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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Microwave Irradiation,2-Amino-4H-chromenes,Ilmenite,Three-component reaction
- چکیده:
- چکیده انگلیسی: A green and highly efficient method has been developed for the synthesis of 2-amino-4H-chromene derivatives in the presence of FeTiO3 as magnetic catalyst via one-pot three-component condensation reaction of aromatic aldehydes, malononitrile and α- or β-naphthol without solvent under microwave irradiation. Mild reaction conditions, short reaction times, simple work-up, use of an economically convenient catalyst, and excellent product yields are the advantageous features of this method. The catalyst can be easily recovered by a simple magnetic separation and can be recycled six times with no significant loss of catalytic activity.
- انتشار مقاله: 21-04-1396
- نویسندگان: Saeid Taghavi Fardood,Ali Ramazani,Pegah Azimzadeh Asiabi,Yousef Bigdeli Fard,Behrooz Ebadzadeha
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Chitosan,Cadmium,Langmuir,Modified biochar,Peanut shell
- چکیده:
- چکیده انگلیسی: In this paper, biochar was prepared from peanut shells, and then the pristine biochar (PBc) was modified by chitosan (CBc). The characteristics of the absorbents were investigated using infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer, Emmett and Teller analysis (BET). The effects of the biochars dosage, pH, initial cadmium concentration, and contact time on cadmium removal were evaluated. Adsorption isotherms and kinetic models were used to explain the adsorption process. The results indicated that CBc could be used as a biosorbent for the removal of heavy metals from the aqueous solution. The adsorption data conformed best to the Langmuir isotherm. Optimum conditions for the highest removal of Cd (II) were obtained at the biochar dosage of 0.6 g/L, 30 mg/L initial concentration of Cd (II) solution, pH value of 6, and within 30 minutes. The maximum adsorption capacities of pristine and modified biochar were found to be 40 mg/g and 58.823 mg/g, respectively. The kinetic data displayed that pseudo-second-order kinetic model can well fit the process of cadmium biosorption. The coatings of biochar with chitosan can greatly improve the absorbent efficiency in the removal of heavy metals and the chitosan-modified biochar can be used as a, low-cost, effective and environmental-friendly adsorbent.
- انتشار مقاله: 11-05-1399
- نویسندگان: Hadiseh Shabani,Mohammad Amir Delavar,Saeid Taghavi Fardood
- مشاهده