Estrogen equivalent concentration of 13 branched para-nonylphenols in three technical mixtures by isomer-specific determination using their synthetic standards in SIM mode with GC-MS and two new diasteromeric isomers

Thirteen isomers of branched para-nonylphenols (para-NP) in three technical mixtures were isomer-specifically determined using their synthesized standards by SIM of structurally specific ions, m/z 135, 149 or 163 with GC–MS. Of the 13 isomers, four isomers, 4-(2,4-dimethylheptan-4-yl)phenol, 4-(4-methyloctan-4-yl)phenol, 4-(3-ethyl-2-methylhexan-2-yl)phenol (3E22NP) and 4-(2,3-dimethylheptan-2-yl)phenol synthesized for their determinations were first used as standard substances. The 13 isomers in the technical mixtures individually occurred at mass percent portion of more than 2%. The total mass percent portions in the mixtures from Tokyo Chemical Industry (TCI), Aldrich, and Fluka covered with 89 ± 2%, 75 ± 4% and 77 ± 2%, respectively. The abundance of 4-(3,6-dimethylheptan-3-yl)phenol in the three mixtures was the largest with 11.1 ± 2% to 9.9 ± 0.3%, while that of 4-(2-methyloctan-2-yl)phenol was the smallest with 2.9 ± 0.3% to 3.0 ± 0.2%. Additionally, structures of four new isomers of more than 1% portion present in a technical mixture were elucidated as two pairs of diastereomeric isomers: two types of 4-(3,4-dimethylheptan-4-yl)phenol (344NP) and those of 4-(3,4-dimethylheptan-3-yl)phenol (343NP). By estrogenic assay of 13 isomers with yeast estrogen screen system, the activity of 3E22NP was the highest, while that of 4-(3-methyloctan-3-yl)phenol was the least. Their relative activities to that of 3E22NP were individually calculated. Estrogenic equivalent concentrations of the three technical mixtures were predictively evaluated. The ratio of the EEC to the conventional concentration, total mass percent portions of the 13 isomers in technical mixtures were 0.208 for TCI, 0.206 for Aldrich and 0.205 for Fluka. The predicted estrogenic activity of measured concentration of para-NP in technical mixtures was approximately 5-fold greater than the measured estrogen agonist activity.     

Separation, synthesis and estrogenic activity of 4-nonylphenols: two sets of new diastereomeric isomers in a commercial mixture

Two sets of new diastereomeric 4-nonylphenol (NP) isomers [4-(3,4-dimethylheptan-4-yl)phenol (344NP, NP-J, L) and 4-(3,4-dimethylheptan-3-yl)phenol (343NP, NP-K, P)] were separated from a commercial NP mixture. The mixture of these diastereomers was synthesized at the same time by a single Friedel-Crafts reaction of 3,4-dimethyl-4-heptanol and phenol, and the mixture was separated into individual NPs by HPLC equipped with Hypercarb column. For the first time, in this study the stereostructure-estrogenic activity relationship of NP diastereomers was investigated. The NP isomers (NP-L and NP-P) having the beta-methyl group over the benzene ring were found to be 2-4 times more estrogenic than their diastereomers (NP-J and NP-K). In the case of the other set of diastereomer [4-(3,5-dimethylheptan-3-yl)phenol, (353NP, NP-E, G)] containing gamma-methyl group in the molecule, the gamma-methyl proton signal (delta 0.49) in the more estrogenic isomer (NP-G) also appeared in a higher field than the corresponding methyl signal (delta 0.76) of the less estrogenic isomer (NP-E).     

Simultaneous treatment of PVC and oyster-shell wastes by mechanochemical means

This work presents a new process for dechlorinating poly-vinyl chloride (PVC) by the use of oyster-shell waste. The process consists of milling of PVC waste with oyster-shell waste, followed by washing the milled sample with water. The milling of PVC and oyster-shell mixture results in size reduction and rupture in bonds, leading to mechanically induced reactions between the two to form CaCl2 and hydrocarbon with C=C bonds. Washing the milled mixtures with water at room temperature allows complete removal of chlorine from the milled sample. More than 95% of chlorine in PVC was removed when 2h grinding is conducted for the mixture. The present process could offer a potential route to the handling and disposal of oyster-shell and PVC wastes.     

Co-combustion of dried sewage sludge and coal in a pulverized coal boiler

More than 1.1 million tons of municipal and industrial sewage sludge is produced annually in Poland. Most of this sewage sludge is landfilled or used for recultivation and fertilization of soil. After accession of Poland to the EU, large investments are planned for wastewater treatment, so it is expected that the amount of sewage sludge produced in Poland will grow in the near future. It is well known that the combustion of sewage sludge is becoming a more and more popular utilization method of such waste. Unfortunately, the current situation in Poland makes it impossible to incinerate the sewage sludge because of a lack of incinerators. One possible solution for Poland is the co-firing of dried sewage sludge in existing coal-fired utility boilers. This article presents results of initial Polish industrial trials of dried municipal sewage sludge and hard coal co-combustion in an OP-230 pulverized coal boiler. Such a solution was shown to be technically viable and not to require changes to the existing technological system. Cocombustion of sewage sludge with coal in power plants seems to be the best solution for sludge utilization in the near future in Poland.     

