Artigo quimica

SEPARAÇÃO SÓLIDO-LÍQUIDO: CENTRÍFUGAS E PAPÉIS DE FILTRO
Alexander Rangel Bastosa e Júlio Carlos Afonsob,* a Gerência de Conversão de Biomassa, Centro de Pesquisas Leopoldo Miguez de Mello, 21941-915 Rio de Janeiro – RJ, Brasil b Departamento de Química Analítica, Instituto de Química, Universidade Federal do Rio de Janeiro, 21941-909 Rio de Janeiro
– RJ, Brasil
Recebido em 06/10/2014; aceito em 16/01/2015; publicado na web em 23/03/2015

Assuntos Gerais

http://dx.doi.org/10.5935/0100-4042.20150043

Quim. Nova, Vol. 38, No. 5, 749-756, 2015

SOLID-LIQUID SEPARATION: CENTRIFUGES AND FILTER PAPERS. This work describes the fundamentals and evolution of two current solid-liquid separation methods found in the chemical laboratory: the filter paper and the centrifuge. Both methods were developed in the 19th century and are recognized as valuable techniques for industrial and laboratory purposes. However, significant improvements were introduced only from the end of the 19th century. The classical manual centrifuge was replaced by electric models: safety, maximum speed and number of samples that can be centrifuged at a time were greatly increased. The manufacture of filter paper was initially done by hand, but later benefited from papermaking industrial technologies. Many pretreatments of the wooden fibers were developed, particularly after 1880, thus resulting in many filter paper types for qualitative and quantitative applications.
These two separation techniques are also found in various procedures in our everyday life.
Keywords: solid-fluid separation; filtration; centrifugation; filter paper; centrifuge.

MISTURAS

Tabela 1. Diferenças entre misturas e substâncias1

Mistura é um sistema constituído por duas ou mais substâncias, simples e/ou compostas.1,2 As misturas podem ser classificadas como: sólido-líquido, líquido-líquido, líquido-gás, sólido-sólido, sólido-gás e gás-gás. A mistura na qual é possível a detecção de pelo menos uma das substâncias que a compõem