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A continuous population and industrialization growth have enhanced the production of chemical compounds as well as their structural chemical diversification. Unfortunately, they have become an increasing burden for the environmental sustainability and biodiversity. The need for producing and using environmentally friendly products become increasingly evident in the current context of environmental concerns. It is crucial to develop new products and technologies that reduce their overall harmful environmental impact and promote its sustainability. In this study, the citrus peels waste was transformed into a potential antibacterial and antifungal extract by hydrodistillation. The efficacy of orange peels hydro distillation process in obtaining plant extracts was improved by a pre-enzyme-assisted extraction step. Enzymes such as cellulase and pectinase improved the breakdown of cellulose and pectin structures, which led to an increased extraction yield of bioactive compounds and antimicrobial activity.

This paper presents the remediation of polluted soils with chlorinated pesticides (HCH, DDX) by zerovalent iron technology (ZVI). We performed soil remediation tests with iron (two grinding sizes), three doses, with iron and acetic acid (two doses for each dose of iron and for each type of grinding iron size). In the study was applied 99 tests (samples). The diminishing of HCH and DDX concentrations in treated samples is more significant with the increasing of iron and acetic acid doses, for the same contact time: 99% HCH and 91% DDX for large iron particles and 95% HCH and 82% DDX for small iron particles.

The municipal wastewater treatment is the source of significant amounts of primary and secondary sludge which is under the present legislation referring to quality and management aspects. It is estimated that a half of wastewater treatment plant costs are due to the sludge management. Anaerobically sludge stabilization, capitalization as energy source, in order to diminish the costs and sludge volume decreasing, are the aims of the main operational steps of sludge treatment, as a part of wastewater treatment plant. The improvement of sludge anaerobically stabilization process must be possible by acting in the rate limiting step - hydrolysis in order to rise the organic carbon solubilization. The increase of soluble carbon can be possible by adding a pretreatment step of waste biological sludge, ultrasonic disintegration being one option. This paper emphasized the experimental results regarding anaerobically stabilization of the thickened waste biological sludge by ultrasonication taking into account the results of blank test, without ultrasonication. Experimental tests show that ultrasonic disintegration of the sludge having initial dried substances content (dry weight) 2.72% and soluble organic load COD of 598 mg O2/L led to soluble COD concentration of 4950-6710 mg O2/L after sonication with specific energy in the range of 3.06 - 14.24 kWh/kg dry weight. Anaerobically stabilization during 25 test days at 36 0C of the mixture 40% disintegrated biological sludge and 60% digested sludge (inoculum) mixture led to 30-38.6% increase of biogas production comparing with parallel test with non-sonicated sludge.

Synthetic solutions of flutamide were subject to degradation using three advanced oxidation systems, namely UV/TiO2, UV/H2O2 and UV/H2O2/TiO2. Optimum conditions and degradation kinetics has been established for all three systems. The experimental results showed that all three systems can be successfully used for flutamide degradation with efficiencies higher than 99% and that advanced oxidation processes are showing good potential for degradation of organic pollutants that cannot be suitable removed/degraded using conventional wastewater treatment processes

New research applications involving the use of cellulosic material derived from maize stalk for on-site treatment of leachate were evaluated for specific removal of Cu(II) and Fe(III) from real, highly polluted tailing pond and mine wastewater samples. Two major issues generated by anthropic mining activities were also tackled: wastewater metal content decrease to improve water quality and subsequently metal specific recovery, increasing the economic efficiency of metal production by using a green technology for residual management. Rapid saturation of the maize stalk mass determined in batch studies and the mine pilot experiment led to diminished metal concentrations in the second pilot experiment, where Cu(II) and Pb(II) from synthetic solutions were monitored in order to test biomaterial performances. In addition, in the second pilot experiment, maize stalk removed Pb(II) in the first 36 h, below the determination limit of the analytical method. The biomaterial bed in the column was saturated after 252 h of inflow solution. FTIR-ATR, TG and SEM techniques probed the interaction between maize stalk polar groups C=O, –OH, C–O and tailing water metallic ions by large FTIR band displacements, intensity decrease and shape changes, modification of thermal stability and by changes in the appearance of adsorbent microstructure images owing mainly to ion exchange mechanism.

Understanding the volatile flavor compounds present in commercial beverages is crucial for the food and beverage industries as these compounds significantly influence product perception and consumer acceptability. This paper aims to comprehensively analyze the composition of volatile organic compounds in various commercial beverages using targeted gas chromatographic–mass spectrometry (GC/MS) approaches. The study employs a screening method based on the Headspace-GC/MS technique to efficiently extract and identify volatile organic compounds found in commercial beverages. This methodology provides a rapid and reliable system for assessing the volatile profile of these beverages. The analysis reveals the presence of a total of 40 volatile organic compounds, including esters, terpenes/terpenoids, alkenes, aldehydes, aromatic hydrocarbons, and alcohols. Medium-chain esters were found to dominate the volatile profile of the beverages, suggesting a significant contribution to their fragrance and taste. This study offers valuable insights into the volatile profile of commercial beverages, creating awareness among consumers about the flavor components present in these products. By understanding the volatile composition, consumers can make informed choices regarding their beverage consumption. The comprehensive analysis provided by this research serves as a foundation for further studies related to flavor characterization and optimization in commercial beverages.

This paper presents the application of sodium aluminate, directly or after small adjustments in concentration and purity, in some other valuable intermediary products. Sodium aluminate is an intermediary product in Bayer technology applied by Alum SA Tulcea production of alumina and alumina products. Mainly, sodium aluminate is a carrier of aluminum hydroxide between important manufacturing stages in the Bayer process, bauxite processing, and aluminum hydroxide crystallization. After a short investigation of the uses of sodium aluminate, it was decided to choose and study the possibility of converting this secondary product into ecological material for the treatment of natural or industrial wastewater. Actually, on the market, products similar to sodium aluminate from Alum SA Tulcea provide treated waters with high purity and reasonable quality, excellent coagulation rates, rapid flotation, and sedimentation, and in addition, significant side effects, such as excellent removal of phosphorus and silica from treated water. Treatments do not require lime or hydroxide to control alkalinity, and chemical sludge remains at a minimum volume and mass. The test performed with sodium aluminate from Alum SA Tulcea was comparable with other tests with Al2(SO4)3 and FeCl3. The maximum removal yields of global organic load expressed by chemical oxygen demand (COD) and biochemical oxygen demand (BOD5), chromium (Cr VI), and total suspended solids (TSS) were: 83%COD, 71% BOD5, 99.7% Cr VI and 93% TSS.