6 documents found, page 1 of 1
Effect of briquetting and coal moisture control processes on coke quality.
Carias, Marina do Carmo; Silva, Guilherme Liziero Ruggio da; Assis, Paulo Santos; Santos, Cláudio Gouvêa dosRecently issues faced by cokemakers connected with availability of resources, coal quality and price, and environmental concerns have led to the development of coal pre-treatment. Aiming the use of semi-coking coal, technologies for increasing bulk density have been applied such as briquetting and coal moisture control (CMC) which have proved their benefits on manufacturing of a strong metallurgical coke. This ...
Manganese ore tailing : optimization of acid leaching conditions and recovery o...
Santos, Olívia de Souza Heleno; Carvalho, Cornélio de Freitas; Silva, Gilmare Antônia da; Santos, Cláudio Gouvêa dosManganese recovery from industrial ore processing waste by means of leaching with sulfuric acid was the objective of this study. Experimental conditions were optimized by multivariate experimental design approaches. In order to study the factors affecting leaching, a screening step was used involving a full factorial design with central point for three variables in two levels (23). The three variables studied w...
Rendering wastes obtained from gold analysis by the lead-fusion fire-assay meth...
Magalhães, Fernanda Batalha de; Carvalho, Cornélio de Freitas; Carvalho, Eduardo Lyse Corrêa Netto; Yoshida, Maria Irene; Santos, Cláudio Gouvêa dosThe classical method of melting lead by fire-assay (Pb-FA) is the most frequently used analytical technique in gold prospection. The crucible solid waste which is generated in this process is usually characterized by chemical and mineralogical composition, granulometric size distribution, and classified according to Brazilian Environmental Regulations. This study demonstrates how acid leaching can be used to re...
Chemical modification of lignocellulosic materials by irradiation with Nd-YAG p...
Botaro, Vagner Roberto; Santos, Cláudio Gouvêa dos; Arantes Júnior, Gilberto; Costa, Adilson Rodrigues daMost reports about modification of lignocellulosics are mainly based on chemical modifications such as specific reactions on hydroxyl groups of cellulose. In this work, we describe the irradiation of Whatman 5 filter paper, microcrystalline cellulose and organosolv lignin with Nd-YAG laser pulses at 1064 nm. The chemical and structural properties of the degraded products were investigated by using FTIR and UV s...
A 2D model of the dynamic of the collision : I 2 -polymeric liquid surfaces of ...
Leal, Alexandre Soares; Santos, Cláudio Gouvêa dos; Quintella, Cristina Maria Assis Lopes Tavares da Mata Hermida; Schor, Heloiza Helena RibeiroEste artigo apresenta um modelo em duas dimensões para o espalhamento de I 2 pela superfície de líquidos poliméricos: poliéterperfluorado (PFPE), polidimentilsiloxano (PDMS) e esqualano. A função energia potencial adotada para descrever a interação do gás com a superfície líquida formulada é do tipo LEPS. Cada molécula diatômica I 2 e o potencial I-superfície são representados como uma função de Morse, com parâ...
Determination of biodiesel adulteration with raw vegetable oil from ATR-FTIR da...
Soares, Itânia Pinheiro; Rezende, Thais Fonseca; Pereira, Rita de Cássia C.; Santos, Cláudio Gouvêa dos; Fortes, Isabel Cristina PereiraTrês origens diferentes de biodiesel (algodão, mamona e palma) foram adulteradas com óleo de soja cru, em concentrações variando de 1 a 40% (m/m). Estas amostras foram analisadas por espectrometria de infravermelho médio (MIR) e os seus espectros foram estudados em três diferentes faixas espectrais: espectro inteiro (4000-665 cm -1 ), e nas faixas de 1800-1700 cm -1 e 1800-1000 cm -1. Para determinar a origem d...