Sequential solid phase extraction protocol followed by liquid chromatography–atmospheric pressure chemical ionization–mass spectrometry for the trace determination of non ionic polyethoxylated surfactants in tannery wastewaters

Automated solid-phase extraction (SPE) with C18 and styrene–divinylbenzene cartridges in series was used for the preconcentration of non ionic polyethoxylated surfactants in tannery wastewater. Fractionated extracts were analyzed by LC–MS using Atmospheric Pressure Chemical Ionization (APCl) in the Positive and Negative Ion modes. Recoveries for nonionic surfactants were approximately of 72, 90 and 80% for polyethylene glycols, nonylphenol and alcohol ethoxylates in the polar, aromatic and medium polarity fractions, respectively. Data acquisition in the selected ion monitoring mode afforded limits of quantification from 0.1 to 0.8 μg/l for tridecylic polyethoxylated alcohol and polyethoxylated glycol, respectively, in the complex tannery wastewaters. The tannery effluents investigated contained between 0.03 to 3.0 mg/l of polyethylene glycol and nonylphenol polyethoxylate, respectively. ©     

Recovery of Chromium(III) from Tannery Wastewater by Nanoparticles and Whiskers of Chitosan

Chitosan, its nanoparticles and whiskers present an excellent capacity to complex chromium ions. However, this phenomenon is influenced by different parameters. In our search, we determined the appropriate range of pH to form chitosan–Cr(III), nanoparticles Cr(III) and whiskers–Cr(III) complex. We studied also the influence of chromium concentration and nature of chitosan-based materials on complexation process. Our main aim is approximate the optimal conditions to remove chromium(III) from tanning bath, recuperated from tannery wastewater of Marrakech in Morocco. However, the results of adsorption kinetic in tannery wastewater revealed that chitosan, its nanoparticles, whiskers and biocomposites are good sorbent of chromium as well, even if the adsorbed quantity is less compared to chromium solution. Although, according to ICP-OES analysis in this real effluent, nanoparticles are the best complexing ligand, after 24 h of contact nanoparticles can remove 70% of chromium from this tannery wastewater.     

Waste glass as absorbent for thin layer chromatography (TLC)

This study shows that glass powder of 200–300 mesh size range can be used as an absorbent for thin layer chromatography without adding any binder provided its uniformity is improved by a suitable thermal treatment. For this purpose TLC plates of the said mesh size range glass powder are heated thermally in a muffle furnace at a temperature of 650 °C for a period of 3 h.     

New methodology for a selective on-line monitoring of some polar priority industrial chemicals in waste water

A new methodology is described for the development of on-line measurements of selected hazardous polar pollutants in waste water. The on-line automated system consists of a selective solid-phase extraction in order to isolate, concentrate and clean up industrial waste water in one step followed by liquid chromatography and diode array or mass spectrometry detection. The new solid-phase extraction sorbents involve antigen–antibody interactions. Due to the high affinity and high selectivity of these interactions, extraction and clean-up of aqueous complex matrices are achieved on the same step. Therefore, chromatograms present very clean base-lines which greatly improves the detection and quantification of very polar analytes. Identification of analytes is reinforced since immunoextraction is based on a molecular structural recognition. Class-selective immunosorbents have been developed for the selective trapping of several groups of analytes structurally related such as polyaromatic hydrocarbons, benzidine and congeners, nitroaniline and aromatic amines. Comparison is given with real samples showing that most polar analytes cannot be detected at low level using conventional non-selective solid-phase extraction sorbents. Examples are presented for the determination of the two- to three-ring polyaromatic hydrocarbons as well as of basic polar industrial chemicals such as nitroaromatics and aromatic amines which are included in the US EPA or EEC priority lists of pollutants to be monitored in industrial effluents. These on-line procedures increase the speed of analysis, improve analyte delectability and can be integrated into on-site monitoring devices. ©     

典型电脱盐废水预处理技术及其应用

针对原油电脱盐废水处理形势日益严峻的问题,介绍了电脱盐废水预处理技术的研究及应用进展,分析了电脱盐废水预处理技术的原理、特点及应用效果,总结了影响电脱盐废水特点的主要因素,指出改进原油开采技术、提高电脱盐装置的运行和管理水平可从源头上改善电脱盐废水水质,进一步开发和应用先进技术对控制电脱盐废水污染具有积极意义。     

