ester (PE) or polyalphaolefin synthetic lubricant (PAO), and their chemical structure were identified by fourier transform infrared spectroscopy (FTIR) analysis. DSC test shows that incipient oxidation temperature and oxidation induction time of DODPA-containing PE were improved significantly by SnDDC addition, SnDDC shows a good oxidative synergism with DODPA antioxidant. TMOT results indicates that the combination of SnDDC and DODPA in polyalphaolefin can also effectively reduce the weight lost, carbonyl peak square index and diposits of oxidized oils, which confirm that the combination of SnDDC and DODPA exhibit good synergistic antioxidation properties and deposits inhibition.