One-Step Synthesis and Functionalization of High-Salinity-Tolerant Magnetite Nanoparticles with Sulfonated Phenolic Resin.

Superparamagnetic nanoparticles are being actively developed for various applications in oil fields. A key requirement for such nanoparticles is the long-term stability of their dispersion under harsh subsurface conditions such as high salinity and high temperature. In this study, through functionalization of the surface of the magnetite nanoparticles with a sulfonated phenolic resin, stable dispersions of the nanoparticles in 5 wt % NaCl solution at neutral to basic pH were achieved.

Shredding and liberation characteristics of refrigerators and small appliances.

Mechanical disaggregation, or shredding, is an important part of the recycling process. Occurring at the beginning of the processing sequence, it significantly affects the efficiency of downstream processing stages. This study examines the size reduction and liberation characteristics of the single-stage shredding of household appliances to improve the efficiency and quality of the recycling process.

Beneficiation of coal pond ash by physical separation techniques.

In this study, investigations to develop a beneficiation process for separating coal pond ash into various products were undertaken. To this end, coal pond ash samples with different particle size ranges were tested in terms of their washability characteristics in a float-and-sink analysis. It was found that coal pond ash was heterogeneous in nature consisting of particles that varied in terms of their size and composition.

Identification of Calcium Sulphoaluminate Formation between Alunite and Limestone.

This study was carried out to identify the conditions of formation of calcium sulphoaluminate (3CaO·3Al(2)O(3)·CaSO(4)) by the sintering of a limestone (CaCO(3)) and alunite [K(2)SO(4)·Al(2)(SO(4))(3)·4Al(OH)(3)] mixture with the following reagents: K(2)SO(4), CaCO(3), Al(OH)(3), CaSO(4)·2H(2)O, and SiO(2). When K(2)SO(4), CaCO(3), Al(OH)(3), CaSO(4)·2H(2)O were mixed in molar ratios of 1:3:6:3 and sintered at 1,200∼1,300 °C, only 3CaO·3Al(2)O(3)·CaSO(4) and calcium langbeinite (2CaSO(4)·K(2)SO(4)) were generated. With an amount of CaO that is less than the stoichiometric molar ratio, 3CaO·3Al(2)O(3)·CaSO(4) was formed and anhydrite (CaSO(4)) did not react and remained behind.

A study on removal characteristics of heavy metals from aqueous solution by fly ash.

The purpose of this study was to investigate the possibility of the utilization of coal fly ash as a low cost adsorbent. Batch experiments were conducted to evaluate the removal of heavy metals from aqueous solutions by fly ash under various conditions of metal concentration, pH and fly ash dosage. The heavy metals used in this study were zinc, lead, cadmium and copper.