A novel purification process for dodecanedioic acid by molecular distillation

A novel purification process is involved to obtain the high purity[>99%(by mass)]dodecanedioic acid(DC_(12)).It involves a re-crystallization followed by molecular distillation from the crude product.The objective of this study is to investigate general conditions,feed rate,distilling temperature and vacuum,necessary for centrifugal distillation of DC_(12).Under the optimum conditions,distilling temperature 180℃,pressure 30 Pa and feed flow rate700 ml·h^(-1),the purity of DC_(12) in the residence reached 97.55%with a yield of 53.18%by the analysis of gas chromatography.Multiple-pass distillation made a considerable contribution by improving the purity to99.22%.Additionally,the effect of pretreatment(re-crystallization) on distillation process was revealed through a series of comparative experiments.

Optimization of Wax Esters Production from Palm Fatty Acid Distillate and Oleyl Alcohol over Amberlyst 15

Wax esters were derived from long chain fatty acids and long chain alcohols with chain length of 12 carbons or more. These compounds have many potential applications in cosmetics, pharmaceuticals and food industries. The present work focuses on the synthesis of wax esters using palm fatty acid distillate and oleyl alcohol catalyzed by Amberlyst 15. Response surface methodology （RSM） based on a five-level, three-variable central composite design （CCD） was used to evaluate the interactive effects of synthesis, of amount of Amberlyst 15 catalyst （21.6-38.4% w/w）, reaction time （18-102 min） and molar ratio （palm fatty acid distillate to oleyl alcohol, 1：1.16-1：2.84） on the percentage conversion of palm fatty acid distillate. The optimum conditions derived via RSM were： amount of catalyst 33% w/w, reaction time 95 minute and palm fatty acid to oleyl alcohol molar ratio 1：2.7. The actual experimental conversion was 81.52% under optimum condition, which compared well to the maximum predicted value of 80.50%. Analysis of the yield showed that at optimum condition, 80.54% wax esters were produced.

Influences of operating conditions on biocatalytic activity and reusability of Novozym 435 for esterification of free fatty acids with short-chain alcohols:A case study of palm fatty acid distillate

In the present study, the effects of operating conditions on biocatalytic activity and stability of Novozym 435 for repeated-batch biodiesel production from free fatty acid （FFA） were investigated. Thermal deactivation caused by increased operating temperature from 45 to 50 ℃ could seriously affect the reusability of Novozym 435. The deactivation of Novozym 435 during the esterification of oleic acid with ethanol tended to be stronger than that in the system with methanol. Under the optimal conditions, considering both biocatalytic activity and stability of the enzyme, Novozym 435 could be reused for 13 cycles for biodiesel productions from oleic acid and absolute alcohols （methanol and ethanol） with FFA conversions of at least 90%. The presence of 4%-5% water in ethanol significantly affected the reusability of Novozym 435. Changes in the surface morphology of Novozym 435 during the esterification with various conditions were observed. It was revealed that the reduction in catalytic activity was related to the swelling degree of the catalyst surface, Additionally, biodiesel production from low cost renewable feedstocks, such as palm fatty acid distillate （PFAD） and 95% ethanol was examined, The esterification of PFAD with 95% ethanol catalyzed by Novozym 435 in 10-repeated batch operation showed the similar results in FFA conversion as compared to those using oleic acid. Novozym 435 remained active and could maintain 97.6% of its initial conversion after being used for 10 hatches.

Amino acid digestibility in low-fat distillers dried grains with solubles fed to growing pigs

The objective of this experiment was to determine the standardized ileal digestibility（SID） of amino acids（AA） in 3sources of distillers dried grains with solubles（DDGS） with different concentrations of fat.Twelve growing barrows（initial body weight：76.1 ± 6.2 kg） were randomly allotted to a replicated 6×4 Youden square design with 6 diets and 4 periods.The fat content of the 3 sources of DDGS were 11.5,7.5,and 6.9%respectively.Diets contained 60%DDGS and fat concentration of the diets were 7.5,52,and 5.2%,respectively.Two additional diets containing the 2sources of DDGS with 75 and 6.9%fat were also formulated,and corn oil was added to these diets to increase the concentration of fat in the diets to levels that were calculated to be similar to the diet containing conventional DDGS with 11.5%fat.A N-free diet was also formulated to calculate endogenous losses of crude protein（CP） and AA from the pigs.Pigs were fed experimental diets during four 7-d periods.The first 5 d of each period were an adaptation period and ileal digesta were collected on d 6 and 7 of each period.The apparent ileal digestibililty（AID） and SID of CP and all indispensable AA,except AID Pro and SID of Trp,were greater（P 〈 0.01） in conventional DDGS than in the 2 sources of DDGS with reduced fat.Adding oil to the diets containing the 2 sources of DDGS with reduced fat did not consistently increase SID of AA.In conclusion,conventional DDGS has greater SID values for most AA compared with DDGS that contains less fat and inclusion of additional oil to diets containing low-fat DDGS does not increase AID or SID of AA.The lower AA digestibility in low-fat DDGS could not be overcome by the inclusion of additional fat to the diets.