Combustion characteristics of Malaysian municipal solid waste and predictions of air flow in a rotary kiln incinerator

Malaysia is in dire need of alternatives to landfilling for solid waste management. Recently, landfills have faced the problems of overfilling, overflowing of leachates leading to pollution of water resources, and uncontrolled dust emissions adversely affecting the local environment. With the rising cost of urbanization coupled with the high rate of waste generation, one possible method of waste treatment that is receiving particular attention by the government is incineration. Incineration of solid waste is rather new in Malaysia, with limited usage in handling small sources of waste generation such as the municipal solid waste (MSW) of resort islands; however, its potential in ameliorating the problems associated with solid waste treatment may make it an attractive alternative to landfill. This article presents the results of test runs conducted to investigate the performance of a locally designed and manufactured rotary kiln incinerator (RKI). The test runs were conducted using MSW collected from the Shah Alam municipality. The combustion efficiency was analyzed by looking at the temperature profiles and chemical species concentrations. To complement the combustion characteristics measurements, predictions of the air flow in the incinerator during the process were also investigated. The overall performance of the RKI suggests that it is suitable for treating MSW.     

Enhancement of turbulent scalar mixing and its application by a multihole nozzle in selective catalytic reduction of NOx

The mixing characteristics of a passive scalar in the turbulent flow of a selective catalytic reduction process were numerically and experimentally investigated, focusing especially on an injection nozzle with multiple holes for the reducing agent. The multihole injection nozzle studied has six holes that are perpendicular to the ambient flue gas flow and are located near the tip of the nozzle. Large eddy simulation was applied to the turbulent flow and mixing fields to elucidate the mixing mechanism of the proposed nozzle compared with the single-hole nozzle that is commonly used in the conventional selective catalytic reduction process. From the results, there exist broader regions of higher turbulent intensities for the multihole nozzle than for the conventional single-hole nozzle. These regions are well matched with the positions of high vorticity in the near upstream region of the jet flow issuing from the multiple holes of the nozzle. Consequently, the high turbulent intensities and vorticity magnitudes lead to intensified mixing between the flue gas and the reducing agent. Hence, the most suitable molar ratio between NOx and the reducing agent for the catalytic reaction can be easily obtained within a shorter physical mixing length as a result of the enhanced scalar mixing. Finally, the numerical results were applied to a trial design version of a multihole nozzle, and this nozzle was experimentally tested to confirm its mixing performance.     

Leaching behavior of heavy metals from municipal solid waste incineration bottom ash and its geochemical modeling

With the increase in the number of municipal solid waste incineration (MSWI) plants constructed in China recently, great attention has been paid to the heavy metal leaching toxicity of MSWI residues. In this study, the effects of various parameters, including extractant, leaching time, liquid-to-solid ratio, leachate pH, and heavy metal content, on the release properties of Cd, Cr, Cu, Ni, Pb, and Zn from MSWI bottom ash were investigated. Partial least-squares analysis was employed to highlight the interrelationships between the factors and response variables. Both experimental research and geochemical modeling using Visual MINTEQ software were conducted to study the pH-dependent leaching behavior of these metals in fresh and weathered bottom ash, considering precipitation/dissolution and surface complexation reactions (adsorption by hydrous ferric oxide and amorphous aluminum oxide/hydroxide). The results showed that leachate pH was the predominant factor influencing heavy metal leachability. The leaching of Cu, Pb, and Zn was mainly controlled by precipitation/dissolution reactions, whereas surface complexation had some effect on the leaching of Cr, Cd, and Ni for certain pH ranges. The modeling results aggreed well with the experimental results. Part of this work was presented at the Fourth International Conference on Combustion, Incineration/Pyrolysis and Emission Control (i-CIPEC)     

Influence of Technological Process on Biodegradation of PVA/Waxy Starch Blends in an Aerobic and Anaerobic Environment

Improving biodegradability of PVA/starch blends is a reality already documented by a number of works. Admittedly, mechanical properties of products (for example, tensile strength) are somewhat worse, but suitable composition optimizing or chemical modifying of starch may eliminate the problem to a large degree. This work is an attempt to find another potential effect influencing biodegradability, that of technological procedure for producing films from these blends on an extruder. The procedure with a so-called pre-extrusion step (two-stage) and dry-blend (single-stage) produced blends of slightest differences in achieved biodegradability (virtually within limits of experimental error) in aerobic (76 vs. 79%) as well as anaerobic breakdown (48 vs. 52%). Conversely, morphological analysis exhibited superior homogeneity of films prepared by the two-stage process; their tensile strength was also higher.     

Initial Changes in Refilled Lysimeters Built with Metal Polluted Topsoil and Acidic or Calcareous Subsoils as Indicated by Changes in Drainage Water Composition

Soil translocation for recultivation of soil removed from construction sites and for the preparation of refilled lysimeters inevitably involves disturbance of soil structure, and, if intermediate storage is included, also drying and rewetting of the soil. We report on an experiment with model forest ecosystems, where uncontaminated forest subsoils were covered with non-contaminated or freshly heavy metal (mainly Zn and Cu) contaminated topsoil in large lysimeters. Monitoring of the chemical composition of the drainage water revealed two distinct soil conditioning phases. During an initial phase of about a year strongly elevated nitrate and sulfate concentrations occurred that were attributed to a mineralisation flush caused by the increased accessability of mineralisable nitrogen and sulfur in destroyed aggregates. These effects were significantly larger in lysimeters with calcareous subsoil than in those with acidic subsoil. The second phase was characterised by a gradual decrease in dissolved organic carbon and sulfate concentrations, in particular in the acidic subsoil. This decrease may be attributed to the depletion of pools made accessible during aggregate destruction or the formation of new aggregates. These chemical changes had only little effects on the concentrations of copper and zinc in the drainage water. Based on our results, it can be concluded that large refilled lysimeters can be used for many purposes without risk of compromised results, if a conditioning phase of about 1 year with sufficiently moist soil conditions is respected. Nevertheless, gradual changes in soil chemical characteristics still occur after this initial phase. Implications for the recultivation of sites using relocated soils are discussed.