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Research paper thumbnail of The Use of Agricultural Waste in Solving of Environmental Problems in Democratic Republic of the Congo

The presence of chromium in wastewaters produced from mining industries in Democratic Republic of... more The presence of chromium in wastewaters produced from mining industries in Democratic Republic of the Congo is harmful for the environment. As a promising and polishing method for heavy metals removal from wastewaters, adsorption has been used with agricultural waste as low adsorbent. In this study, the use of sugar beet pulp has been investigated for the removal of hexavalent chromium from aqueous in batch adsorption mode. Adsorption experiments were conducted to obtain the optimal conditions combinations for the highest percent removal. Four parameters were studied such as contact time (30-180min), initial chromium concentration (10-50mg/L), pH (2-9) and solid to liquid ratio (0.25 g/100 mL-3 g/100 mL). However, the agitation rate was equal to 100 rpm and the room temperature was considered. The highest percent removals of 90.53% for 10 ppm concentration and 76.34% for 50 ppm concentration were achieved at the following conditions: pH 2, contact time 90 min, S/L ratios of 2 g/100 mL and 3 g/100 mL respectively. Langmuir and Freundlich adsorption isotherms were used for the mathematical description of adsorption equilibrium. Freundlich isotherm fitted well the equilibrium data. The maximum capacity (Q max) from the Langmuir isotherm was found to be 11.299 mg/g. These results indicated that sugar beet pulp can be used as low cost adsorbent for the removal of chromium from mining industries wastewater to avoid environmental problems.

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Research paper thumbnail of Agricultural Waste Can Solve Environmental Problems in Democratic Republic of the Congo

The industrial mining factories in Democratic Republic of the Congo (D.R.C.) discharge effluents ... more The industrial mining factories in Democratic Republic of the Congo (D.R.C.) discharge effluents containing hexavalent chromium and this situation can be very harmful to the environment. So the hexavalent chromium contained in wastewater should be removed in order to prevent environmental problems. Therefore, the present work aims to investigate the use of sugar beet pulp available in D.R.C. for the removal of hexavalent chromium from wastewater. Variables studied were chromium initial concentration (10–50mg/L), pH (2–9), solid/liquid ratio (0.25/100–3/100), and contact time (30–180min). All the experiments were performed at room temperature and average results were reported. The highest percent removals for 10 ppm concentration (90.53%) and 50 ppm concentration (76.34%) were achieved at the following conditions: pH 2, contact time 90 min, and solid/liquid ratios of 2 g/100mL and 3 g/100mL respectively

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Research paper thumbnail of The Use Of Agricultural Waste In Solving Of Environmental Problems In Democratic Republic Of The Congo

International Journal of Progressive Sciences and Technologies, 2022

The presence of chromium in wastewaters produced from mining industries in Democratic Republic of... more The presence of chromium in wastewaters produced from mining industries in Democratic Republic of the Congo is harmful for the environment. As a promising and polishing method for heavy metals removal from wastewaters, adsorption has been used with agricultural waste as low adsorbent. In this study, the use of sugar beet pulp has been investigated for the removal of hexavalent chromium from aqueous in batch adsorption mode. Adsorption experiments were conducted to obtain the optimal conditions combinations for the highest percent removal. Four parameters were studied such as contact time (30-180min), initial chromium concentration (10-50mg/L), pH (2-9) and solid to liquid ratio (0.25 g/100 mL-3 g/100 mL). However, the agitation rate was equal to 100 rpm and the room temperature was considered. The highest percent removals of 90.53% for 10 ppm concentration and 76.34% for 50 ppm concentration were achieved at the following conditions: pH 2, contact time 90 min, S/L ratios of 2 g/100 mL and 3 g/100 mL respectively. Langmuir and Freundlich adsorption isotherms were used for the mathematical description of adsorption equilibrium. Freundlich isotherm fitted well the equilibrium data. The maximum capacity (Q max) from the Langmuir isotherm was found to be 11.299 mg/g. These results indicated that sugar beet pulp can be used as low cost adsorbent for the removal of chromium from mining industries wastewater to avoid environmental problems.

