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1.
Summary Two types of fatty industrial wastewaters, wool scouring effluents (WSE) and olive oil mill effluents (OME) were analysed (lipids, phenols and COD), and were then treated anaerobically in laboratory-scale fixed bed filters. Approximately 50% of the organic compounds in both wastewaters was degraded at two days of hydraulic residence time. A higher biogas production was obtained when using OME rather than WSE. This experimental study confirmed that anaerobic digestion can be considered as a roughing treatment in a multi-step process for industrial fatty wastewaters.  相似文献   

2.
In this article, the phenolic composition of wastewaters prepared from different cultivars of Olea europaea have been described. The main aim is the recovery of these compounds for technological utilization.  相似文献   

3.
The anaerobic biodegradability and toxicity of olive mill waste-waters (OMW) were studied in batch anaerobic digestion experiments. Anaerobic digestion of OMW or the supernatant of its centrifugation, the methane production was achieved at up to 5–15% (V/V) dilution corresponding to only 5–20 g/L COD. The washed suspended solids of OMW were toxic at up to 80 g/L COD; however, the kinetic of biodegradability of OMW or the supernatant was faster than for suspended solids, which are constituted meanly of cellulose and lignin. The darkly colored polyphenols induce the problem of biodegradation of OMW, whereas the long chain fatty acids (LCFA), tannins and simple phenolic compounds are responsible its toxicity for methanogenic bacteria.  相似文献   

4.
The possibility of oxidizing at a PbO2 anode the phenols and polyphenols, present in the olive oil mill wastewater, has been studied as a pretreatment for the submission of such wastewater to the traditional biological treatments. The results obtained operating at current densities ranging 500 to 2000 A/m2 show that it is possible to reduce the concentration of the phenolic components, which interfere with the biological treatments, down to low values without decreasing too much the total organic content of the wastewater.  相似文献   

5.
A new secoiridoid, olenoside A (1a) and its known epimer olenoside B (1b), were isolated from olive mill wastewater as a mixture of two isomers. Their structures, 1-methyl-7-oxo-6,6a,8,8a-tetrahydro-1H,3H-pyrano[3,4-c]pyran-4-carboxylic acid methyl ester, were determined by spectroscopic methods including 2-D NMR. The structure of major compound 1a was confirmed by X-ray diffraction.  相似文献   

6.
7.
Olive oil mill wastewater (OMWW) is very rich in phenolic compounds especially the key compounds of caffeic acid (CA), hydroxytyrosol (HTY), and tyrosol (TY). Therefore, the development of new and effective analytical and industrial methods for the separation and concentration of these valuable compounds has attracted great attention in the last decades. In this study, a selective transport and separation method for CA, HTY, and TY from OMWW samples, obtained from different olive orchards, using a new bulk liquid membrane (BLM) procedure was developed. Various factors influencing the transport efficiency such as pH of the source and receiving phases, nature and volume of the organic membrane, stirring rate, and transport time were investigated and optimized. Under optimal experimental conditions, the transport efficiencies of CA, HTY, and TY from the OMWW samples of 90.1 %, 28.4 %, and 34.9 % were obtained, respectively. Relative standard deviations (RSDs, n = 7) were found to be 4.1 %, 3.8 %, and 3.0 % and the limits of detection (LODs) obtained were 0.001 mg L?1, 0.011 mg L?1, and 0.008 mg L?1, for CA, HTY, and TY, respectively.  相似文献   

8.
The solid fraction of olive mill waste water (OMWW) was separated from OMWW and then the solutes in the solid fraction of OMWW were extracted with ethanol. The detection of polyphenols in the ethanol extract showed the presence of polyphenols in the solid fraction of OMWW. Effects of solvent-to-solid ratio, extraction and agitation time on the extraction of polyphenols from the solid fraction of OMWW were examined and the maximum amount of polyphenol was extracted from the solid fraction of OMWW with a solvent-to-solid ratio of 15 at 70?min of extraction and 10?min of agitation time. Percent yields and purities of the polyphenols extracted from solid fraction of OMWW were higher than those of the polyphenols extracted from olive pomace with ethanol at 70?min of extraction and 10?min of agitation time with solvent-to-solid ratio of 15.  相似文献   

9.
Bismurrangatin and murramarin A, two new coumarins, were isolated from the vegetative branches of Murraya exotica. Murramarin A is a rare type of bicoumarin that connects two coumarin moieties by orthoester structure. The structures were elucidated based on spectroscopic methods, especially by 2D-NMR experiments.  相似文献   

