The Experts below are selected from a list of 9741 Experts worldwide ranked by ideXlab platform

Rajender S Varma - One of the best experts on this subject based on the ideXlab platform.

Harshadas M Meshram - One of the best experts on this subject based on the ideXlab platform.

Ying Dan Liu - One of the best experts on this subject based on the ideXlab platform.

  • fabrication of Ammonium Persulfate coated silica microsphere via chemical grafting and its electrorheology
    Journal of Materials Science, 2014
    Co-Authors: Ying Dan Liu, Xuemei Quan, Bo Mi Lee, In Gu Kim, Hyoung Jin Choi
    Abstract:

    Silica/Ammonium Persulfate (APS) microspheres were fabricated by coating APS on the surface of ~2 μm sized silica particles and applied as a candidate for electrorheological (ER) materials. The morphologies of these particles were observed by SEM. Chemical compositions and structure of the particles were confirmed by EDS and FT-IR. Thermogravimetric analysis was used to examine the amount of APS coating on the silica particles. A 10 vol% ER fluid based on the fabricated particles was prepared by dispersing them into hydroxyl group-terminated silicone oil. Typical ER properties were obtained using a rotational rheometer under an applied electric field at a controlled shear rate test. These properties were also correlated with its dielectric spectra.

Claudia Serna - One of the best experts on this subject based on the ideXlab platform.

  • neodymium recovery from scrap magnet using Ammonium Persulfate
    Hydrometallurgy, 2019
    Co-Authors: Erwin Ciro, Andrea Alzate, Esperanza Lopez, Claudia Serna, Oberlando Gonzalez
    Abstract:

    Abstract This study proposes a novel leaching methodology to recover neodymium from scrap magnet using Ammonium Persulfate ((NH4)2S2O8) solutions. The Nd Fe B magnets from obsolete Hard-Disk-Drives were physically treated by thermal demagnetization (400 °C, 45 min) and mechanical crushing ( Fe B magnets and recover of neodymium sulfate. The influence of (NH4)2S2O8 concentration (0.7–1.3 M), temperature (25–75 °C) and L/S ratio (25–50 mL/g) on Nd Fe B magnets leaching was investigated employing analysis of variance in a 23 full factorial experimental design. At the optimal conditions, quantities >98% of Nd Fe B magnets were leached after 15 min reaction time. Neodymium sulfate was selectively recovered as crystals, and evaluated by chemical and crystallographic analyses. The findings presented in this investigation suggest that neodymium could be recovered from scrap magnet using an eco-friendly leaching methodology assisted by Ammonium Persulfate.

  • recovery of gold from waste electrical and electronic equipment weee using Ammonium Persulfate
    Waste Management, 2016
    Co-Authors: Andrea Alzate, Maria Esperanza Lopez, Claudia Serna
    Abstract:

    This paper presents a novel methodology to recover gold from waste electrical and electronic equipment (WEEE) using Ammonium Persulfate ((NH4)2S2O8). Gold was recovered as a fine coating using substrate oxidation without shredding or grinding process. The WEEE sample was characterized giving values of Au: 1.05g/kg, Fe: 86.00g/kg, Ni: 73.64g/kg, Cu: 26.65g/kg. The effect of (NH4)2S2O8 concentration (0.22-1.10M), oxygen (0.0-1.4L/min) and L/S ratio (10-30mL/g) on the main responses (substrate oxidation and Au recovery) was investigated implementing response surface methodology with numerical optimization. A quadratic model was developed and quantities greater than 98% of Au were recovered. The findings presented suggest that, optimized quantities of Ammonium Persulfate in aqueous highly oxygenated media could be used to extract superficial gold from WEEE.

Oberlando Gonzalez - One of the best experts on this subject based on the ideXlab platform.

  • neodymium recovery from scrap magnet using Ammonium Persulfate
    Hydrometallurgy, 2019
    Co-Authors: Erwin Ciro, Andrea Alzate, Esperanza Lopez, Claudia Serna, Oberlando Gonzalez
    Abstract:

    Abstract This study proposes a novel leaching methodology to recover neodymium from scrap magnet using Ammonium Persulfate ((NH4)2S2O8) solutions. The Nd Fe B magnets from obsolete Hard-Disk-Drives were physically treated by thermal demagnetization (400 °C, 45 min) and mechanical crushing ( Fe B magnets and recover of neodymium sulfate. The influence of (NH4)2S2O8 concentration (0.7–1.3 M), temperature (25–75 °C) and L/S ratio (25–50 mL/g) on Nd Fe B magnets leaching was investigated employing analysis of variance in a 23 full factorial experimental design. At the optimal conditions, quantities >98% of Nd Fe B magnets were leached after 15 min reaction time. Neodymium sulfate was selectively recovered as crystals, and evaluated by chemical and crystallographic analyses. The findings presented in this investigation suggest that neodymium could be recovered from scrap magnet using an eco-friendly leaching methodology assisted by Ammonium Persulfate.