This study systematically established the most effective refining process for Moringa oleifera (MO) kernel oil. Acid degumming (20.33 ± 1.37 ppm) removed significantly greater phosphorus than water degumming (31.18 ± 0.90 ppm). Neutralization was more effective than deodorization in decreasing the acid (0.06 mg KOH/g) and p-Anisidine (p-AV, 0.36 ± 0.03) values of the oil. Besides improving its color properties, acid-activated bleaching earth Type B was better than Types A and C in decreasing the oil’s p-AV (0.43 ± 0.02), acid value (3.96 ± 0.02 mg KOH/g), and moisture content (0.01 ± 0.00% w/w). The selected refining stages successfully produced MO kernel oil with acceptable peroxide value (PV, 1.66−3.33 meq/kg), p-AV (1.05−1.49), total oxidation value (TOTOX, 4.38−8.15), acid value (0.03 mg KOH/g), moisture content (0.01% w/w), phosphorus content (1.28−1.94 ppm), iodine value (80.79−81.03), oleic acid (79.52−79.65%), and tocopherol content (65.26−87.00 mg/kg).

We assess the technoeconomic feasibility of onsite electricity and steam generation from recovered low-grade thermal energy in oil refineries using organic Rankine cycle (ORC) engines and mechanical vapour compression (MVC) heat pumps in various countries. The efficiencies of 34 ORC and 20 MVC current commercial systems are regressed against modified theoretical models. The resulting theoretical relations predict the thermal efficiency of commercial ORC engines within 4−5% and the coefficient of performance (COP) of commercial MVC heat pumps within 10−15%, on average. Using these models, the economic viability of ORC engines and MVC heat pumps is then assessed for 19 refinery streams as a function of heat source and sink temperatures, and the available stream thermal energy, for gas and electricity prices in selected countries. Results show that: (i) conversion to electrical power with ORC engines is, in general, economically feasible for heat-source temperatures >70 °C, however with h... [more]

Antimony is classified as a critical/strategic metal. Its primary production is predominated by China via pyrometallurgical routes such as volatilization roasting—reduction smelting or direct reduction smelting. The performance of most of the pyro-processes is very sensitive to concentrate type and grade. Therefore, technology selection for a greenfield plant is a significant and delicate task to maximize the recovery rate of antimony and subsequently precious metals (PMs), mainly gold, from the concentrates. The current paper reviews the conventional pyrometallurgical processes and technologies that have been practiced for the treatment of antimony concentrates. The blast furnace is the most commonly used technology, mainly because of its adaptability to different feeds and grades and a high recovery rate. In addition, several other more environmentally friendly pyrometallurgical routes, that were recently developed, are reviewed but these are still at laboratory- or pilot-scales. For... [more]