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Research paper thumbnail of Modeling and Optimization of Manganese Carbonate Precipitation Using Response Surface Methodology

Journal of Engineering and Exact Science, 2021

Ca 2+ foi usada para realizar a recuperação máxima de manganês e a recuperação mínima de magnésio... more Ca 2+ foi usada para realizar a recuperação máxima de manganês e a recuperação mínima de magnésio. A precipitação de carbonato foi usada devido à melhor seletividade do manganês sobre o magnésio e a recuperação de outras impurezas em comparação com a precipitação de hidróxido. Quatro fatores foram estudados: valor do pH da solução, tempo de contato, temperatura de reação e consumo de carbonato de sódio. Análise de variância (ANOVA) e metodologia de superfície de resposta (RSM) foram usadas para determinar o ótimo. Nas condições ótimas, as recuperações de manganês e magnésio foram as mais altas e as mais baixas, respectivamente, enquanto o pH, o tempo, a temperatura e o volume de Na2CO3 foram os mais baixos. Os valores dos quatro fatores foram encontrados da seguinte forma: 8,9293, 60,69 min, 77,95°F e 50,7650 mL, respectivamente. Além disso, as recuperações de manganês e magnésio foram de 99,9799% e 4,3045%, respectivamente. Os resultados mostram que a otimização usando RSM é eficaz na melhoria da precipitação de carbonato de manganês.

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Research paper thumbnail of Influence of Lead Nitrate on Sulfurizing Flotation of a Copper-Cobalt Oxide Ore

Walailak Journal of Science and Technology, 2021

Copper-cobalt oxide ores contain several minerals that are economically treatable by concentratio... more Copper-cobalt oxide ores contain several minerals that are economically treatable by concentration techniques. The most used technique is froth flotation in which selective reagents are used to recover more valuables. It is, therefore, important to examine the optimal doses of those reagents while investigating the behaviors of minerals at the same time. This study explored the influence of lead nitrate Pb(NO 3) 2 on the froth flotation of oxide ore to increase valuable metals recoveries. Four factors were investigated including Pb(NO 3) 2 dosage, its conditioning, its addition dose in the 2 nd fraction, and sulfidiser dosage. Other parameters were kept constant. The optimum was found at 25 g/t of Pb(NO 3) 2 , conditioning together with sodium silicate (Na 2 SiO 3) for 5 min, the addition of 5 g/t of Pb(NO 3) 2 in the 2 nd fraction, and 3,000 g/t of sulfidiser. Recoveries in concentrates were 79.51 % Copper (Cu) and 60.27 % Cobalt (Co), with grades of 9.49 and 0.67 %, respectively. The conclusion was that the use of Pb(NO 3) 2 can considerably improve copper and cobalt recoveries.

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Research paper thumbnail of Comparative Cleaning Stages in Recovery of Copper and Cobalt from Tailings using Potassium Amylxanthate as Collector

EJERS, 2021

Copper and cobalt demand is projected to be increased from here to 2050 and the challenge is to f... more Copper and cobalt demand is projected to be increased from here to 2050 and the challenge is to find treat economically minerals which contains those metals. Several tailings from oxide ores throughout the word contain good grades of copper and cobalt that should be recovered by froth flotation. This paper investigates the recovery of copper and cobalt through reprocessing of spiral classifier tailings by determination of specific reagents dosage. The flotation behaviours of malachite and heterogenite were studied through many roughing and cleaning flotation tests in order to recovery most of copper and cobalt. The effect of specific reagents was be varied and others parameters were kept constant. The highest recoveries of both copper and cobalt in rougher concentrate were respectively 82.51% and 72.51% with grades of 12.52% and 0.99% respectively. However, the cleaner concentrate was 24.54 Cu% and 1.38% Co with recoveries of 69.26 % and 40.7% respectively. It was concluded that the reprocessing of spiral classifier tailings through froth flotation is benefit because it recovers most of desired metal and reduces the risk of their presence on environment through plant tailings. Recycling of cleaner tailings was also proposed.

