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Removal of Caramel Colours from Suger Beet Molasses and its Characteristics and Application in food Industry
J. Keramt, S. Malek,
Volume 5, Issue 1 (4-2001)
Abstract

Molasses are produced in large amounts by sugar cane and sugar beet factories every year. However, they are considered as the waste product of the crystallization plants. Thus, although they contain significant amounts of materials with deep black colour which can be separated as food colour, molasses are very cheap and feasible to be used for this purpose. Aliquots of diluted molasses, after adjusting the pH, were passed through the column followed by extraction with acidified alcohol. The highest yield of extraction (76.3%) was obtained by using diluted molasses (10° BX) and 150 ml of Amberlite resins. The solvent was removed and the solid colour was obtained by evaporating the water using a freeze drying system.

 The colour was characterized by determining its solubility, amount of ash, and sugar content and its colouring ability. Also, the stability of the colour under different conditions of acidic pH, temperature, and visible light was investigated. In addition, the colour values of the colour solution were measured by Hunter lab system.

The colour was compared with the imported caramel which is used in the black soft drinks of Zam Zam. Both had almost the same values of λmax. Also, their sensitivities to pH changes were similar. Samples of soft drinks made by using the prepared colour were compared with those made by caramel under different conditions of storage such as temperature and light. On the whole, the colour was found to be a very suitable replacement for caramel in the production of black soft drinks.

 Also the colour was used as partial replacement for cocoa powder in making chocolate milk. The taste panel showed that cocoa powder can be replaced by the colour powder by 20% with almost no detectable differences. The caramel from molasses is safe and can be used as a food colour. The cost of production was estimated at about 10 Rials per gram of caramel. Thus, from an economical point of view, industrial production of caramel from molasses is profitable.


Dyeing Wastewater Treatment Using a Batch Electrocoagulation System and Investigating the Effect of Retention Time and Electrode Distance on Removal Efficiency
S. Rezaei, M. Heidarpour, A. Aghakhani,
Volume 29, Issue 2 (7-2025)
Abstract
The growing concern for environmental protection and increasing demand for green approaches to address environmental problems have prompted researchers to explore a sustainable and reliable method for treating dyeing wastewater. One of the sustainable and reliable methods is the electrocoagulation process. In this study, a batch electrocoagulation reactor was designed to evaluate the efficiency of this process in treating dyeing wastewater. The effects of two parameters, electrode distance and retention time, on pollutant removal efficiency were investigated. Electrode distances of 2, 5, and 7 cm were tested, and retention times of 10, 15, 20, 25, and 30 minutes were examined. Results indicated that the optimal electrode distance was 5 cm and the optimal retention time was 20 minutes. Under these conditions, the removal efficiency of BOD, COD, TSS, color, and turbidity reached 83%, 85%, 98%, 98%, and 93%, respectively. The results of this research demonstrate the significant potential of the electrocoagulation system for treating dyeing wastewater.

Using Clinoptilolite Natural Zeolite in the Removal of Methylene Blue and Disperse Red 60 from Aqueous Solutions.
Noroullah Mirghaffari, Mohsen Soleimani, Azita Tayebi,
Volume 30, Issue 1 (3-2026)
Abstract
As the industry expands and water resources decline, attention has increasingly focused on the treatment and recycling of wastewater generated by various industrial processes. Adsorption using cost-effective and readily available adsorbents is a simple and low-cost method for wastewater treatment in various industrial sectors. In this study, clinoptilolite natural zeolite (CNZ) was employed for the removal of two dye pollutants: cationic methylene blue and disperse red 60. To evaluate the efficiency of CNZ, four variables, pH, contact time, adsorbent dosage, and initial dye concentration, were investigated using response surface methodology. Based on the results obtained from batch experiments, the maximum removal efficiencies of methylene blue and disperse red 60 by CNZ were 98.9% and 78.7%, respectively. These optimal removal percentages were achieved under the following conditions: a contact time of 120 minutes, an initial dye concentration of 50 mg/L, an adsorbent dosage of 20 g/L, and a pH of 10 for methylene blue and a pH of 4 for disperse red 60. The pseudo-second-order kinetic model, with an R² value greater than 0.90, exhibited the best fit for the adsorption of both dyes from aqueous solutions. Furthermore, the extent of dye adsorption exhibited a better correlation with the Langmuir (Disperse Red 60) and the Freundlich (Methylene Blue) adsorption isotherms. Results of column experiments demonstrated that the maximum adsorption capacities for Methylene Blue and Disperse Red 60 were 97.7 and 45.9 mg/g, respectively. The results revealed the high potential of CNZ as a sorbent for cationic dye pollutants from industrial wastewaters.
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