10.
Biodiesel (fatty acid methyl esters) was produced by transesterification of triglycerides (triolein) present in olive oil with methanol and Novozym435. The effect of the molar ratio of methanol to triolein, semibatch (stepwise addition of methanol) vs batch operation, enzyme activity, and reaction temperature on overall conversion was determined. Stepwise methanolysis with a 3:1 methanol to triolein molar ratio and an overall ratio of 8:1 gave the best results. The final conversion and yield of biodiesel were unaffected by initial enzyme concentrations greater than 500 U/mL olive oil. The optimum reaction temperature was 60 degrees C. Comparison of conversion data between a test-tube scale reactor and a 2-L batch reactor revealed that the difference in conversion was within 10%. Experiments were also carried out with used cooking oil; the conversion with used cooking oil was slightly lower but no major differences were observed. The efficacy of Novozym435 was determined by reusing the enzyme; although the enzyme's relative activity decreased with reuse, it still retained 95% of its activity after five batches and more than 70% after as many as eight batches.  相似文献   

11.
The recent implementation of a new two-step centrifugation process for extracting olive oil in Spain has substantially reduced water consumption, thereby eliminating oil mill wastewater. However, a new high sugar content residue is still generated. In this work the two fractions present in the residue (olive pulp and fragm ented stones) were assayed as substrate for ethanol production by the simultaneous saccharification and fermentation (SSF) process. Pretreatment of fragmented olive stones by sulfuric acid-catalyzed steam explosion was the most effective treatment for increasing enzymatic digestibility; however, a pretreatment step was not necessary to bioconvert the olive pulp into ethanol. Theolive pulp and fragmented olive stones were tested by the SSF process using a fed-batch procedure. By adding the pulp three times at 24-h intervals, 76% of the theoretical SSF yield was obtained. Experiments with fed-batch pretreated olive stones provided SSF yields significantly lower than those obtained at standard SSF procedure. The preferred SSF conditions to obtain ethanol from olives stones (61% of theoretical yield) were 10% substrate and addition of cellulases at 15 filter paper units/g of substrate.  相似文献   

12.
蒋万枫  张宁  张凤艳  杨钊 《色谱》2017,35(7):760-765
建立了测定橄榄调和油中橄榄油含量的顶空气相色谱-质谱分析方法。对样品量、加热温度、加热时间、进样量、进样模式、色谱柱进行了优化。通过化学计量学方法发现了橄榄油的特征化合物。取1.0 g样品放置于20 m L顶空瓶中,在180℃加热振摇2 700 s,取1.0 m L顶空气体进样,通过HP-88色谱柱分离和质谱检测。结果表明,方法的线性范围为0~100%(橄榄油含量),线性相关系数(r2)大于0.995,检出限为1.26%~2.13%,模拟橄榄调和油中橄榄油含量测定的偏差为-0.65%~1.02%,相对偏差为-1.3%~6.8%,相对标准偏差为1.18%~4.26%(n=6)。该方法不使用任何溶剂,操作简单、快速、环保,灵敏度和准确度高,适用于橄榄调和油中橄榄油含量的测定。  相似文献   

13.
1,1-联二萘酚(B INOL)自1926年合成以来[1],因其独特的结构特点及强的立体控制能力,被广泛地应用于不对称合成中,其衍生物的合成也越来越受到人们的关注。目前,对联二萘酚母体环的修饰主要集中在3,3位碳上的取代。联二萘酚3,3位和6,6位碳上的取代。联二萘酚3,3位碳上的取代基通  相似文献   

14.
Huang SX  Xiao WL  Li LM  Li SH  Zhou Y  Ding LS  Lou LG  Sun HD 《Organic letters》2006,8(6):1157-1160
[reaction: see text] A phytochemical study of the secondary metabolites produced by the species of Isodon rubescens has led to the isolation of three new dimeric ent-kauranoids and two known ones. The most important of these compounds are bisrubescensin A (1), which contains an unprecedented C(23) ent-kaurane unit, and bisrubescensin C (3), which is the precursor of bisrubescensin B (2) from the viewpoint of biosynthesis. Their structures were determined on the basis of extensive spectroscopic analysis and chemical evidence.  相似文献   

15.
16.
The olive pulp fraction contained in the residue generated in olive oil extraction by a two-step centrifugation process can be upgraded by using the cellulose fraction to produce ethanol and recovering high value phenols (tyrosol and hydroxytyrosol). Olive pulp was pretreated in a laboratory scale stirred autoclave at different temperatures (150–250°C). Pretreatment was evaluated regarding cellulose recovery, enzymatic hydrolysis effectiveness ethanol production by a simultaneous saccharification and fermentation process (SSF), and phenols recovery in the filtrate. The pretreatment of olive pulp using water at temperatures between 200°C and 250°C enhanced enzymatic hydrolysis. Maximum ethanol production (11.9 g/L) was obtained after pretreating pulp at 210°C in a SSF fed-batch procedure. Maximum hydroxytyrosol recovery was obtained in the liquid fraction when pretreated at 230°C.  相似文献   