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Research paper thumbnail of Recovery of copper and cobalt in the comparative flotation of a sulfide ore using xanthate and dithiophosphate collectors

IJEAS, 2019

 Abstract-Copper and cobalt are two major metals used in industry. They play a role in widely ma... more  Abstract-Copper and cobalt are two major metals used in industry. They play a role in widely many domains like that electricity, chemistry and electrochemistry. They are contained into several minerals like chalcopyrite, carrolite, chalcocite, etc. associated to pyrite. The froth flotation and behaviors of chalcocite and carrolite were investigated through many flotation tests in order to recovery copper and cobalt. This paper investigates the effect of potassium amyl xanthate (PAX) and sodium dibutyl dithiophosphate (DANA) performance on both copper and cobalt recovery in single roughing flotation. The effect of pH on the flotation is proposed. Some parameters were kept constant such as particle size d80=75 μm, pulp density 10% solids, impeller speed 1300 rpm, and PAX doses of DANA (105 g/t per each) as collectors, dose of DF250 (5 drops) as frother, dose of Na 2 SiO 3 (200 g/t) as dispersant and depressant. Only the pulp pH was varied from the natural pH to 11, using Ca(OH) 2 as regulator. According to results, PAX (105 g/t) was found as the best collector for recovery of copper both at natural pH and pH=11. At natural pH, the concentrate was found at 16.1% copper recovery with a yield of 99.63%. At pH=11, the concentrate was found at 16.1% copper recovery with a yield of 99.05%. For the recovery of cobalt, DANA (105 g/t) was found better as the collector at natural pH producing a concentrate at 0.51% cobalt recovery yield of 76.48%. At pH=11, PAX (105 g/t) was found better as the collector. The concentrate was found at 0.91% cobalt with a recovery yield of 85.13%.

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Research paper thumbnail of The Use of Agricultural Waste in Solving of Environmental Problems in Democratic Republic of the Congo

The presence of chromium in wastewaters produced from mining industries in Democratic Republic of... more The presence of chromium in wastewaters produced from mining industries in Democratic Republic of the Congo is harmful for the environment. As a promising and polishing method for heavy metals removal from wastewaters, adsorption has been used with agricultural waste as low adsorbent. In this study, the use of sugar beet pulp has been investigated for the removal of hexavalent chromium from aqueous in batch adsorption mode. Adsorption experiments were conducted to obtain the optimal conditions combinations for the highest percent removal. Four parameters were studied such as contact time (30-180min), initial chromium concentration (10-50mg/L), pH (2-9) and solid to liquid ratio (0.25 g/100 mL-3 g/100 mL). However, the agitation rate was equal to 100 rpm and the room temperature was considered. The highest percent removals of 90.53% for 10 ppm concentration and 76.34% for 50 ppm concentration were achieved at the following conditions: pH 2, contact time 90 min, S/L ratios of 2 g/100 mL and 3 g/100 mL respectively. Langmuir and Freundlich adsorption isotherms were used for the mathematical description of adsorption equilibrium. Freundlich isotherm fitted well the equilibrium data. The maximum capacity (Q max) from the Langmuir isotherm was found to be 11.299 mg/g. These results indicated that sugar beet pulp can be used as low cost adsorbent for the removal of chromium from mining industries wastewater to avoid environmental problems.

