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Pd/SiO<sub>2</sub>-Al<sub>2</sub>O<sub>3</sub> 촉매상에서 아크로레인과 암모니아로 부터 피리딘과 β-피콜린의 합성
천승우,최정근,오석연,나석은,박대원,Chun, Sung-Woo,Choi, Jung-Kun,Oh, Seok-Youn,Na, Suk-Eun,Park, Dae-Won 한국공업화학회 1991 공업화학 Vol.2 No.2
실리카-알루미나에 담지된 팔라듐 촉매를 제조하여 아크로레인과 암모니아로부터 피리딘과 ${\beta}$-피콜린의 합성반응에 사용하였다. 시간이 경과함에 따라 촉매표면에 생성된 침적물에 의하여 촉매의 활성이 크게 감소하였다. TPR 실험 결과 이 침적물은 아크로레인과 암모니아의 축합 중합에 의하여 생성됨을 알 수 있었다. 전화율과 피리딘 및 ${\beta}$-피콜린의 생성속도는 아크로레인의 분압이 증가할수록 감소하였다. 침적물의 양과 촉매재생 온도는 아크로레인의 분압에 따라 증가하였으나 암모니아의 분압에는 큰 영향을 받지 않았다. $Pd/SiO_2-Al_2O_3$ catalysts were prepared for the synthesis of pyridine and ${\beta}$-picoline from acrolein and ammonia. The activity of these catalysts decreased considerably by the formation of deposits on catalyst surface during the reaction. TPR study showed that the deposits were formed by the condensation polymerization of acrolein and ammonia. The conversion and production rate of pyridine and ${\beta}$-picoline decreased with the partial pressure of acrolein. The amount of deposits and the regeneration temperature of spent catalysts increased with the partial pressure of acrolein but they were independent of the concentration of ammonia.
손미아,백도명,최정근,박수경,박정순,오세민,박정선,박동욱,Son, Mi-A.,Paek, Do-Myung,Choi, Jung-Kun,Park, Su-Kyeong,Park, Jung-Soon,Oh, Se-Min,Park, Jung-Sun,Park, Dong-Ook 대한예방의학회 1995 Journal of Preventive Medicine and Public Health Vol.28 No.1
Benzidine Industry in Korea has started after Japan has banned its production in early 1970's, and it has been in operation in Korea for over 20 years. However, it is not known yet whether any bladder cancer has developed from benzidine exposure. This study was done to screen benzidine-exposed workers for bladder cancer, and to examine the feasibility of employing screening test at the workplace. All the workplaces that manufacture or use benzidine for more than 20 years in Korea have been covered in this study, and they include 2 benzidine manufacturing factories, 5 benzidine using factories, as well as 2 benzidine free factories as an outside control. In total, 516 workers were screened with urine stick test and urine cytology test for the evidence of hematuria and abnormal urothelial cells. Each worker was also asked about risk factors and symptoms of bladder cancer including past medical history, smoking, medication and occupational history Benzidine in the air was measured by personal and area sampling. Out of 516 screened workers, 84(16.3%) workers showed positive hematuria in urine stick test, and 7(1.4%) workers showed degenerative cells in urine cytology tests. Those workers with abnormal urine test results who have been exposed to benzidine fo more than 10 years were further screened, and, in total, 23 workers were examined with intra-venous pyelography and cystoscopy. None of those screened had any evidence of bladder cancer When workers with only past hematuria history were included in the positive hematuria group, 96(18.5%) had positive hematuria. On the multiple logistic regression analysis, positive hematuria was significantly associated with benzidine exposure, history of other occupations with elevated bladder cancer risk, pyuria and glycosuria. The association got stronger as direct benzidine exposure was accounted through individual task analysis, and as exposure duration was accounted with tenure analysis. For those with benzidine exposure with more than 10 years of tenure, the odds of having positive hematuria was elevated 2.14(95%C.I is 1.08 to 4.25) times more than for those without exposure. Even though bladder cancer was not detected for several limitations including short observation period, majority of studied workers with short latency, healthy worker effect, and low sensitivity of single screening test in a cross-sectional study, the study results suggest that hematuria screening is a feasible and very useful test for bladder cancer screening among benzidine exposed workers.
아크로레인과 암모니아로부터의 피리딘 합성반응에 대한 공기와 수증기의 영향
박대원,오석연,최정근 한국화학공학회 1992 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.30 No.5
실리카-알루미나에 담지된 팔라듐 촉매상에서 아크로레인과 암모니아로부터의 피리딘 및 β-피콜린 합성반응에 관하여 정상 및 비정상상태 조업을 실시하였다. 적당량의 공기와 수증기는 피리딘과 β-피콜린의 수율을 증가시켰으나 과량 사용시에는 촉매의 활성저하를 초래하였다. 공기에 의한 주기적 촉매재생 조업결과 정상상태보다 피리딘의 수율이 증가하였다. Steady and unsteady state operations for the synthesis of pyridine and β-picoline were carried out with a Pd/SiO₂-Al₂O₃ catalyst. Addition of small amount of air and water vapor increased yield of pyridine and β-picoline but the catalyst was deactivated when they were used in excess. Periodic reactivation of the catalyst with air showed higher yield of pyridine compared to steady-state operation.