2017, Volume 63(67), Issue 4 (December)

Contents

pages 1- 8     Download

Potential Antimicrobial Activity of Some New Compounds Against Pathogenic Strains

ANCA MIHAELA MOCANU, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, ancamocanu@ch.tuiasi.ro

pages 9 - 15     Download
Abstract:
The objective of this study is to evaluate antibacterial activity of new compounds obtained by the condensation of hydrazides with several substrata (aldehides, transition metals and coupling compounds) affording final compounds with potential biological activities such antibacterial, antifungal, antiviral, antitumor activity, fungicidal, tuberculostatic and plant growth regulative properties. The new compounds were studied for antibacterial activities, in vitro, by measuring zone diameters of bacterial growth inhibition on different types of strains microorganisms: Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The newly analyzed compounds exhibited a variable activity of inhibition on the growth of the bacteria.
Keywords: hydrazide, coupling compounds, microorganisms, difusimetric method, tested activity.

Applications of Reaction Calorimetry in Lignin Chemistry

VALENTINA IORDAN (CONSTANTIN), "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
TEODOR MĂLUȚAN, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, thmalu@tuiasi.ro

pages 17 - 22    Download
Abstract
The thermodynamic properties of lignin and its solutions are important in the design and operation of the machines used in the biomass biorafination schemes. In the literature, there are few thermodynamic data on the main chemical components of biomass (cellulose, hemicellulose and lignin). In this paper we present the heat dissolution (ΔHdis) of the lignin alkaline solutions obtained by the reaction calorimetry. Lignin is characterized by insolubility in most simple solvents. The solubility of lignin preparations also depends on the method used to isolate them.
Since most of the applications in which lignin is subjected to chemical reactions involves the dissolution of lignin, it is very important to know the thermodynamic properties of these solutions as well as the characterization of chemical reactions in terms of heat of reaction.
Keywords: lignin; reaction heat; dissolving heat; specific heat; biomass.

Experimental Equipment Used in the Study of Carbon Dioxide Absorption (I)

RAMONA ELENA TĂTARU FĂRMUȘ, Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, rtataru@ch.tuiasi.ro
MARIA HARJA, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection

pages 23 - 33     Download
Abstract
The continuing increase demand in global energy has led a faster raw material depletion and increased exploitation of hydrocarbon fuels. Before using natural gas, it is necessary to remove acid gases (H2S and CO2), to increase the heating value of natural gas, reduce corrosion, prevent atmospheric pollution. Acid gas removal is best accomplished by chemical absorption. Such washing processes are also used in petroleum refining, coal gasification and hydrogen production. This paper presents a brief chronology of experiments conducted in the study of carbon dioxide absorption in amine solutions, focusing on experimental equipment developed in laboratory research.
Keywords: acid gases; carbon dioxide; experimental devices; flow of absorption.

Microcrystalline Cellulose as Adsorbent for Removal of Dyes from Wastewaters

IULIA NICA, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
GABRIELA BILIUȚĂ, "Petru Poni" Institute of Macromolecular Chemistry of Romanian Academy, Iași
SERGIU COȘERI, "Petru Poni" Institute of Macromolecular Chemistry of Romanian Academy, Iași
CARMEN ZAHARIA, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
DANIELA ȘUTEU, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, danasuteu67@yahoo.com

pages 35 - 44     Download
Abstract
Batch adsorption studies were carried out for the adsorption of some dyes (Brilliant Red HE-3B, Orange 16, Rhodamine B and Methylene Blue) onto a new versatile cellulose-based product (Cellet), to be a new adsorbent. Studies were shown that the adsorption process is influenced by the chemical structure of dyes and experimental working conditions, i.e. pH, initial dye concentration, cellulose dose, phases contact time and temperature. The obtained results were shown that this cellulose-based product (Cellet) can be use as an adequate adsorbent in discoloration of textile effluents.
Keywords: adsorption; aqueous medium; microcrystalline cellulose; organic dye.

Influence of Natural Extracts on the Quality of Cold Sodium Soap

CLAUDIA COBZARU, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
CRINA CALENCIUC, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
ADRIANA GHEORGHINA, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection
CORINA CERNĂTESCU
, "Gheorghe Asachi" Technical University of Iași, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, ccernatescu@yahoo.com

pages 45 - 52    Download
Abstract
In this study, toilet soaps containing a mixture of natural fruit and vegetable extracts were prepared. The results show that the three vegetable oils (olive, palm and coconut oil) used as a source of fatty acids, due to their acidity index, iodine and saponification index, are a good raw material for making soap. Furthermore, they contain vitamins and antioxidants, which, together with those contained in the natural extracts mixture obtained from fruits and vegetables, helps to improve the softening and soothing properties of the soap. However, anthocyanin pigments from the natural extracts do not contribute to the colour enhancement of the finished product due to the colour change based on the pH value for the alkaline solution or the soap (neutral pH). For all that reasons, the soap obtained is a quality product because it does not have alkali, and because the glycerine content helps with moisturizing and softening the skin.
Keywords: soap; natural extracts; cold saponification

Habilitation thesis summary:
Advanced Capitalization of the Fly Ash to Obtain New Materials

MARIA HARJA, "Gheorghe Asachi" Technical University of Iaşi, "Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, mharja@ch.tuiasi.ro

pages 53 - 57    Download
Abstract
The habilitation thesis presents the original and relevant results in the field of capitalization of fly ash, with application in chemical engineering. In this thesis new synthesized low-cost sorbents, based on Holboca ash, were comparative studied for the removal of heavy metals from aqueous solutions. The synthesis method was very simple under room temperature to high conditions and final product can be safely disposed. The ashes are produced in power plants and represent the largest source of energy. The production of this material (the by-product) is estimated to be more than 370 Mt last years. Ash can be modified and used as sorbent efficient for the removal of heavy metals and dyes from solutions. The modified ash has composition similar to natural zeolites. The ash and modified ash present low cost and efficiently adsorbents, which can be used for removal pollutants from water, gas and soil.