Large scale recycling of steel slag as a cementitious additive to cement mortar and/or concrete was investigated in this paper. As the material component of steel slag is highly variable, this EAF slag is gathered from plant site of Dong Tien steelmaker in Ba Ria-Vung Tau province. Chemical compositions of slag consist almost the high content of free CaO, MgO and iron, FexOy. Lower content of cementitious mineral C3S, C2S endorses relative low hydraulic reactivity in comparing with Portland cement. After grinding slag to particle size < 90 μm (Blaine 3400 cm2/g), blended cement–steel slag with 10 to 40% by mass of slag were formulated. Both steel slag-cement Portland and steel slag-granulated blast furnace slag (GBFS)-cement Portland system were introduced to analyze early age and later age property of mortar sample. Preliminary results of resistance remark appropriate formulation of 20% of slag. By adding 20% GBFS in such product, practical application could be considered due to the typical enhancement of durability property of cement mortar in severe condition (sulfate, chlorhydric acid). Others, by considering an approach of slag treatment to improve hydraulic reactivity as the GBFS materials model present. The mineralogical composition and some cementitious properties of obtained product would be discussed for a perspective of new clinker steel slag.

The aim of this work was to strengthen the evidence of using micro diatom frustule as a promising candidate for drug loading materials for both hydrophobic and hydrophilic drug models. The morphological, surface elemental composition of diatomite powder, a raw source of micro diatom frustules and purified diatomite to collect micro diatom frustule were investigated. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) confirmed again the porous silica structure of micro diatom structure as well as validated a necessity of raw diatomite purification before using. UV- vis was used to measure drug loading content of untreated and treated surface of micro diatom frustule with maximum loading for hydrophobic and hydrophilic drugs after 24 hours were at 5.48 ± 0.42% and 5.70 ± 0.34, respectively. Moreover, we also proved that the ability of drug adsorption on materials surface by the reduction of specific surface area and pore size of micro diatom frustule after loading using a (Brunauer–Emmett–Teller) BET method. Besides, the hydrophobic loading capacity of materials was affected by surface modification. Based on the results, micro diatom frustule showed a potential for a drug delivery system.