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Alkylation of toluene with t-butyl alcohol over zeolite catalysts / Hong-jun Dong in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2091–2095 Titre : Alkylation of toluene with t-butyl alcohol over zeolite catalysts Type de document : texte imprimé Auteurs : Hong-jun Dong, Auteur ; Shi Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2091–2095 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Alkylation;  Toluene;  t-Butyl  Alcohol;  Zeolite  Catalysts Résumé : Alkylation of toluene with tert-butylalcohol was investigated over three zeolite catalysts (HY, Hβ, and HMCM-22). The acid properties of zeolites were characterized by FT-IR. The fact that the reaction was influenced by the mount of acid was discussed emphatically, and the reaction temperature on conversion of toluene and selectivity for 4-tert-butyl toluene was also studied. The main products have been identified as 4-tert-butyltoluene and 3-tert-butyltoluene. The best result was obtained when temperature was 473 K, the space velocity was 4.0 h−1, and the mole ratio of toluene to tert-butylalcohol was 6. Zeolite HMCM-22, with the highest total acid and the lowest ratio of the total B acid to the total L acid, possessed high activity for toluene conversion and high paraselectivity over the three types of zeolite catalysts. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901080t [article] Alkylation of toluene with t-butyl alcohol over zeolite catalysts [texte imprimé] / Hong-jun Dong, Auteur ; Shi Li, Auteur . - 2010 . - pp. 2091–2095. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2091–2095 Mots-clés : Alkylation;  Toluene;  t-Butyl  Alcohol;  Zeolite  Catalysts Résumé : Alkylation of toluene with tert-butylalcohol was investigated over three zeolite catalysts (HY, Hβ, and HMCM-22). The acid properties of zeolites were characterized by FT-IR. The fact that the reaction was influenced by the mount of acid was discussed emphatically, and the reaction temperature on conversion of toluene and selectivity for 4-tert-butyl toluene was also studied. The main products have been identified as 4-tert-butyltoluene and 3-tert-butyltoluene. The best result was obtained when temperature was 473 K, the space velocity was 4.0 h−1, and the mole ratio of toluene to tert-butylalcohol was 6. Zeolite HMCM-22, with the highest total acid and the lowest ratio of the total B acid to the total L acid, possessed high activity for toluene conversion and high paraselectivity over the three types of zeolite catalysts. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901080t

Attrition studies of an iron fischer–tropsch catalyst used in a pilot-scale stirred tank slurry reactor / Tie-jun Lin in Industrial & engineering chemistry research, Vol. 51 N° 40 (Octobre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 40 (Octobre 2012) . - pp. 13123–13131 Titre : Attrition studies of an iron fischer–tropsch catalyst used in a pilot-scale stirred tank slurry reactor Type de document : texte imprimé Auteurs : Tie-jun Lin, Auteur ; Xuan Meng, Auteur ; Shi Li, Auteur Année de publication : 2012 Article en page(s) : pp. 13123–13131 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Catalysts Résumé : Attrition resistance is a key design parameter for catalysts used in slurry phase Fischer–Tropsch (F–T) reactors, especially for industrial-scale reaction. It is well-known that iron F–T catalyst particles undergo physical attrition and chemical stresses caused by phase transformations. Here we report on attrition properties of a Fe–Cu–K–SiO2 catalyst used in a pilot-scale stirred tank slurry reactor (STSR) under low temperature F–T reaction conditions. The wax-free catalysts were characterized by SEM, EDS, BET surface area measurements, and a Mastersizer 2000 for particle size analysis. The results show that, after 408 h of reaction in an STSR, the particle size reduction due to erosion/abrasion and fracture was apparent. Large reductions in the Sauter mean diameter (93.45%) and the volume moment diameter (71.67%) were observed. The increase in the fractions of particles smaller than 5 and 10 μm was 18.25 and 30.11%, respectively. We concluded therefore that the catalyst underwent more severe attrition in industrial application and the attrition was mainly caused by the fracture of larger or smaller particles. Further study is needed to improve the catalyst attrition resistance. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3014428 [article] Attrition studies of an iron fischer–tropsch catalyst used in a pilot-scale stirred tank slurry reactor [texte imprimé] / Tie-jun Lin, Auteur ; Xuan Meng, Auteur ; Shi Li, Auteur . - 2012 . - pp. 13123–13131. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 40 (Octobre 2012) . - pp. 13123–13131 Mots-clés : Catalysts Résumé : Attrition resistance is a key design parameter for catalysts used in slurry phase Fischer–Tropsch (F–T) reactors, especially for industrial-scale reaction. It is well-known that iron F–T catalyst particles undergo physical attrition and chemical stresses caused by phase transformations. Here we report on attrition properties of a Fe–Cu–K–SiO2 catalyst used in a pilot-scale stirred tank slurry reactor (STSR) under low temperature F–T reaction conditions. The wax-free catalysts were characterized by SEM, EDS, BET surface area measurements, and a Mastersizer 2000 for particle size analysis. The results show that, after 408 h of reaction in an STSR, the particle size reduction due to erosion/abrasion and fracture was apparent. Large reductions in the Sauter mean diameter (93.45%) and the volume moment diameter (71.67%) were observed. The increase in the fractions of particles smaller than 5 and 10 μm was 18.25 and 30.11%, respectively. We concluded therefore that the catalyst underwent more severe attrition in industrial application and the attrition was mainly caused by the fracture of larger or smaller particles. Further study is needed to improve the catalyst attrition resistance. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3014428