Effect of different tannery sludge compost amendment rates on growth,biomass accumulation and yield responses of Capsicum plants

Composting has been recognized as one of the most cost effective and environmentally sound alternatives for organic wastes recycling from long and composted wastes have a potential to substitute inorganic fertilizers. We investigated the potential of composted tannery sludge for ornamental purposes and to examine the effects of two different composts and concentrations on ornamental Capsicum growth. The two composts were produced with tannery sludge and the composition of each compost was: compost₁ of tannery sludge (C₁TS) – tannery sludge + sugarcane straw and cattle manure mixed in the ratio 1:3:1 (v:v:v); compost₂ of tannery sludge (C₂TS) – tannery sludge + “carnauba” straw and cattle manure in the ratio 1:3:1 (v:v:v). Each compost was amended with soil at rates (% v:v) of 0%, 25%, 50%, 75% and 100% (designation hereafter as T₁–T₅, respectively). The number of leaves and fruits were counted, and the stem length was also measured. Chlorophyll content was recorded on three leaves of each harvested plant prior to harvest. Number of leaves and fruits, stem length, dry weight of shoot and roots did not vary significantly between the plants grown in two tannery composts. All the treatments with composted tannery sludge application (T₂–T₅) significantly increased the number of leaves and fruits, stem length and chlorophyll content compared with the control (T₁). The chlorophyll content was higher in plants growing in the C₁TS compared to C₂TS. The results of the present study further suggest that Capsicum may be a good option to be grown on composted tannery amended soil.     

Charge-based fractionation of oxyanion-forming metals and metalloids leached from recycled concrete aggregates of different degrees of carbonation: A comparison of laboratory and field leaching tests

The release and charge-based fractionation of As, Cr, Mo, Sb, Se and V were evaluated in leachates generated from recycled concrete aggregates (RCA) in a laboratory and at a field site. The leachates, covering the pH range 8.4-12.6, were generated from non-carbonated, and artificially and naturally carbonated crushed concrete samples. Comparison between the release of the elements from the non-carbonated and carbonated samples indicated higher solubility of the elements from the latter. The laboratory leaching tests also revealed that the solubility of the elements is low at the “natural pH” of the non-carbonated materials and show enhancement when the pH is decreased. The charge-based fractionation of the elements was determined by ion-exchange solid phase extraction (SPE); it was found that all the target elements predominantly existed as anions in both the laboratory and field leachates. The high fraction of the anionic species of the elements in the leachates from the carbonated RCA materials verified the enhanced solubility of the oxyanionic species of the elements as a result of carbonation. The concentrations of the elements in the leachates and SPE effluents were determined by inductively coupled plasma mass spectrometry (ICP-MS).     

工业含钒废水处理工艺的研究进展

针对大量企业采用传统提钒法制备钒产品产生的工业含钒废水的处理问题,综述了工业含钒废水处理工艺的研究进展,分别详述了沉淀法、溶剂萃取法、离子交换法、电解法、吸附法和生物法的处理工艺,并对比分析了它们的优势与不足。指出:工业含钒废水的处理既是环保的要求,又可实现有价资源的回收利用;在实际应用时,可依据工业含钒废水的p H选择相应的处理工艺及处理试剂。     

Production and Purification of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Degrading Enzyme from Streptomyces sp. AF-111

A poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) degrading bacterial strain designated as AF-111 was isolated from sewage sludge sample. The bacterium was identified by 16S rRNA gene sequencing. The results revealed that strain AF-111 showed 99 % similarity with Streptomyces althioticus strain NRRL B-3981 and designated as Streptomyces sp. strain AF-111. An extracellular PHBV depolymerase enzyme was produced under optimized conditions and purified through ammonium sulphate fractionation and column chromatography. The enzyme was purified to homogeneity, indicated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and molecular weight was found to be approximately 51 kDa. Effect of temperature, pH, metal ions and inhibitors on the PHBV depolymerase activity was determined. The enzyme was stable at wide range of temperature (35–55 °C) and pH (6–8). PHBV depolymerase was stable in the presence of different metal ions except iron and zinc which had inhibitory effect on depolymerase activity. Both ethylenediamine teteracetic acid and phenylmethyl sulphonyl fluoride strongly inhibited enzyme activity which indicates that this enzyme belongs to the serine hydrolase family like other polyhydroxyalkanoate depolymerases. The results show that a depolymerase from strain AF-111 can effectively degrade PHBV, therefore, it can be applied in the process of biochemical monomer recycling.     

