Co(II) Recovery from Electronic Waste based on Ion-imprinting of Reduced Schiff base Ligand on Magnetite

( John Edward L. Sio ),( Grace M. Nisola ),( Rosemarie Ann I. Cuevas ),( Khino J. Parohinog ),( Hiluf T. Fissaha ),( Lawrence A. Limjuco ),( Seong-poong Lee ),( Wook-jin Chung ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

The continuous increase in the number of electronic wastes(e-waste) worldwide has caused awareness to salvage these materials as secondary sources of critical metals. Spent lithium-ion batteries (LIBs) in E-waste, used mobile phones and computers contain Li, Ni, Co, Al, and Mn.Cobalt is considered as a critical metal thatcan be recycled into other materials such as magnets, alloys, electroplating, andin LIB and printed circuit boards (PCBs). Thus, selective Co(II) extraction and recovery from secondary sources is of great importance.Schiff base ligands have so far been used as extractants in liquid-liquid extraction (LLE) for Co(II) recovery. Some examples of Schiff bases are synthesized via condensation of 2-aminothiazoles with substituted benzaldehydes. Synthesis of the ligand for Co(II) adsorption is relatively cheap and convenient. However, Schiff bases are susceptible to acid hydrolysis, especially during desorption of Co(II). Thus, slight modification of the imine group to amine by mild reduction was required to render the ligand acid-resistant while it retains its complexing ability with Co(II). Two starting materials for the synthesis of the Schiff base ligand were prepared, 4-allyloxy-2-hydroxybenzaldehyde (AHB) and 2-amino-4-methylthiazole (ATZ). Condensation reaction between AHB and ATZ was carried out to form the Schiff base product (AHB-ATZ), which was further reduced by NaBH4 (r-AHB-ATZ). All synthetic compounds were confirmed via infrared spectroscopy (FTIR), proton and carbon nuclear magnetic resonance spectroscopy (1H-NMR and ¹³C-NMR). While LLE is the conventional system of application, a more practical approach to minimize reagent use and simplify the process is to incorporate r-AHB-ATZ in ion-imprinted polymers (IIPs). IIPs have recently attracted considerable attention in the recovery of metal ions including Co(II). Integration of IIPs with magnetic particles provides the recyclability and reusability of the extracting material after selective adsorption and desorption of Co(II).For the material support, bare magnetite (Fe₃O₄) was prepared by co-precipitation method of FeCl₃/FeCl₂ (2/1) under basic conditions. Its surface was modified with silica by tetraethylorthosilicate(Fe₃O₄@SiO₂) and alkene by 3- methacryloyloxypropyltrimethoxysilane (Fe₃O₄@SiO₂-MATES). Then, radical polymerization between the Fe₃O₄@SiO₂-MATES and r-AHB-ATZ was carried out using azobisisobutyronitrile (AIBN) as radical initiator and ethylene glycol dimethacrylate(EGDMA) as cross-linker in the presence and absence of Co(II) to produce Fe₃O₄@SiO₂-MATES-IIP and non-ion-imprinted material (Fe₃O₄@SiO₂-MATES-NIP), espectively.Fe₃O₄ and its functionalization were characterized by FTIR. Further material characterization and adsorption tests for the selective extraction and recovery of Co(II)are on-going.This work was supported by National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2017R1D1A1B03028102 and 2017R1A2B2002109) and Ministry of Education (2009-0093816 and 22A20130012051 (BK21Plus)).

The Effect of Expertise on Creative Problem Solving

Sio Ut Na 대한사고개발학회 2006 The International Journal of Creativity & Problem Vol.16 No.1

ISDN Challenge in Singapore ( 싱가폴의 ISDN 전략 )

Sung Sio Ma 한국통신학회 1985 한국통신학회 학술대회 및 강연회 Vol.1985 No.-

TRAVELERS' BEHAVIOR AND SATISFACTION TOWARD MACAU TOURISM-AN EMPIRICAL STUDY OF INDIVIDUAL VISITORS FROM MAINLAND CHINA

NG.Sio-wang 세계문화관광학회 2006 Conference Proceedings Vol.7 No.0

The purpose of the paper is to study the overall satisfaction and the traveling behavior travelers (visitors) of Mainland China during their visit to Macau, SAR China. In order to study travelers' overall satisfaction towards local tourism tangible and intangible tourism facilities, qualitative approach of depth-interview was conducted in order to generate insights of variables for proper questionnaire formulation and further quantitative analysis. Followed by the face-to-face questionnaire interview with 436 tourists, it was found that travelers are in general satisfied with local tourism 'hardware' and 'software' facilities such as the "hygiene", "safety", "infrastructure". In the traveling behavior, it was found that "going for casino" plays a major activity for visits instead of "going for sightseeing". The research findings serve as a crucial reference for local tourism practitioners in understanding the attitude and behavior of travelers from mainland China.

