Universiti Teknologi Petronas

About: Universiti Teknologi Petronas is a education organization based out in Ipoh, Malaysia. It is known for research contribution in the topics: Adsorption & Ionic liquid. The organization has 6127 authors who have published 11284 publications receiving 119400 citations.

Comparison of Using NaOH and KOH Activated Fly Ash-Based Geopolymer on the Mechanical Properties

Abstract: Geopolymer synthesis has two main requirements to fulfil which are the source material that is rich in Silicon (Si) and Aluminum (Al) and alkali activator such as sodium/potassium hydroxide. Sodium hydroxide (NaOH) is widely used for the synthesis of geopolymer compared to potassium hydroxide (KOH) with addition of silicate solution for the purpose of increasing dissolution process. However, the comparison of using different activator in the absence of silicate solution for geopolymer synthesis is not well established. This paper presents an evaluation on compressive strength of fly ash–based geopolymer by using different activator (KOH and NaOH) with respect to different curing conditions (time and temperature) in the absence of sodium silicate. The samples were mixed using mortar mixer and prepared in 50mm x 50mm x 50mm mould for determination of compressive strength. It can be observed that the highest compressive strength up 65.28 MPa was obtained using NaOH. Meanwhile, synthesis using KOH only recorded 28.73 MPa. The compressive strength was better when cured at elevated temperature (60°C) than room temperature (25°C). Further analysis on the microstructure of the highest compressive strength geopolymer samples for both activators was carried out using Field Emission Scanning Microscopy (FESEM) and Raman spectroscopy.

Effect of Ionic Liquid Treatment on Pyrolysis Products from Bamboo

Abstract: In the present work 1-butyl-3-methylimidazolium chloride (BmimCl) and 1-butyl-3-methylimidazolium acetate (BmimOAc) ionic liquids have been used for the dissolution of bamboo biomass. After dissolution the treated samples were precipitated by using water. The calorific value, CHNS content, lignin content, and proximate analysis of the untreated and precipitated material were measured. The BmimCl treated sample was found to have a higher value for calorific value, elemental percentage of carbon, and lignin content as well as fixed carbon, compared to the untreated and BmimOAc treated samples. The untreated and ionic liquid treated samples were also characterized by TGA and XRD. Low thermal stability and change in crystalline form from cellulose Type I to Type II have been observed by the dissolution and precipitation treatment. Pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS) was employed to achieve fast pyrolysis of the untreated and ionic liquid treated samples of bamboo. The desirable products ...