17.
Using caffeic acid and p-hydroxybenzoic acid as templates, two molecularly imprinted polymers (MIPs) were prepared that were used for isolation of polyphenols from olive mill waste water samples (OMWWs) without previous pre-treatment. For the preparation of the caffeic acid MIPs 4-vinylpyridine, allylurea, allylaniline and methacrylic acid were tested as functional monomers, ethylene glycol dimethylacrylate (EDMA), pentaerythritol trimethylacrylate (PETRA) and divinylbenzene 80 (DVB80) as cross-linkers and tetrahydrofuran as porogen. For p-hydroxybenzoic acid 4-vinylpyridine, allylurea and allylaniline were tested as functional monomers, EDMA and PETRA as cross-linkers and acetonitrile as porogen. The performance of the synthesized polymers was evaluated against seven structurally related compounds by means of polymer-based HPLC. The two polymers that presented the most interesting properties were further evaluated by batch rebinding and from the derived isotherms their capacity and binding strength were determined. Using solid-phase extraction (SPE), their ability to recognize and bind the template molecule from an aqueous solution as well as the pH dependence of the binding strength were explored. After establishing the best SPE protocol, an aqueous model mixture of compounds and a raw OMWWs sample were loaded on the two best polymers. The result of the consecutive use of the two polymers on the same sample was explored. It was concluded that acidic conditions favour the recognition abilities of both polymers and that they can be used for a quick and efficient isolation of the polyphenol fraction directly from raw OMWW.  相似文献   

18.

Background

Olive biophenols are emerging as a valued class of natural products finding practical application in the food, pharmaceutical, beverage, cosmetic and nutraceutical industries due to their powerful biological activity which includes antioxidant and antimicrobial properties. Olive mill waste water (OMWW), a by-product in olive oil manufacturing, is rich in biophenols such as hydroxytyrosol and tyrosol. The amount of biophenols depends on the cultivar, the geographical area of cultivation, and the seasonal conditions. The goal of this study was to develop a straightforward method to assess the economic value of OMWW via quantification of hydroxytyrosol and tyrosol.

Results

The amount of hydroxytyrosol and tyrosol phenolic compounds in the OMWW from four different cultivars grown in four different regions of Sicily was analyzed using liquid–liquid and solid–liquid analytical protocols developed ad hoc. Results showed significant differences amongst the different cultivars and their geographical origin. In all samples, the concentration of hydroxytyrosol was generally from 2 to 10 times higher than that of tyrosol. In general, the liquid–liquid extraction protocol gave higher amounts of extracted biophenols. The cultivar Cerasuola had the highest amount of both hydroxytyrosol and tyrosol. The cultivar Nocellara Etnea had the lowest content of both biophenols.

Conclusions

A quick method to assess the economic value of olive mill waste water via quantification of hydroxytyrosol and tyrosol in olive phenolic enriched extracts is now available.
  相似文献   

19.
The interest on energy recovery from renewable sources is increasing due to the global warming and fossil fuels limitation. Biomass thermochemical conversion methods present some significant advantages such as zero net emissions and the use of agricultural by-products. In this work, a study of the catalytic and non-catalytic pyrolysis of an exhausted olive waste was carried out. The objective was to characterize the solid, liquid and gaseous phases in terms of their energy content. Two experimental series were conducted: uncatalyzed processes, studying the influence of temperature in the range 400–900 °C; and catalyzed ones, investigating the influence of temperature (500–800 °C) and quantity of catalyst (0–100 g). Also, the dolomite effectiveness as catalyst was evaluated. For this motive, consecutive experiments, without reactivating dolomite, were carried out (0–6 runs), and the yields of solids, liquids and gases were determined. It was found that increasing temperature leads in both series to a decrease in the solid and liquid yields and to an increase in the gas yield. The presence and amount of catalyst caused a significant decrease in the liquid phase yield and a high increase in the gas phase yield giving rise to a vast rise in hydrogen production. On the other hand, the catalyst proved to be stable and did not lose activity during at least six pyrolysis cycles.Finally, as a previous step to the design of industrial installations, a kinetic study of the process was performed, based on the generation of the principal gases, considering that these are formed through parallel independent first-order reactions, with different activation energy.  相似文献   

20.
This paper describes the decolorization and chemical oxygen demand (COD) removal of olive mill waste-waters (OMW) byPhanerochaete chrysosporium grown in agitated submerged cultures. WhenP. chrysosporium was cultivated in the form of pellet, no decolorization of crude OMW was observed. Decolorization occured only after removing by ultrafiltration, the high-mol-wt (HM) polyphenolic fraction (> 60 kDa). The use of high lignin peroxidase (LiP) producing medium yielded the highest levels of OMW decolorization and COD removal. In this case, extensive depolymerization and subsequent accumulation of phenolics with intermediates molecular weight were observed. Furthermore, increasing the concentration of the HM fraction decreased the color and COD removals. The decolorizing activity was lost when the concentration of the HM fraction reached 25% (v/v). Consequently, LiP activity was found to be completely inhibited in the presence of HM fraction, but not with the low-mol-wt (LM) polyphenolic fraction (<8 kDa). The use ofP. chrysosporium immobilized on polyurethane foam resulted in efficient decolorization of crude OMW. Moreover, the addition of an induction medium was shown to perform several repeated batch cultures for OMW decolorization and COD removal.  相似文献   

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