Comparative Study of Biogas Production from Jackfruit Waste, Banana Peels, and Pineapple Peels Co-Digested with Cow Dung

Only 42% of Uganda’s population has access to electricity. The population continues to use firewood and charcoal as a source of energy, which leads to depletion of forests thus to climate change. The purpose of this study was to assess the potential of biogas production from jackfruit waste, banana peels, and pineapple peels when co-digested with cow dung as an alternative energy source. Substrates for each waste were co-digested with varying proportions (0%, 25%, and 50%) of cow dung using laboratory-scale 250 mL anaerobic digestors. The total biogas generation for jackfruit waste, banana peels, and pineapple peels after 30 days of anaerobic digestion was 82.3, 189, and 262 mL, respectively. When jack fruit waste, pineapple peels and banana peels were co-digested with 25% cow dung, the total amount of biogas produced increased by a factor of two and three, respectively. However, 50% of cow dung only significantly (p ≤ 0.05) improved for jack fruit waste by two folds. Therefore, the results indicated that jackfruit waste, banana and pineapple peels can be used for biogas production to augment energy supply. .

Heavy metals adsorption by banana peels micro-powder: Equilibrium modeling by non-linear models

In this study the copper and lead adsorption efficiency onto banana peels powder was investigated. The agroindustrial waste recovery represents one of the Circular Economy pillars. In the view of the synthesis of an environmentally friendly adsorbent material, the powder was used without any preliminary chemical or thermal activation, but only after simple washing, drying and grinding. The bio-adsorbent was characterized by the FTIR technique and tested in batch mode on synthetic aqueous solutions containing Pb and Cu in the range 10–90 mg·L^(-1). A selection of two(Langmuir, Freundlich) and three(Sips, Redlich–Peterson, Koble–Corrigan) parameter isotherm models was chosen to fit adsorption equilibrium data by non-linear regression procedure. The best fit isotherm model was selected relying on the error function with the lowest average percentage error(APE) value, among those characterized by the highest R^2 values. As expected, the three-parameter models are found to better represent both metals bio-adsorption, with APE and R^2 values always lower and higher, respectively, than the corresponding values obtained for the two-parameter models.

Determination of the Antioxidant Potentials of Two Different Varieties of Banana Peels in Two Different Solvents

Fruit wastes which are perishable pose a big problem to pollution monitoring agencies;however these problems can be reduced by utilizing the high value compounds present in the food waste. Banana peels contain a reasonable number of antioxidant compounds such as gallocatechin and dopamine. This paper investigates the anti-oxidant potential of two different varieties of Banana peels (Dwarf cavandish and Musa omini). The peels were extracted with two different solvents (Methanol and Ethanol) using the soxhlet extractor. The results show that ethanolic extracts have higher phenolics and flavonoid contents (336.83 - 383.83 mgGAE/100g, 242.83 - 252.82 mgRutin/100g) compared to the methanolic extracts of the same banana varieties (299.42 - 344 mgGAE/100g, 240.77 - 241.23 mgRutin/100g). However methanolic extracts exhibit higher DPPH Antioxidants Activity (30.82% - 51.66%) compared to ethanolic extracts (25.44% - 30.27%). This implies that antioxidative compounds other than phenolics and flavonoids were also involved in inhibiting the DPPH Radicals. It was also observed that at any concentration between 0.5 - 2.5 mg, ethanol extracts of both dwarf cavandish and musa omini had higher reducing power than the other two varieties.

Characterizations of Banana Peel and its Efficiency for Copper Adsorption

This research described the chemical and physical characterizations of banana （Musa sapientum Linn） peel for adsorption of copper. The FT-IR spectroscopy, BET （surface area） and SEM （scanning electron microscopy） coupled with EDX （energy dispersive X-ray） analysis were used for characterizations, while copper concentration was determined by ICP spectroscopy. The different parameters： pH values 3.0 to 9.0, banana dose （0.1 g to 0.7 g） and adsorption times （30 min to 180 min） were investigated for studying an adsorption efficient. It was found that banana peel （0.1 g） was a bio-adsorbent for copper adsorption under the suitable conditions at pH 7.0 and 90 min adsorption time. The sorption pattern was additionally found to be in linear form, according to the Freundlich and Langmuir equations with R2 = 0.966 and 0.994, respectively.

Banana Peel for Acetylsalicylic Acid Retention

A method for adsorption involving banana peel (BP) was studied to remove the pollutant acetylsalicylic acid (ASA) in aqueous medium. The results show that bioadsorbent has satisfactory maximum adsorption capacity (2.29 mg/g) for removing this analgesic and anti-inflammatory drug in aqueous solution (pH 7.0) using the Langmuir mathematical model. The tested concentrations of this pollutant were higher than the levels commonly found in the aquatic environment. This and other results suggest the BP as an alternative to ASA removal in water contaminated with pharmaceuticals pollutants.