Synthesis Of Photo-Active Azo Compounds And Its Application To Cs+ Extraction From Aqueous Solutions

John Edward Sio(존 에드워드 시오),Grace Nisola(그레이스 니솔라),Erwin Escobar(에스코바 어윈),Wook-Jin Chung(정욱진) 대한환경공학회 2021 대한환경공학회 학술발표논문집 Vol.2021 No.11

Reduced Schiff Base-Decorated Magnetite for Removal of Heavy Metal Ions from Aqueous Solution

John Edward L. Sio,Grace M. Nisola,Rosemarie Ann I. Cuevas,Khino J. Parohinog,Hiluf T. Fissaha,Lawrence A. Limjuco,Seong-Poong Lee,Wook-Jin Chung 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

대장절제술 환자에서 수술 전 경구용 Carbohydrate-Rich 음료 복용과 인슐린 저항성 관계

체리안시오 ( Cherry Ann Sio ),정규환 ( Kyuw Han Jung ),강성범 ( Seong Bum Kang ),김덕우 ( Duk Woo Kim ),오흥권 ( Heung Kwon Oh ),윤미옥 ( Miok Yoon ) 한국정맥경장영양학회 2015 한국정맥경장영양학회지 Vol.7 No.2

Purpose: Reducing preoperative fasting time showed positive effects in several studies, and current guidelines suggest use of a preoperative oral carbohydrate-rich solution before elective surgeries. For elective colectomy procedures, some surgeons favor two-day bowel preparation with diet restriction and administration of laxatives. Aside from patients experiencing the discomfort of nil per os (NPO), there are reported benefits regarding intake of liquids until at least two hours prior to surgery, including decrease in insulin resistance, without additional postoperative surgical complications. The aim of this study is to show the benefits of administration of oral rehydration solution (ORS) two hours prior to surgery for patients undergoing elective colectomy, particularly postoperative insulin resistance. Methods: This is a randomized controlled trial. All patients undergoing elective colectomy were included and randomized to the control arm or treatment arm. The control arm consisted of the standard bowel preparation and one day of NPO, while the treatment arm consisted of the standard bowel preparation and allowing intake of carbohydrate-rich ORS until 2 hours before surgery. The insulin, glucose, cortisol, and triglyceride levels were determined immediately after induction, 6 hours, 24 hours, and 48 hours post-op, and compared. The homeostatic model assessment-insulin resistance, insulin, glucose, cortisol, and triglyceride levels were determined and compared between the two groups. Anxiety and postoperative complications were monitored and assessed as well. Results: There was less insulin resistance in patients who received ORS 2 hours prior to surgery. Insulin, glucose, cortisol, and triglyceride levels were lower in the treatment group compared to the control group. Taking ORS 1 day prior and until 2 hours before surgery decreased anxiety and discomfort, and alleviated hunger. Conclusion: Regarding complications, there was no difference in the incidence of aspiration and postoperative complications. There were fewer wound complications and incidence of paralytic ileus in the treatment group.

Value co-creation through corporate social responsibility in a typical controversial industry: Evidence from Macao

Guan Jieqi,Sio Sandy Hou in,Noronha Carlos 한국마케팅과학회 2022 마케팅과학연구 Vol.32 No.1

This paper explores the social values that are created through corporate social responsibility (CSR) disclosure in the gaming tourism industry, and how the industry players use CSR disclosure as a communication channel with their stakeholders. This research applies the content analysis method and collects data from annual reports, sustainability/social reports and corporate websites of all gaming operators in Macao from 2011 to 2017. The results are tied to the Macao government’s report on the gaming tourism industry and the CSR reporting guidelines promulgated by the industry’s regulatory bodies. Further analysis is conducted based on public statistical data to quantify the social value co-created by the industry players with their stakeholders. The findings show that sustainability of enterprises in the gaming tourism industry is created through the participation of various stakeholder groups, such as consumers/customers, government, community, suppliers and employees. This is one of the first studies on value co-creation via CSR disclosure based on companies in the gaming tourism industry, especially in a region under the “one country, two systems” regime. Furthermore, this study pioneers in exploring how companies use CSR reporting to enhance their image and restore social values from their gaming operations which represent a typical controversial sector integrated with tourism.

Culture and Tourism

Aluí,sio Finazzi Porto 세계문화관광학회 2010 International Journal of Culture and tourism Resea Vol.3 No.1

The objective of this work is to try and gain a better understanding about the motives that lead a tourist to visit Brazil, an also to gauge the final perception of the tourist about their visit. The question "why do people travel to Brazil" is complex, involving cultural and psychological aspects (like the attraction for latin culture or for the tropical heat), transport, availability of tourist facilities, distance, motivation and economic considerations. All of this we call the "tourist experience". There is also the fact to be considered, revisit rate, by the tourist, to Brazil is high. In 2006, 64% of the tourists interviewed by Embratur, already had visited the country at least one time. That shows a high fidelity for the quality of the Brazilian reception. What is the reason for this fidelity, how does it happen, also what is the final image the foreign tourist has about Brazil, these are the foci of the research in question. One of the major reasons for the image of Brazil in the outside world, as well as being the period with the most visits by foreign tourists, Carnival is by definition a focus of the research.

Culture and Tourism

Aluí,sio Finazzi Porto 세계문화관광학회 2010 Conference Proceedings Vol.11 No.0

The objective of this work is to try and gain a better understanding about the motives that lead a tourist to visit Brazil, an also to gauge the final perception of the tourist about their visit. The question "why do people travel to Brazil" is complex, involving cultural and psychological aspects ( like the attraction for latin culture or for the tropical heat), transport, availability of tourist facilities, distance, motivation and economic considerations. All of this we call the "tourist experience". There is also the fact to be considered, revisit rate, by the tourist, to Brazil is high. In 2006, 64% of the tourists interviewed by Embratur, already had visited the country at least one time. That shows a high fidelity for the quality of the Brazilian reception. What is the reason for this fidelity, how does it happen, also what is the final image the foreign tourist has about Brazil, these are the foci of the research in question. One of the major reasons for the image of Brazil in the outside world, as well as being the period with the most visits by foreign tourists, Carnival is by definition a focus of the research.