Cysteine - based organocatalysts for the highly efficient direct stoichiometric anti - and syn - aldol reactions / Shi Li in Industrial & engineering chemistry research, Vol. 50 N° 24 (Décembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13711-13716 Titre : Cysteine - based organocatalysts for the highly efficient direct stoichiometric anti - and syn - aldol reactions Type de document : texte imprimé Auteurs : Shi Li, Auteur ; Chuanlong Wu, Auteur ; Xiangkai Fu, Auteur Année de publication : 2012 Article en page(s) : pp. 13711-13716 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Organocatalysts  Stoichiometric Résumé : A series of cysteine-based organocatalysts have been designed and synthesized from a simple step. The anti-aldol and syn-aldol products could be obtained with up to 98:2 anti/syn and 99% ee; the stoichiometric ratio between aldehydes and ketones is 1. This catalyst could be easily recovered and efficiently used in large-scale reactions, which demonstrates its potential application in industry. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201482c [article] Cysteine - based organocatalysts for the highly efficient direct stoichiometric anti - and syn - aldol reactions [texte imprimé] / Shi Li, Auteur ; Chuanlong Wu, Auteur ; Xiangkai Fu, Auteur . - 2012 . - pp. 13711-13716. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13711-13716 Mots-clés : Organocatalysts  Stoichiometric Résumé : A series of cysteine-based organocatalysts have been designed and synthesized from a simple step. The anti-aldol and syn-aldol products could be obtained with up to 98:2 anti/syn and 99% ee; the stoichiometric ratio between aldehydes and ketones is 1. This catalyst could be easily recovered and efficiently used in large-scale reactions, which demonstrates its potential application in industry. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201482c

Study on alkylation of toluene with tert - butanol over La2O3 - modified HY zeolite / Lin-bo Chen in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7234–7238 Titre : Study on alkylation of toluene with tert - butanol over La2O3 - modified HY zeolite Type de document : texte imprimé Auteurs : Lin-bo Chen, Auteur ; Hong-jun Dong, Auteur ; Shi Li, Auteur Année de publication : 2010 Article en page(s) : pp. 7234–7238 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Zeolite  catalysts Résumé : Alkylation of toluene with tert-butanol was investigated over La2O3-modified HY zeolite catalysts in the microfixed bed reactor. The affect factors of conversion of toluene and the selectivity of tert-butyltoluene were studied. The main reaction products have been identified as p-tert-butyltoluene and m-tert-butyltoluene, La2O3 modified HY zeolite catalyst can significantly improve the selectivity of p-tert-butyltoluene. The result showed that 5% La2O3-modified HY zeolite catalyst was catalytic active (32.4% conversion of toluene), with para-selectivity near 82% at 473 K after 8 h. At the same time the catalysts were characterized by the X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. The FT-IR results showed that the modifier could increase the concentration of weak B acid of HY zeolite and obviously improve the selectivity of p-tert-butyltoluene. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100695k [article] Study on alkylation of toluene with tert - butanol over La2O3 - modified HY zeolite [texte imprimé] / Lin-bo Chen, Auteur ; Hong-jun Dong, Auteur ; Shi Li, Auteur . - 2010 . - pp. 7234–7238. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7234–7238 Mots-clés : Zeolite  catalysts Résumé : Alkylation of toluene with tert-butanol was investigated over La2O3-modified HY zeolite catalysts in the microfixed bed reactor. The affect factors of conversion of toluene and the selectivity of tert-butyltoluene were studied. The main reaction products have been identified as p-tert-butyltoluene and m-tert-butyltoluene, La2O3 modified HY zeolite catalyst can significantly improve the selectivity of p-tert-butyltoluene. The result showed that 5% La2O3-modified HY zeolite catalyst was catalytic active (32.4% conversion of toluene), with para-selectivity near 82% at 473 K after 8 h. At the same time the catalysts were characterized by the X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. The FT-IR results showed that the modifier could increase the concentration of weak B acid of HY zeolite and obviously improve the selectivity of p-tert-butyltoluene. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100695k