Effect of Attapulgite Pore Size Distribution on Soybean Oil Bleaching

Abstract

The pore size distribution and specific surface area of the attapulgite is a crucial parameter for the uptake of pigments of oil. Bleaching of the soybean oil with three attapulgites with different pore size distribution, which were assigned a, b, and c, respectively was investigated. The specific surface area and the pore size distribution of the attapulgites were characterized. The Freundlich isotherm analysis was used to evaluate the sorption capacity of the three attapulgite. Sample b gave the highest surface area and sample c the lowest. Sample b exhibited a wider pore distribution (8-65 Å ) whereas samples a and c had more micropores smaller than 15 Å . Sample a, in contrast to samples b and c, was characterized by some larger pores (100-170 Å ). The sorption capacity followed the sequence: attapulgite sample c > attapulgite sample a > attapulgite sample b. The sorption capacity was decided by the pore size distribution. The more pores with a distribution range 8-32 Å (i.e., close to the diameter of the pigments), the more pigments were removed. The attapulgite sample c, which had most pores (8-32 Å ) was the best.

Effects of Palygorskite Inclusion on the Growth Performance, Meat Quality, Antioxidant Ability, and Mineral Element Content of Broilers

“…The results obtained in the current study were consistent with findings of Chalvatzi et al [11] in which laying hens given diets supplemented with 1.0 % palygorskite for 24 weeks produced eggs with significantly lighter eggshell and yolk color. Most of the variation in meat color of normal meat quality can be explained by the pigment content, myoglobin forms, and internal reflectance [6], which in turn suggested that the reduced meat color (yellowness and redness) observed in this study may be due to the affinity between palygorskite and pigments [13,41].…”

“…Activated clays including palygorskite, sepiolite, and bentonite are the popular adsorbents for decolorization of edible oil due to their less expensive price than activated carbon and high specific area and adsorption capacity [13,[38][39][40][41]. In poultry, Blair et al [9] noted that laying hens fed diets supplemented with spent bleaching clay, a bentonite product from canola oil refining, had reduced yolk color.…”

“…The color of egg yolks mainly originates from yellow (e.g., lutein, zeaxanthin, apo-ester) and red (e.g., canthaxanthin, citraxanthin, astaxanthin) carotenoids or xanthophylls in the diets [8]. However, clay supplementation including palygorskite to the laying hen diet can induce the reduced yolk color [9][10][11], and it is most likely due to their affinity for pigments [12,13], suggesting that clay supplementation would decrease the accumulation of pigments in yolk. Most of the variation (86-90 %) in lightness, redness, and yellowness, chroma (saturation) and hue angle of pork of normal meat quality could be explained by the pigment content, myoglobin forms, and internal reflectance [6].…”

Kinetics and thermodynamics of β-carotene and chlorophyll adsorption onto acid-activated bentonite from Xinjiang in xylene solution

“…Furthermore, the adsorption amount of ␤-carotene was clearly high as compared with that of chlorophyll under the same adsorption conditions. This may be attributed to the smaller molecular size and chain structure conformation, ␤-carotene molecules, with little space resistance, are easier to adsorb on the surface of AAB or diffuse into the pores of AAB, because their molecular size is 2.1 nm × 0.8 nm × 0.7 nm as compared to the larger molecular size of chlorophyll (3.0 nm × 1.7 nm × 1.3 nm) and net structure of chlorophyll [25].…”

Photo degradation of methyl orange by attapulgite–SnO2–TiO2 nanocomposites

“…Another promising material for these systems is clay or a clay-based matrix, which is chemically inert, resistant to deterioration, commercially available in large quantities and has many industrial, catalytic and environmental applications [19][20][21][22][23][24][25] or fibrous morphology, is characterized by a porous crystalline structure containing tetrahedral layers alloyed together along longitudinal sideline chains [26]. Due to its unique structure and considerable textual properties, natural ATT has been widely used as adsorbents, adhesives, catalysts and as catalyst supports [27][28][29][30][31][32][33]. Zhao [29,32] prepared silver and copper modified ATT/TiO 2 photocatalysts by a hydrolysis method, which exhibited much higher activity than that of the pure TiO 2 for the degradation of methylene blue.…”