Phosphorus (P) and potassium (K) are non-renewable materials and </span><span style="font-family:Verdana;">widely</span><span style="font-family:Verdana;"> in many industrie...Phosphorus (P) and potassium (K) are non-renewable materials and </span><span style="font-family:Verdana;">widely</span><span style="font-family:Verdana;"> in many industries such as </span><span style="font-family:Verdana;">agricultural</span> <span style="font-family:Verdana;">sectors</span><span style="font-family:Verdana;">. On the other hand, the demand </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> P and K as fertilizers increases which following </span><span style="font-family:Verdana;">global</span><span style="font-family:Verdana;"> population. </span><span><span style="font-family:Verdana;">The nutrient source of P and K which get from biomass waste <i></span><i><span style="font-family:Verdana;">i.e.</i></span></i><span style="font-family:Verdana;"> incinerated </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> activated sludge and coffee husk biochar, respectively. The present study was conducted recovery of P and K as struvite-K (KMgPO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">·6H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O) precipitates. The results showed that alu</span></span><span><span style="font-family:Verdana;">minium was released simultaneously with P from incinerated activated sludge with precipitate of Al:P of 1:1, K:P of 0.5, and Mg:P of 3. However, aluminium was inhibited to form struvite-K. Then, we examined cation removal especially for removed Al by dissolved 0.5 M HNO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> and the solution was mixed with KH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">PO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and MgCl</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">·6展开更多
Methane adsorption by different forms of activated carbon obtained from coffee husks, including monolith honeycomb and disc types, was studied by activation with zinc salts and potassium hydroxide at 298.15 K and 303....Methane adsorption by different forms of activated carbon obtained from coffee husks, including monolith honeycomb and disc types, was studied by activation with zinc salts and potassium hydroxide at 298.15 K and 303.15 K and pressures up to 30.00 atm in a volumetric adsorption apparatus. We observed increased methane adsorption capacity on a mass basis in the different activated carbon monoliths with increasing surface area, total pore volume and micropore volume, with the honeycomb type displaying the highest methane absorption capacity. The maximum volumetric methane uptake by the synthesised carbon monoliths was observed to be 130 V/V at 298.15 K and 30.00 atm for honeycomb monoliths synthesised with zinc chloride (ZnCl2) and Polyvinyl alcohol (PVA) as the binder. Adsorption calorimetry results were used to describe the interaction between guest molecules and the adsorbent at low surface coverage and the energetic heterogeneous surface nature of the adsorbent.展开更多
In this work, Coffee husk (CH) was used as a solid phase extractor (SPE) for removal and/or minimization of Zn2+ and Ni2+ ions in aqueous media. XRD, FESEM and FTIR analysis of the SPE were performed for surface morph...In this work, Coffee husk (CH) was used as a solid phase extractor (SPE) for removal and/or minimization of Zn2+ and Ni2+ ions in aqueous media. XRD, FESEM and FTIR analysis of the SPE were performed for surface morphology and function groups characterisation. Batch mode adsorption studies were performed by varying the operational parameters such as adsorbent dose, solution pH, initial analyte concentration and contact time. The equilibrium data of both analytes was found a better fit with the Langmuir and Freundlich isotherm models. The qm of Langmuir for Zn2+ and Ni2+ ions were 12.987 and 11.11 mg/g, respectively. The adsorption capacities of the CH adsorbent towards Zn2+ and Ni2+ resulted of 12.53 and 10.33 mg/g, respectively. In addition, the kinetic data of Zn2+ and Ni2+ ions uptake revealed that the present system fitted well with pseudo-second-order kinetic model (R2 > 0.99). Thermodynamic studies showed that the retention step was exothermic, and spontaneous in nature. The results indicated that the coffee husk provides an effective and economical approach in highly reducing or almost eradication of both metals Zn2+ and Ni2+ from the aqueous solution.展开更多
文摘Phosphorus (P) and potassium (K) are non-renewable materials and </span><span style="font-family:Verdana;">widely</span><span style="font-family:Verdana;"> in many industries such as </span><span style="font-family:Verdana;">agricultural</span> <span style="font-family:Verdana;">sectors</span><span style="font-family:Verdana;">. On the other hand, the demand </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> P and K as fertilizers increases which following </span><span style="font-family:Verdana;">global</span><span style="font-family:Verdana;"> population. </span><span><span style="font-family:Verdana;">The nutrient source of P and K which get from biomass waste <i></span><i><span style="font-family:Verdana;">i.e.</i></span></i><span style="font-family:Verdana;"> incinerated </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> activated sludge and coffee husk biochar, respectively. The present study was conducted recovery of P and K as struvite-K (KMgPO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">·6H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">O) precipitates. The results showed that alu</span></span><span><span style="font-family:Verdana;">minium was released simultaneously with P from incinerated activated sludge with precipitate of Al:P of 1:1, K:P of 0.5, and Mg:P of 3. However, aluminium was inhibited to form struvite-K. Then, we examined cation removal especially for removed Al by dissolved 0.5 M HNO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> and the solution was mixed with KH</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">PO</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and MgCl</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">·6
文摘Methane adsorption by different forms of activated carbon obtained from coffee husks, including monolith honeycomb and disc types, was studied by activation with zinc salts and potassium hydroxide at 298.15 K and 303.15 K and pressures up to 30.00 atm in a volumetric adsorption apparatus. We observed increased methane adsorption capacity on a mass basis in the different activated carbon monoliths with increasing surface area, total pore volume and micropore volume, with the honeycomb type displaying the highest methane absorption capacity. The maximum volumetric methane uptake by the synthesised carbon monoliths was observed to be 130 V/V at 298.15 K and 30.00 atm for honeycomb monoliths synthesised with zinc chloride (ZnCl2) and Polyvinyl alcohol (PVA) as the binder. Adsorption calorimetry results were used to describe the interaction between guest molecules and the adsorbent at low surface coverage and the energetic heterogeneous surface nature of the adsorbent.
文摘In this work, Coffee husk (CH) was used as a solid phase extractor (SPE) for removal and/or minimization of Zn2+ and Ni2+ ions in aqueous media. XRD, FESEM and FTIR analysis of the SPE were performed for surface morphology and function groups characterisation. Batch mode adsorption studies were performed by varying the operational parameters such as adsorbent dose, solution pH, initial analyte concentration and contact time. The equilibrium data of both analytes was found a better fit with the Langmuir and Freundlich isotherm models. The qm of Langmuir for Zn2+ and Ni2+ ions were 12.987 and 11.11 mg/g, respectively. The adsorption capacities of the CH adsorbent towards Zn2+ and Ni2+ resulted of 12.53 and 10.33 mg/g, respectively. In addition, the kinetic data of Zn2+ and Ni2+ ions uptake revealed that the present system fitted well with pseudo-second-order kinetic model (R2 > 0.99). Thermodynamic studies showed that the retention step was exothermic, and spontaneous in nature. The results indicated that the coffee husk provides an effective and economical approach in highly reducing or almost eradication of both metals Zn2+ and Ni2+ from the aqueous solution.