Growth responses and metal accumulation capabilities of woody plants during the phytoremediation of tannery sludge

Five woody plants species (i.e. Terminalia arjuna, Prosopis juliflora, Populus alba, Eucalyptus tereticornis and Dendrocalamus strictus) were selected for phytoremediation and grow on tannery sludge dumps of Common Effluent Treatment Plant (CETP), Unnao (Uttar Pradesh), India. Concentration of toxic metals were observed high in the raw tannery sludge i.e. Fe-1667 > Cr-628 > Zn-592 > Pb-427 > Cu-354 > Mn-210 > Cd-125 > Ni-76 mg kg⁻¹ dw, respectively. Besides, physico-chemical properties of the raw sludge represented the toxic nature to human health and may pose numerous risks to local environment. The growth performances of woody plants were assessed in terms of various growth parameters such as height, diameter at breast height (DBH) and canopy area of plants. All the plant species have the capabilities to accumulate substantial amount of toxic metals in their tissues during the remediation. The ratio of accumulated metals in the plants were found in the order Fe > Cr > Mn > Pb > Zn > Cu > Cd > Ni and significant changes in physico-chemical parameters of tannery sludge were observed after treatment. All the woody plants indicated high bioconcentration factor for different metals in the order Fe > Cr > Mn > Ni > Cd > Pb > Zn > Cu. After one year of phytoremediation, the level of toxic metals were removed from tannery sludge up to Cr (70.22)%, Ni (59.21)%, Cd (58.4)%, Fe (49.75)%, Mn (30.95)%, Zn (22.80)%, Cu (20.46)% and Pb (14.05)%, respectively.     

A study of heavy metals and their fate in the composting of tannery sludge

Tannery waste is categorized as toxic and hazardous in Malaysia due to its high content of Cr (in excess of 500 mg/kg) and other heavy metals. Heavy metals, when in high enough concentrations, have the potential to be both phytotoxic and zootoxic. Heavy metals are found as contaminants in tannery sludge. This investigation aimed to identify the fate of chromium, cadmium, copper, lead, and zinc concentrations in tannery sludge throughout a 50-day composting cycle. The results of this study showed a general increase in the removal of Cr, Cd, Pb, and to a much smaller extent Zn and Cu, manifested by a decrease in their overall concentrations within the solid fraction of the final product (the decreases were likely the result of leaching). Furthermore, in using a sequential extraction method for sludge composting at different phases of treatment, a large proportion of the heavy metals were found to be associated to the residual fraction (70-80%) and fractions more resistant to extraction, X-NaOH, X-EDTA, X-HNO3 (12-29%). Less than 2% of the metals were bound to bioavailable fractions X-(KNO3+H2O).     

Soil contamination by halogenated polycyclic aromatic hydrocarbons from open burning of e-waste in Agbogbloshie (Accra,Ghana)

Detailed composition of chlorinated and brominated polycyclic aromatic hydrocarbons (Cl-PAHs and Br-PAHs) generated during informal recycling of e-waste and their toxic relevance are still poorly understood. This study investigated the occurrence of Cl-PAHs and Br-PAHs in surface soil samples from the Agbogbloshie e-waste recycling site (Accra, Ghana) using quantitative gas chromatography–mass spectrometry (GC–MS) and comprehensive two-dimensional GC–time-of-flight mass spectrometry (GC × GC–ToFMS) profiling. The results of GC–MS analysis showed elevated concentrations in open e-waste burning areas (160–220 and 19–46 ng/g dry weight for Cl- and Br-PAHs, respectively) with substantial contribution from unidentified compounds (respectively, more than 36 and 70%, based on the total areas of potential peaks). Cl- and Br-PAHs from e-waste burning had a distinctive composition dominated by ring–ring compounds. Several homologue groups not monitored with GC–MS were found using GC × GC–ToFMS: PAHs with up to 5Cl or 3Br, mixed halogenated PAHs and chlorinated methylPAHs. The dioxin-like toxic equivalents of the identified Cl-/Br-PAHs in soils, estimated from their in vitro AhR agonist potencies relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin, were much lower than the range reported for chlorinated and brominated dioxins. However, the toxicity of the unidentified halogenated PAHs remained unclear.     

