The composite membranes of zirconium oxide-cellulose acetate were prepared in a twostep procedure combining the phase-inversion method and deposition-hydrolysis technique. The first step allowed the preparation of membranes with different morphologies, and the second step allowed a highly dispersed metal oxide to be deposited on the membranes. The XPS O1s binding energy indicated that the interaction between the oxide and the cellulose matrix is probably of hydrogen bonding type. Phosphate retentions were 75 and 90% for the composite membrane in permeation experiments. The water fluxes for a pressure of 1.7 atm were (3.7 ( 1.7) × 10 -2 and (13.0 ( 2.1) × 10 -2 mL min -1 cm -2 . The membranes are very stable under continuous use. Regeneration of the membrane using NaOH 0.01 M eluent solution did not decrease significantly, ca. 10%, the membrane efficiency. The great advantage of these membranes is the low operational pressure required to obtain high phosphate retention.

A remote experiment was developed and carried out to create a phenol/water phase diagram using a low-cost automated data collection system and an online video broadcast. Both the data and video from the experiment were transmitted in real-time. The remote lab experiment was evaluated using qualitative and quantitative questionnaires filled out by the students. The phenol/water phase diagram obtained is entirely consistent, with precision and accuracy compatible with what is expected to be achieved in conventional lab classes. The activity evaluation showed excellent acceptance by the students by doing this lab activity remotely.

The use of information and communication technologies in education and teacher training is a topic investigated in various areas of knowledge. Recognizing aspects related to pedagogical problematization using specific technologies beyond the technical use of resources in pedagogical practices has also been a concern in this ​​research area. In this scenario, the Remote Laboratories present tools that can contribute to developing experimental practices, incorporating technologies that contribute to the student's scientific education. This work investigates the perceptions of chemistry students and science teachers regarding an activity that involves a practical activity in the Remote Laboratory. Data collection was using questionnaires, analyzed qualitatively through the Discursive Textual Analysis technique. Results show positive perceptions about this type of laboratory in terms of its versatility to face real problems and in environments with few resources and possibilities for pedagogical actions aimed at working with active methodologies, promoting student participation. Most of the negative perceptions refer to aspects that are not directly related to the remote laboratory but are associated with the investigative nature of the activity. Some perceptions refer to topics to be improved, such as the delay in the experiment transmission. It was possible to promote a process of reflection on the use of these resources.

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Neste trabalho, utilizando uma coleta automatizada de dados, realizaram-se experimentos tradicionais de Química, como destilação fracionada de mistura água/etanol e água/acetona, reação oscilante Briggs-Rauscher, cinética da decomposição de tiossulfato catalisada por ácido e entalpia de decomposição catalítica de peróxido de hidrogênio. Para esse conjunto de experimentos, utilizou-se uma coleta local de dados, em que o objetivo era adequar as condições de medida à instrumentação alternativa, que foram utilizadas para a realização de experimentos remotos. A instrumentação alternativa significa o uso de pequenos dispositivos baratos e facilmente encontrados no mercado, como: um sensor de temperatura LM35, laser vermelho, sensor LDR, sensor de temperatura DS18B20, Plataforma de prototipagem eletrônica Arduino, ESP8266-NodeMCU e Módulo WiFi ESP8266.Na primeira etapa, um sensor de temperatura e um sistema laser-LDR foram acoplados à placa de aquisição, e os dados foram coletados usando o software da placa e, posteriormente, analisados usando um software de processamento de dados. Com os sistemas desenvolvidos nessa etapa, quatro experimentos foram realizados remotamente, via Internet, usando o site do YouTube e a plataforma Moodle. Nessa etapa, todos os experimentos foram transmitidos a estudantes de diferentes disciplinas, e posteriormente avaliados por questionários qualitativos e quantitativos aplicados aos alunos. Em todos os experimentos os resultados experimentais concordaram adequadamente com os da literatura, com precisão e exatidão compatíveis com o que se espera no ensino experimental convencional. A aplicação dos questionários aos alunos que vivenciaram os experimentos remotamente mostrou uma excelente aceitação por parte dos mesmos, evidenciando a positividade na utilização do recurso da experimentação remota.