Optimizing Vitamin E Purification from Unsaponiable Matter of Palm Fatty Acids Distillate by Low Temperature Solvent Crystallization

Palm fatty acid distillate （PFAD）, a by-product of deodorization in palm oil refining, contains about 0.7%-1% vitamin E. The advantage of PFAD over other vitamin E sources is higher amount of tocotrienols than that of tocopherols. Vitamin E purification of unsaponiable matter of PFAD was aimed to remove other impurities to obtain high vitamin E concentration, mainly tocotrienols. This research used low temperature solvent crystallization to purify vitamin E. To optimize response of vitamin concentration, a response surface method was applied with three factors, i.e., the ratio between solvent and unsaponifiable matter （A）, crystallization temperature （B）, and crystallization time （C）. The relation of three factors was quadratic with equation Y = -128.54361 ＋ 41.33904A - 0.87995B ＋ 1.58941C ＋ 0.00290AB - 0.044324AC ＋ 0.00120BC - 3.33113A2 - 0.039535B2 - 0.02710C2. The optimum crystallization condition was obtained at ratio of solventto unsaponifiable matter of 6.04：1, crystallization temperature of-10.54 ℃, and crystallization time of 24.16 hours. Vitamin E enriched fraction from optimum crystallization conditions contained vitamin E of 20.13% （w/w）.

Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization

A palm fatty acid distillate （PFAD） has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst （SGAC） was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology （RSM）. The optimum reaction conditions were： 12.2：1 methanol-to- PFAD molar ratio, 2.9% catalyst concentration and 134 rain of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5% of the free fatty acid （FFA） conversion with 92.4% of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards.

ANALYSIS OF PETROLEUM ACIDS IN DUSHANZI DISTILLATE

A method which involves conversion of carboxylic acids to corresponding hydrocarbons and determination of high-resoiution mass spectrometry has been applied to the analysis of petroleum acids in Dushanzi distillate and resulted in compound class identification of petroleum acids which have not been reported previously in Xinjiang petroleum.

Improving cold flow properties of palm fatty acid distillate biodiesel through vacuum distillation

Palm fatty acid distillate(PFAD),a by-product of refining process of crude palm oil can be used as a potential feedstock for biodiesel production.However,the application of palm oil-based biodiesel is often hinder by its poor cold flow properties(CFP).Biodiesel fuel with poor CFP may crystallize and result in clogging of fuel lines,filters and injectors that cause engine operability problems.For that,a vacuum distillation method was designed and its feasibility and efficiency in improving the CFP was examined.A total of 13.60wt%of total saturated fatty acid methyl esters were successfully removed from the PFAD biodiesel,resulting in the improvement of the cloud point(CP),cold filter plugging point(CFPP)and pour point(PP)of PFAD biodiesel from 20℃,19℃,and 15℃to 13℃,11℃,and 9℃,respectively.It is remarkable that the improved CFPP satisfied the requirements for grade C summer biodiesel for temperate climates in EN 14212 standard.Additionally,Sarin(U FAME)empirical correlation was evaluated and it was found to have a good prediction of CFP for PFAD biodiesel,with lower than 2℃deviation.

Valorization of palm oil refining by-product for organotin mercaptide as a polyvinyl chloride thermal stabilizer:Synthesis,efficacy and comparison to mixed metal stearate

Organotin mercaptide-based thermal stabilizer is recognized for its effectiveness in enhanc-ing thermal stability of polyvinyl chloride(PVC).In this study,we synthesized an organotin mercaptide-based thermal stabilizer from palm fatty acid distillate,which is a by-product of palm oil refining process,and then evaluated its thermal stabilizing effects on PVC and compared its efficacy and economics to those of mixed metal stearate.The synthesized thermal stabilizer mani-fests as methyltin mercaptoethyl carboxylate sulfides.Both dehydrochlorination and two-roll mill discoloration tests have demonstrated the high efficacy of the resulting thermal stabilizer in stabi-lizing PVC,surpassing the performance of mixed metal stearate,as evidenced by the lower dosage required.The synthesized PVC thermal stabilizer not only provides effective stabilization but also presents a competitive viable alternative.

Influence of free fatty acid content and degree of fat saturation on production performance,nutrient digestibility,and intestinal morphology of laying hens

This study was conducted to evaluate the effects of dietary free fatty acid(FFA)content and degree of fat saturation on production performance,lipid and calcium digestibility,and intestinal function of laying hens.For a 15-week period,a total of 144 laying hens(19 weeks old)were randomly assigned to 8 dietary treatments,which were obtained by gradually replacing crude soybean oil with soybean acid oil(AO),or crude palm oil with palm fatty acid distillate(FAD).Thus,there were 4 soybean and 4 palm diets with 6%added fat varying in their FFA percentage(10%,20%,30%,and 45%),following a 2×4 factorial design.Each treatment included 6 replicates with 3 birds per replicate.Average daily feed intake and final body weight were significantly higher in palm diets(P<0.001),while no differences were found in egg mass and feed conversion ratio.Higher levels of FFA in soybean diets resulted in lower egg production and higher egg weight(linear,P<0.01).Regarding the degree of fat saturation,hens fed soybean diets presented higher digestibility of ether extract(EE),fatty acids,and calcium than palm diets(P<0.001).The dietary FFA percentage negatively affected the digestibility of EE and calcium(P<0.01),while having little effect on FA digestibility.There was a significant interaction in the AME;lower values were reported in soybean diets as the dietary FFA percentage increased(linear,P<0.01),whereas palm diets remained unaffected.The experimental diets had little effect on gastrointestinal weight and length.However,the jejunum of soybean diets showed higher villus height and higher villus height-to-crypt depth ratio than palm diets(P<0.05),and the dietary FFA percentage increased the crypt depth and decreased the villus height-to-crypt depth ratio(linear,P<0.05).It was concluded that varying dietary FFA content did not affect fat utilization as much as the degree of saturation did,supporting the use of AO and FAD as alternative fat ingredients.