三维电极法处理含钴、锰废水

采用三维电极法对工业精对苯二甲酸(PTA)装置产生的含钴、锰废水进行处理.通过与传统二维电极法的处理效果进行比较,论证了三维电极法脱除Co2+,Mn2+的优越性.探究了填料类型、极板间电压、粒子电极填充比(粒子电极质量(g)与废水体积(mL)的比)、极板间距等工艺参数对Co2+,Mn2+脱除率的影响.实验结果表明,适宜...     

Determination of organic compounds in landfill leachates treated by Fenton–Adsorption

The objective of this study was to identify the organic compounds removed from the leachate when treated with Fenton–Adsorption by gas chromatography coupled to mass spectrometry (GC–MS) in order to identify toxic compounds that could be harmful for the environment or human health.The physicochemical characterization of the raw leachate was carried out before and after the Fenton–Adsorption process. The effluent from each stage of this process was characterized: pH, Biological Oxygen Demand (BOD₅), Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), Total Carbon (TC), Inorganic Carbon (IC), Total Solids (TS), Total Suspended Solids (TSS) and Color. The organic compounds were determined by GC–MS.The removal of COD and color reached over 99% in compliance with the Mexican Standard NOM-001-SEMARNAT-1996, which establishes the maximum permissible limits for contaminants present in wastewater discharges to water and national goods. The chromatographic analysis from the Fenton–Adsorption effluent proved that this treatment removed more than 98% of the organic compounds present in the initial sample. The mono (2-ethylhexyl) ester 1,2-benzenedicarboxylic acid persisted, although it is not considered as toxic compound by the NOM-052-SEMARNAT-2005. Therefore, the treated effluent can be safely disposed of into the environment.     

Removal of Cinnamic Acid Derivatives from Aqueous Effluents by Fenton and Fenton-like Processes as an Alternative to Direct Biological Treatment

The removal of various phenolic acids (p-coumaric, caffeic and ferulic acids), typically found in wastewaters of agricultural origin, from model effluents by chemical and biological means has been investigated. Chemical oxidation processes comprising hydrogen peroxide and a homogeneous or heterogeneous copper or iron catalyst were employed over a wide range of experimental conditions. Chemical oxidation is capable of removing most of the total organic carbon initially present in the effluent at relatively mild treatment conditions (i.e. reaction times up to 120 min and temperatures up to 80°C), while removal rates generally increase with increasing temperature, H₂O₂ and catalyst concentrations. The anaerobic degradability and toxicity of p-coumaric acid has been assessed using the biochemical methane potential and anaerobic toxicity assay respectively. p-Coumaric acid, at concentrations below about 1 g/L, is not toxic against methanogens and slowly degrades over a period of about 35 days at 35°C. In light of this, chemical oxidation may provide a promising alternative to direct biological treatment for either the partial or complete removal of phenolic acids at reasonable treatment times; the implications for wastewater treatment are discussed.     

Substance Flow Analysis and Source Mapping of Chemical UV-filters

Chemical ultraviolet (UV)-filters are used in sunscreens to protect the skin from harmful UV radiation which may otherwise cause sunburns and skin cancer. Commonly used chemical UV-filters are known to cause endocrine disrupting effects in both aquatic and terrestrial animals as well as in human skin cells. Here, source mapping and substance flow analysis were applied to find the sources of six UV-filters (oxybenzone, avobenzone, 4-methylbenzylidene camphor, octyl methoxycinnamate, octyl dimethyl PABA and homosalate) and to identify the most dominant flows of these substances in Denmark. Urban water, composed of wastewater and surface waters, was found to be the primary recipient of UV-filters, whereby wastewater received an estimated 8.5–65 tonnes and surface waters received 7.1–51 tonnes in 2005. In wastewater treatment plants, their sorption onto sludge is perceived to be an important process and presence in effluents can be expected due to a lack of biodegradability. In addition, the use of UV-filters is expected to continue to increase significantly. Not all filters (e.g., octyl dimethyl PABA and homosalate) are used in Denmark. For example, 4-MBC is mainly associated with self-tanning liquids and private import of sunscreens.     