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Research paper thumbnail of Agricultural Waste Can Solve Environmental Problems in Democratic Republic of the Congo

The industrial mining factories in Democratic Republic of the Congo (D.R.C.) discharge effluents ... more The industrial mining factories in Democratic Republic of the Congo (D.R.C.) discharge effluents containing hexavalent chromium and this situation can be very harmful to the environment. So the hexavalent chromium contained in wastewater should be removed in order to prevent environmental problems. Therefore, the present work aims to investigate the use of sugar beet pulp available in D.R.C. for the removal of hexavalent chromium from wastewater. Variables studied were chromium initial concentration (10–50mg/L), pH (2–9), solid/liquid ratio (0.25/100–3/100), and contact time (30–180min). All the experiments were performed at room temperature and average results were reported. The highest percent removals for 10 ppm concentration (90.53%) and 50 ppm concentration (76.34%) were achieved at the following conditions: pH 2, contact time 90 min, and solid/liquid ratios of 2 g/100mL and 3 g/100mL respectively

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Research paper thumbnail of The Use Of Agricultural Waste In Solving Of Environmental Problems In Democratic Republic Of The Congo

International Journal of Progressive Sciences and Technologies, 2022

The presence of chromium in wastewaters produced from mining industries in Democratic Republic of... more The presence of chromium in wastewaters produced from mining industries in Democratic Republic of the Congo is harmful for the environment. As a promising and polishing method for heavy metals removal from wastewaters, adsorption has been used with agricultural waste as low adsorbent. In this study, the use of sugar beet pulp has been investigated for the removal of hexavalent chromium from aqueous in batch adsorption mode. Adsorption experiments were conducted to obtain the optimal conditions combinations for the highest percent removal. Four parameters were studied such as contact time (30-180min), initial chromium concentration (10-50mg/L), pH (2-9) and solid to liquid ratio (0.25 g/100 mL-3 g/100 mL). However, the agitation rate was equal to 100 rpm and the room temperature was considered. The highest percent removals of 90.53% for 10 ppm concentration and 76.34% for 50 ppm concentration were achieved at the following conditions: pH 2, contact time 90 min, S/L ratios of 2 g/100 mL and 3 g/100 mL respectively. Langmuir and Freundlich adsorption isotherms were used for the mathematical description of adsorption equilibrium. Freundlich isotherm fitted well the equilibrium data. The maximum capacity (Q max) from the Langmuir isotherm was found to be 11.299 mg/g. These results indicated that sugar beet pulp can be used as low cost adsorbent for the removal of chromium from mining industries wastewater to avoid environmental problems.

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Research paper thumbnail of Modeling and Optimization of Manganese Carbonate Precipitation Using Response Surface Methodology

Journal of Engineering and Exact Science, 2021

Ca 2+ foi usada para realizar a recuperação máxima de manganês e a recuperação mínima de magnésio... more Ca 2+ foi usada para realizar a recuperação máxima de manganês e a recuperação mínima de magnésio. A precipitação de carbonato foi usada devido à melhor seletividade do manganês sobre o magnésio e a recuperação de outras impurezas em comparação com a precipitação de hidróxido. Quatro fatores foram estudados: valor do pH da solução, tempo de contato, temperatura de reação e consumo de carbonato de sódio. Análise de variância (ANOVA) e metodologia de superfície de resposta (RSM) foram usadas para determinar o ótimo. Nas condições ótimas, as recuperações de manganês e magnésio foram as mais altas e as mais baixas, respectivamente, enquanto o pH, o tempo, a temperatura e o volume de Na2CO3 foram os mais baixos. Os valores dos quatro fatores foram encontrados da seguinte forma: 8,9293, 60,69 min, 77,95°F e 50,7650 mL, respectivamente. Além disso, as recuperações de manganês e magnésio foram de 99,9799% e 4,3045%, respectivamente. Os resultados mostram que a otimização usando RSM é eficaz na melhoria da precipitação de carbonato de manganês.

