Vicente de Oliveira Sousa Neto

Evaluation of a low-cost adsorbent for removal of toxic metal ions from wastewater of an electroplating factory.

In this study, sugar cane residue or bagasse was used for removal of toxic metal ions from wastewater of an electroplating factory located in northeast Brazil. Prior acid treatment increased the adsorption efficacies in batch wise experiments. The microstructure of the material before and after the treatment was investigated by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Column operations showed that removals of Cu(2+), Ni(2+) and Zn(2+) from wastewater (in the absence of cyanide) were 95.5%, 96.3.0%, and 97.1%, respectively. Regeneration of the adsorbent obtained in acid indicated that the efficiencies decreased only after the fourth cycle of re-use. Acid-treated sugar cane bagasse can be considered a viable alternative to common methods to remove toxic metal ions from aqueous effluents of electroplating industries.

Determination of Insecticide Residues in Vegetal Fruits

Pesticides compounds represent an important class of pollutants for food, soil and surface water resources. Thus, a simplified method using gas chromatography was used for determining five insecticide residues in fruit samples produced in Ceara State (Brazil). The insecticides were simultaneously extracted from the fruit samples with a mixture of water-methanol (1 : 1% v/v) from lipid-containing crops and then reextracted with ethyl acetate. Cleanup by silica gel column chromatography was not necessary. The extracts were analyzed by GC-ECD. Analytical parameters, such as limit of detection (LOD), limit of quantification (LOQ), linearity, precision, and recovery were considered for the orange fruit. A sufficient recovery of 52.1, 57.0, 49.5, and 108.5% for parathion methyl, malathion, chlorpyrifos, and 2,4-dichlorophenol was found. The compounds 2,4-dichlorophenol, malathion, parathion methyl, and chlorpyrifos were found in all the fruit samples analyzed.

Biomass Adsorbent for Removal of Toxic Metal Ions From Electroplating Industry Wastewater

Ronaldo Ferreira do. Nascimento1, Francisco Wagner de Sousa1, Vicente Oliveira Sousa Neto2, Pierre Basilio Almeida Fechine1, Raimundo Nonato Pereira Teixeira3, Paulo de Tarso C. Freire1 and Marcos Antonio Araujo-Silva1 1Universidade Federal do Ceara (UFC), 2Universidade Estadual do Ceara (UECE-CECITEC), 3Universidade Regional do Cariri (URCA), 4Instituto Federal de Educacao, Ciencia e Tecnologia (IFCE-Crateus) Brazil

Polymer Gels: Molecular Design and Practical Application

Polymer gels are worn in our steadily lives for extended wear lenses, superabsorbent polymers, etc., and more fancy applications are in development. They are among the most interesting and functional materials. Gels are characterized as polymers and their swollen matters with three-dimensional chain structures that are insoluble in any solvents. The capacity of polymer gels to experience considerable swelling and crumpling as an element of their surroundings is a standout among the most admirable properties of these materials. Polymer gels ordinarily contain a lot of portion of solvent, which gives them a singular quality started from a fluid nature. Additionally, they can keep up shape like strong materials, unless extra stress is applied. Subsequently, the mix of flexibility and shape maintenance capacity gives special properties, especially mechanical properties. Gels are wet and moldable and resemble a strong material yet are set up for experiencing considerable distortion. This property is as opposed to most modern materials, for example metals, earthenware production, and plastics, which are dry and hard. This chapter focuses on polymer gels in terms of molecular design, assembly, crosslink formations, and practical application.

Hybrid polymers composite: Effect of hybridization on the some propers of the materials

Abstract In recent years, ecological awareness and other environmental issues led to the development of composite materials based on renewable resources. These materials are environment-friendly and low-cost alternatives to replace synthetic fibers like glass and carbon fibers. Composite materials are heterogeneous mixtures of two or more homogeneous phases with properties that could not have been obtained separately. The polymeric matrix materials with suitable and proper filler, better filler/matrix interaction together with advanced and new methods or approaches are able to develop polymeric composites with great prospective applications in constructions and buildings, automotive, aerospace, and packaging industries. In this context, hybrid bio-based composites that exploit the synergy between natural fibers in a nano-reinforced bio-based polymer can lead to improved properties along with maintaining environmental appeal. This chapter will present some properties of the above-mentioned eco-friendly and bio-degradable hybrid polymer composites and the best possible applications of this kind of materials.

Recent Development of Chitosan Nanocomposites with Multiple Potential Uses

This chapter reviews an actual relevant literature about the most important methods used in the processing of chitosan nanocomposites, which are based on most extensively used biodegradable polymer matrices. A particular attention has been focused on the biodegradable polymer chitosan because of their widespread use in the bionanocomposite films field. Thus, the processing procedures and the results obtained of various applications from chitosan nanocomposite films have been compiled. The current research trends in chitosan-based material films for applications, including biodegradable composites and the use of chitosan are presented. This chapter will increase the interest of researchers in chitosan-based chitosan nanocomposites and the development of new ideas in this field.