Characteristics of gas and residues produced from electric arc pyrolysis of waste lubricating oil

An attempted has been made to recover high-calorific fuel gas and useful carbonaceous residue by the electric arc pyrolysis of waste lubricating oil. The characteristics of gas and residues produced from electric arc pyrolysis of waste lubricating oil were investigated in this study. The produced gas was mainly composed of hydrogen (35–40%), acetylene (13–20%), ethylene (3–4%) and other hydrocarbons, whereas the concentration of CO was very low. Calorific values of gas ranged from 11,000 to 13,000 kcal kg^?1 and the concentrations of toxic gases, such as NO_x, HCl and HF, were below the regulatory emissions limit. Gas chromatography–mass spectrometry (GC/MS) analysis of liquid-phase residues showed that high molecular-weight hydrocarbons in waste lubricating oil were pyrolyzed into low molecular-weight hydrocarbons and hydrogen. Dehydrogenation was found to be the main pyrolysis mechanism due to the high reaction temperature induced by electric arc. The average particle size of soot as carbonaceous residue was about 10 μm. The carbon content and heavy metals in soot were above 60% and below 0.01 ppm, respectively. The utilization of soot as industrial material resources such as carbon black seems to be feasible after refining and grinding.     

高电压电容吸附法处理模拟含盐废水

针对电容吸附除盐法的缺点,通过对电极进行绝缘处理,开发了一种新型高电压电容吸附除盐技术。实验结果表明：增大外加电压,有利于除盐效率的提高;外加电压为60V时,NaCl去除率可达90%以上;增大废水流速对吸附效果不利;反应温度对处理效果的影响不大;在NaCl质量浓度为80mg/L、外加电压为60V、反应温度为25℃、废水流速为36m/s、反应时间为30min的条件下,经一级处理和二级处理后出水的NaCl质量浓度分别为39mg/L和16mg/L,NaCl去除率分别为51.3%和80.0%。     

萃取浓缩-薄涂柱气相色谱法测定煤焦油废水中的联苯和菲

用苯萃取浓缩煤焦油废水中的联苯和菲，然后用薄涂柱气相色谱法进行测定。试验表明：该法具有色谱柱温低、快速、准确等特点。     

Anaerobic co-digestion of tannery waste water and tannery solid waste using two-stage anaerobic sequencing batch reactor: focus on performances of methanogenic step

In this study, anaerobic co-digestion of the tannery waste water (TWW) and tannery solid waste (TSW) with four TWW to TSW mixing ratios (100:0, 75:25, 50:50 and 25:75) was carried out using semi-continuous two-phase anaerobic sequencing batch reactor system under mesophilic temperature (38?±?2 °C). During the experimental study, effluents resulted from previously optimized acidogenic reactors were used to feed subsequent methanogenic reactors and then operated at hydraulic retention time (HRT) of 20, 15 and 10 days and equivalent organic loading rate. The findings revealed that methanogenic reactor of 50:50 (TWW:TSW) treating the effluent from previously optimized acidogenic step exhibits best process performances in terms of daily biogas (415 ml/day), methane production (251 ml/day), methane content (60.5%) and COD removal efficiency (75%) when operated at HRT of 20 days. Process stability of methanogenic step also evaluated and the obtained results showed suitable pH (6.8), no VFA accumulation, i.e., VFA/Alkalinity (0.305), alkalinity (3210 mgCaCO₃/l) and ammonia (246 mg/l with in optimum operating range). In general, improved process stability as well as performance was achieved during anaerobic co-digestion of TWW with TSW compared to mono-digestion of TWW.