Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding perf...Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.展开更多
This paper presents a study on the chemical properties of amino-carboxylmethyl cellulose (ACMC) and the mechanisms of the reac-tion of ACMC ivith copper ions and the depression of ACMC on CuSO4-ac-tivated stibnite. Th...This paper presents a study on the chemical properties of amino-carboxylmethyl cellulose (ACMC) and the mechanisms of the reac-tion of ACMC ivith copper ions and the depression of ACMC on CuSO4-ac-tivated stibnite. The results of XPS and IR analyses show that after CMC is treated by aqueous ammonia , amino-carboxyl groups form in CMC molecules by H-bonding action ivhich can complex selectively ivith copper ions to form copper-amino-carboxylmethyl cellulose. On the surface of CuSO4-activated stibnite, ACMC is also able to complex strongly with cop-per ions and forms a strong hydrophilic depression film. Because there are the obvious difference of reactions between ACMC ivith Cu2+ and ACMC ivith Hg2+ , the separation of cinnabar from stibnite is successfully realized using ACMC as depressant and CuSO4 as activator.展开更多
The Knoevenagel reaction of aromatic aldehydes with malononitrile and ethyl cyanoacetate proceeds smoothly in the presence of carboxymethyl cellulose supported triethylenetetramine as catalyst in the 95% ethanol to af...The Knoevenagel reaction of aromatic aldehydes with malononitrile and ethyl cyanoacetate proceeds smoothly in the presence of carboxymethyl cellulose supported triethylenetetramine as catalyst in the 95% ethanol to afford the desired E-isomers of the corresponding alkenes in yield of 74%~96% and good purity. The results confirm that the catalyst can offer definite advantages of good activity , easy separation, mild reaction condition and high yields. Moreover, it can be reused for not less than 5 runs.展开更多
Under the condition of microwave radiation the carboxylmethyl starch(CMS)was prepared with solid phase synthesis method.The degree of substitution and viscosity of CMS was affected by radiation time,the volume of sodi...Under the condition of microwave radiation the carboxylmethyl starch(CMS)was prepared with solid phase synthesis method.The degree of substitution and viscosity of CMS was affected by radiation time,the volume of sodium hydroxide and water.The cleaning-aid property of CMS was studied,and compared with that of the traditional synthesis ways.展开更多
The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole (Ag-CMCTS-TBZ) prepared from different materiel ratios were reported. ...The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole (Ag-CMCTS-TBZ) prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.展开更多
基金Project(2012zzts101)supported by the Fundamental Research Funds for the Central Universities,China
文摘Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.
文摘This paper presents a study on the chemical properties of amino-carboxylmethyl cellulose (ACMC) and the mechanisms of the reac-tion of ACMC ivith copper ions and the depression of ACMC on CuSO4-ac-tivated stibnite. The results of XPS and IR analyses show that after CMC is treated by aqueous ammonia , amino-carboxyl groups form in CMC molecules by H-bonding action ivhich can complex selectively ivith copper ions to form copper-amino-carboxylmethyl cellulose. On the surface of CuSO4-activated stibnite, ACMC is also able to complex strongly with cop-per ions and forms a strong hydrophilic depression film. Because there are the obvious difference of reactions between ACMC ivith Cu2+ and ACMC ivith Hg2+ , the separation of cinnabar from stibnite is successfully realized using ACMC as depressant and CuSO4 as activator.
文摘The Knoevenagel reaction of aromatic aldehydes with malononitrile and ethyl cyanoacetate proceeds smoothly in the presence of carboxymethyl cellulose supported triethylenetetramine as catalyst in the 95% ethanol to afford the desired E-isomers of the corresponding alkenes in yield of 74%~96% and good purity. The results confirm that the catalyst can offer definite advantages of good activity , easy separation, mild reaction condition and high yields. Moreover, it can be reused for not less than 5 runs.
文摘Under the condition of microwave radiation the carboxylmethyl starch(CMS)was prepared with solid phase synthesis method.The degree of substitution and viscosity of CMS was affected by radiation time,the volume of sodium hydroxide and water.The cleaning-aid property of CMS was studied,and compared with that of the traditional synthesis ways.
文摘The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole (Ag-CMCTS-TBZ) prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.