2019, Issue 65(69), Fasc. 4 (December)

Contents

pages 1- 8    Download

Synthesis and Characterization of Intermediate Azobenzene Derivatives with Terminal Polar Groups

VICTOR PRICOP, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
EMA SAVA, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
ANA CIȘLARU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
CORINA MĂLUȚAN, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
AUREL SIMION, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
IRINA CÂRLESCU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, icarlescu@ch.tuiasi.ro

pages 9 - 14    Download
Abstract.
The paper presents synthesis and characterization of some intermediate azobenzene compounds containing polar ending groups with the purpose to obtain final bent-core liquid crystals with potential semiconducting properties. The azobenzene compounds were synthetized by diazotization and condensation reaction of the corresponding amine derivatives, 4-(trifluoromethyl)aniline and 4-aminobenzonitrile followed by esterification with 3-hydroxybenzoic acid protected previously with benzyl chloride. All the synthetized compounds were purified by recrystallization or column chromatography and their structures were confirmed by 1H-NMR and 13C-NMR studies. Keywords: azoderivatives; 3-hydroxybenzoic acid; 4-(trifluoromethyl)aniline; 4-aminobenzonitrile.

Recycling Electronic Waste. Study for the Recovery of Precious Metals

RAMONA-ELENA TĂTARU-FĂRMUȘ, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
CORINA CERNĂTESCU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
GABRIELA ANTOANETA APOSTOLESCU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, ganto@ch.tuiasi.ro
CLAUDIA COBZARU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
NICOLAE APOSTOLESCU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
MIHAELA AURELIA VIZITIU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
RALUCA-ELENA BACIU, "Grigore T. Popa" University of Medicine and Pharmacy of Iaşi, Romania, Faculty of Dental Medicine

pages 15 - 26    Download
Abstract
This paper presents the results obtained in recovering precious metals from electronic waste (printed circuit board - PCB) by using simple mechanical and chemical procedures. Collected PCBs were disassembled and the components were separated using density and magnetic separation method. After the chemical recycling processes, the samples were examined by EDAX and SEM, the analysis showing the presence of silver in a mass percentage of 5.29%.
Keywords: gold; silver; printed circuit board; waste management.

Preliminary Studies About Co(II) Metallic Ions Retention from Aqueous Solutions onto PVA-Cellulose Composite Hydrogels

IULIA NEBUNU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
CARMEN ZAHARIA, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
RAMONA-ELENA TĂTARU- FĂRMUȘ, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
RALUCA IOANA BARON, "Petru Poni" Institute of Macromolecular Chemistry of Romanian Academy, Iași, Romania
SERGIU COSERI, "Petru Poni" Institute of Macromolecular Chemistry of Romanian Academy, Iași, Romania
DANIELA ȘUTEU, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, danasuteu67@yahoo.com

pages 27 - 36    Download
Abstract
A direction for the use of composite hydrogel based on PVA and cellulose is the preparation of efficient adsorbents in the adsorption/ sorption/biosorption processes of inorganic chemical species from aqueous systems, including wastewaters. Thus, the PVA-cellulose hydrogel (Ox25C) was studied as adsorbent in the removal of Co2+ metallic ions from aqueous solutions. Batch experimental studies focused on the determination of the influence of some important physical operating parameters on the adsorption of metallic ions, such as: pH, adsorbent dose, phases contact time, temperature, and metal ion concentration were performed. The experimental results recommend the use of PVA-cellulose composite hydrogel (Ox25C) in the removal of heavy metal ions from aqueous systems, predominantly by adsorption process types.
Keywords: adsorption; aqueous medium; hydrogel adsorbent; inorganic chemical pollutants.

Evaluation of Thermal Treatments Effect on Human Hair by Thermal Analysis

ANDREEA CĂLUIAN, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, SC Delphi Tehnologies SRL
TOMINA BRAN, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, Autoliv Romania
ELENA-LUIZA EPURE, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, lepure@tuiasi.ro

pages 37 - 44    Download
Abstract
Hair provides a series of information about the health and lifestyle of people. The article’s topic is focused on the thermal analysis of different human hair samples. Three sample series were examined, so two series were prolong exposed at high and low temperatures, and the third series of samples was maintained at room temperatures. The thermal stability of these samples was evaluated using the Tonset as reference criteria. Even if small differences in the thermogravimetric behavior were observed at the analyzed samples, an interesting fact was observed in the first stage of degradation, the samples kept in warm experimental conditions had a higher thermal resistance than the similar samples from the other two series.
Keywords: human hair; residue; meteo-sensitivity; thermostability; thermal treatments.

Analysis of the Vascular Flora from a Soil Affected by Anthropogenic Sources

TEODORA ALEXANDRA ZOTICA, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
SIMONA DUMITRIȚA CHIRILĂ, "Alexandru Ioan Cuza" University of Iaşi, Romania, Faculty of Biology
CĂTĂLIN BALAN, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
IRINA VOLF, "Gheorghe Asachi" Technical University of Iași, Romania, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, iwolf@tuiasi.ro

pages 45 - 52    Download
Abstract
 The area of study (a length of 385 m and a width of 202 m), located at approximately 10 km outside Iași district (47°09'02.6"N- 27°42'51.5"E), is affected by some anthropic activities such as the proximity of transport infrastructure, accidentally waste disposal and more important by industrial activities. This paper examines the floristic elements from taxonomic, environmental preferences as well as from the phyto-economic potential point of view. This analysis is necessary in order to determine the dominant species, some of which may be considered candidates for a phytoremediation process. Moreover, these data represent inputs for a diagnostic analysis of the polluted area in order to design an ecological restoration plan.
Keywords: ecological indexes; environmental preferences; floral elements; phyto-economic potential; spontaneous flora.