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Research paper thumbnail of Influence of Lead Nitrate on Sulfurizing Flotation of a Copper-Cobalt Oxide Ore

Walailak Journal of Science and Technology, 2021

Copper-cobalt oxide ores contain several minerals that are economically treatable by concentratio... more Copper-cobalt oxide ores contain several minerals that are economically treatable by concentration techniques. The most used technique is froth flotation in which selective reagents are used to recover more valuables. It is, therefore, important to examine the optimal doses of those reagents while investigating the behaviors of minerals at the same time. This study explored the influence of lead nitrate Pb(NO 3) 2 on the froth flotation of oxide ore to increase valuable metals recoveries. Four factors were investigated including Pb(NO 3) 2 dosage, its conditioning, its addition dose in the 2 nd fraction, and sulfidiser dosage. Other parameters were kept constant. The optimum was found at 25 g/t of Pb(NO 3) 2 , conditioning together with sodium silicate (Na 2 SiO 3) for 5 min, the addition of 5 g/t of Pb(NO 3) 2 in the 2 nd fraction, and 3,000 g/t of sulfidiser. Recoveries in concentrates were 79.51 % Copper (Cu) and 60.27 % Cobalt (Co), with grades of 9.49 and 0.67 %, respectively. The conclusion was that the use of Pb(NO 3) 2 can considerably improve copper and cobalt recoveries.

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Research paper thumbnail of Comparative Cleaning Stages in Recovery of Copper and Cobalt from Tailings using Potassium Amylxanthate as Collector

EJERS, 2021

Copper and cobalt demand is projected to be increased from here to 2050 and the challenge is to f... more Copper and cobalt demand is projected to be increased from here to 2050 and the challenge is to find treat economically minerals which contains those metals. Several tailings from oxide ores throughout the word contain good grades of copper and cobalt that should be recovered by froth flotation. This paper investigates the recovery of copper and cobalt through reprocessing of spiral classifier tailings by determination of specific reagents dosage. The flotation behaviours of malachite and heterogenite were studied through many roughing and cleaning flotation tests in order to recovery most of copper and cobalt. The effect of specific reagents was be varied and others parameters were kept constant. The highest recoveries of both copper and cobalt in rougher concentrate were respectively 82.51% and 72.51% with grades of 12.52% and 0.99% respectively. However, the cleaner concentrate was 24.54 Cu% and 1.38% Co with recoveries of 69.26 % and 40.7% respectively. It was concluded that the reprocessing of spiral classifier tailings through froth flotation is benefit because it recovers most of desired metal and reduces the risk of their presence on environment through plant tailings. Recycling of cleaner tailings was also proposed.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Recovery of copper and cobalt in the comparative flotation of a sulfide ore using xanthate and dithiophosphate collectors

IJEAS, 2019

 Abstract-Copper and cobalt are two major metals used in industry. They play a role in widely ma... more  Abstract-Copper and cobalt are two major metals used in industry. They play a role in widely many domains like that electricity, chemistry and electrochemistry. They are contained into several minerals like chalcopyrite, carrolite, chalcocite, etc. associated to pyrite. The froth flotation and behaviors of chalcocite and carrolite were investigated through many flotation tests in order to recovery copper and cobalt. This paper investigates the effect of potassium amyl xanthate (PAX) and sodium dibutyl dithiophosphate (DANA) performance on both copper and cobalt recovery in single roughing flotation. The effect of pH on the flotation is proposed. Some parameters were kept constant such as particle size d80=75 μm, pulp density 10% solids, impeller speed 1300 rpm, and PAX doses of DANA (105 g/t per each) as collectors, dose of DF250 (5 drops) as frother, dose of Na 2 SiO 3 (200 g/t) as dispersant and depressant. Only the pulp pH was varied from the natural pH to 11, using Ca(OH) 2 as regulator. According to results, PAX (105 g/t) was found as the best collector for recovery of copper both at natural pH and pH=11. At natural pH, the concentrate was found at 16.1% copper recovery with a yield of 99.63%. At pH=11, the concentrate was found at 16.1% copper recovery with a yield of 99.05%. For the recovery of cobalt, DANA (105 g/t) was found better as the collector at natural pH producing a concentrate at 0.51% cobalt recovery yield of 76.48%. At pH=11, PAX (105 g/t) was found better as the collector. The concentrate was found at 0.91% cobalt with a recovery yield of 85.13%.

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