Potential of garnet sand as an unconventional resource of the critical high-technology metals scandium and rare earth elements

Scandium is a critical raw material that is essential for the EU economy because of its potential application in enabling technologies such as fuel cells and lightweight materials. As there is currently no secure supply of Sc, several projects worldwide evaluate potential Sc sources. While elsewhere in Europe emphasis is placed upon secondary resources such as red mud, we investigated the potential of industrial garnet sand and its waste products. Since Sc readily substitutes for Mg and Fe in the crystal lattice of garnet, the garnet minerals almandine and pyrope, in particular, may show high Sc concentrations. Garnet sand, after being used as an abrasive in the cutting and sandblasting industry, is recycled several times before it is finally considered waste which eventually must be disposed of. Extraction of Sc (and rare earth elements, REE) from such garnet sand may generate added value and thereby reduce disposal cost. The studied garnet sands from different mines in Australia, India and the U.S., and industrial garnet sands commercially available in Germany from different suppliers show average Sc concentrations of 93.7 mg/kg and 90.7 mg/kg, respectively, i.e. similar to red mud. Our data also show that “fresh” and recycled garnet sands yield similar Sc concentrations. Within the framework of a minimum-waste approach, it may be feasible to utilize the industrial waste-product “garnet sand” as an unconventional source of Sc and REE, that reduces disposal cost.

Polyhydroxybutrate Production Using Groundnut Shell as Substrate by Bacillus circulans (MTCC 8167)

Groundnut shell is considered to agro-industrial waste product and is rich in lignocellulose materials. It is obtained after the removal of groundnut seed from its pod and used as fodder for cattle. Duc et al., (2019) elaborately reviewed beneficial uses groundnut shells for commercial and industrial purposes and listed production of various bio-products such as biodiesel, bioethanol, and nano-sheet. The aim of this work was to study the production of polyhydroxy butyrate (PHB) using groundnut shells as the carbon source after hydrolysate. Groundnut shell was pre-treated with alkaline reagent with 0.5M, 1M, and 1.5M, of potassium hydroxide and acid hydrolysis with 30%, 50%, and 70%, of sulphuric acid. Combined alkali (1M of potassium hydroxide) and acid (70% sulphuric acid) pre-treatment of groundnut shell yield maximum reducing sugar. In addition, with pre-treated groundnut shell, various pH level (6, 7, & 8), KH2PO4 (100mg/l, 200mg/l and 300mg/l), and temperature (250C, 300C and 350C) are also test for PHB production. Bacillus circulans (MTCC 8167) significantly utilized the hydrolysate substrate and produced the maximum amount PHB (7.6 ± 0.2 g L-l) with pH level 7 and 300C with 100mg/l of KH2PO4. A detailed study of the functional group was also done using FTIR and NMR. Through biochemical pre-treatment, an in-expensive groundnut shell was converted into a valuable bio-product in order to achieve the minimum waste production.

Qualitative and Quantitative Evaluation of Heat-Induced Changes in Polyphenols and Antioxidant Capacity in Prunus domestica L. By-products

Plum pomace, an agro-industrial waste product has received attention due to the worldwide popularity of plums. During convection, the content of flavan-3-ols decrease, except drying at 90 °C, whereas the content of i.e. chlorogenic, 3-p- and 4-p-coumaroylquinic acids, quercetin rutinoside, and galactoside was observed to increase along with the increase in process temperature. The highest content of all identified polyphenols was found in plum pomace powders obtained using a combination of convective at 90 °C and microwave vacuum drying (MVD) at 120 W, whereas the highest retention of the group consisted of phenolic acids, flavonols, and anthocyanins was noted when CD 70 °C/MVD 120 W was used, pointing to a strong influence of the type of polyphenols on their changes caused by drying. The correlations between TEAC ABTS and the sum of flavonoids (r = 0.634) and anthocyanins (r = 0.704) were established. The multiple regression analysis showed that polyphenol content was more strongly affected by drying time than by maximum temperature, whereas antioxidant capacity was more influenced by maximum temperature of sample than by drying time.

Spent turmeric reduces fat mass in rats fed a high-fat diet

The industrial waste product spent turmeric remarkably reduced obesity in rats fed a high-fat diet. The mesentery adipocyte' size in rats fed a STP diet was smaller than that in rats fed a control diet with or without antibiotic cocktail.

The Influence of Aluminium Dross on Cement Paste's Porosity

In this study aluminium dross, an industrial waste product from the aluminum casting industry which contains mostly aluminum, aluminium oxide, and volatile gases such as ammonia (NH3), methane (CH4) and hydrogen (H2). In this study it is used as an admixture in cement paste to observe its effects on the porosity and bulk density of the material. The parameters used in the study include; the effects when different quantities of aluminium dross are added to portland cement (portland cement:aluminium dross by weight; 1: 0.05, 1: 0.10, and 1: 0.20) and the effect of different sized particles of aluminium dross (average diameter of aluminium dross particles; <45, 60, and 90 μm) on porosity and bulk density of cement paste. According to the study, as the amount of aluminium dross content in cement paste increases, the area fraction of porosity in the cement paste increases; yet the bulk density of cement paste decreases. In addition, when the particle size of aluminium dross decreases both of the pores size in the cement paste and bulk density of cement paste decrease.