Preparation of Hierarchically Interconnected Porous Banana Peel Activated Carbon for Methylene Blue Adsorption

Hierarchically interconnected porous activated carbon have high specific surface areas, large numbers of dye adsorption sites, and interconnected pores for dye molecule diffusion and transportation. We prepared hierarchically interconnected porous banana peel activated carbons(BPACs) via a green method involving hydrothermal pretreatment and KOH activation, and systematically tested its methylene blue(MB) adsorption capacity. SEM showed that the BPACs had an interconnected porous structure and high-porosity surface. The Brunauer-Emmett-Teller surface area was 601.21 m^2/g, the adsorption average pore diameter was 2.11 nm, and the total pore volume was 0.32 cm^3/g. The MB adsorption capacity increased with increasing temperature, initial MB concentration, and pH value; it decreased with increasing adsorbent dosage. The adsorption isotherms and kinetic results for MB adsorption on BPACs were best described by the Langmuir adsorption and pseudo-second-order kinetic models, respectively. BPACs have a well-developed hierarchically interconnected porous structure, which increase the MB adsorption capacity and removal efficiency. Systematic MB adsorption tests show that BPAC is a highly efficient and easily available adsorbent.

Enhanced Biogas Production from the Anaerobic Batch Treatment of Banana Peels

Waste disposal management and the energy crisis are important challenges facing most countries.The fruit-processing industry generates daily several tons of wastes,of which the major share comes from banana farms.Anaerobic digestion(AD)technology has been applied to the treatment of wastewater,animal slurry,food waste,and agricultural residues,with the primary goals of energy production and waste elimination.This study examines the effect of organic loading(OL)and cow manure(CM)addition on AD performance when treating banana peel waste(BPW).The maximum daily biogas production rates of banana peels(BPs)with a CM content of 10%,20%,and 30%at 18 and 22 g of volatile solids(gvs)per liter were 50.20,48.66,and 62.78 mL (gvs.d)^-1 and 40.49,29.57,and 46.54 mL (gvs.d)^-1,respectively.However,the daily biogas yield showed no clear interdependence with OL or CM content.In addition,a kinetic analysis using first-order and cone models showed that the kinetic parameters can be influenced by the process parameters.

Well-dispersive K2O-KCl alkaline catalyst derived from waste banana peel for biodiesel synthesis

In this work, a novel alkaline catalyst was synthesized by an economical and effective method of roasting waste banana peel. From XRD, FTIR, SEM, EDS, TGA and CO2-TPD characterization, it was proved that the calcined banana peel catalyst showed the strong alkalinity and well dispersity in microstructure, and K2O-KCl as the main active contents. The calcined banana peel catalyst showed better catalytic performance than the catalysts by physical mixing of K2O and KCl, which was due to good dispersibility of K2O-KCl formed during decomposing of carbon fiber by calcination of banana peel. Furthermore, the calcined banana peel catalyst also performed well in both water-resistant ability and recyclability, indicating their potential for biodiesel production from an efficient, robust, and low-cost catalyst.

Banana Peel Carbon that Containing Functional Groups Applied to the Selective Adsorption of Au(III) from Waste Printed Circuit Boards

This paper reports a kind of banana peel carbon (BPC) containing -OH, -NH2 functional groups which prepared through controlling carbonization temperature and its application on the selective adsorption of gold from waste printed circuit boards (PCBs). The adsorption of BPC for Au(III) reached equilibrium in 30 min and the adsorption of Au(III) was favorable at pH 2.5. Meanwhile, the adsorption isotherm showed the maximum adsorption capacity of 801.7 mg/g for Au(III). The results displayed that BPC had a strong selectivity for Au(III) and a negligible affinity to base metal ions, such as Cu(II), Ni(II), Fe(III) and Pb(II). The BPC adsorbent, which absorbed gold, can be recovered completely by HCl-thiourea solution.

Probing nutritional and functional properties of salted noodles supplemented with ripen Banana peel powder

Banana peel is appreciated for higher dietary fiber, phenolics, flavonoid contents, and minerals (particularly iron, calcium, and potassium), despite being a waste product. After drying, it can be processed into powder/flour to be combined with wheat flour (WF) for development of value-added products. In this study, we substituted WF with banana peel powder (BPP) at supplementation rates of 5, 10, and 15%, and evaluated their suitability to develop salted noodles. The results showed that the composite flour with 15% BPP had significantly higher protein, ash, and crude fiber content as compared to control. Higher antioxidant capacity was observed in composite flour noodles: total phenolics content (TPC), total flavonoid content (TFC), ferric reducing power (FRAP) and DPPH reducing power were increased up to 278, 260, 143 and 13 percent respectively in the noodles containing 15% BPP as compared to control (100% WF). On the other hand, values for viscosity decreased up to 22% with addition of BPP in WF. Furthermore, water absorption capacity and cooking losses were increased up to 15 and 13 percent respectively with 15% BPP incorporation in WF. Results for sensory evaluation demonstrated that noodles with 10% BPP scored highest for sensory profile.

Antioxidant Potential of Peel Extracts of Banana Varieties (<i>Musa sapientum</i>)

The study has been aimed to evaluate and compare phytochemical content and the antioxidant activity in peel extracts of nine local varieties of banana, i.e. Musa sapientum species. Ethanolic extract of peels of these varieties were subjected to in vitro free radical scavenging assays like DPPH, ABTS and lipid peroxidation inhibition assay. Total antioxidant capacity assay to confirm the antioxidant potential and phytochemical content such as total phenols, flavonoids were also determined. The results obtained were analyzed statistically by ANOVA and DMRT analysis. The peel ex- tracts of all the nine varieties of banana exhibited significant antioxidant and phytochemical activities with Musa spp – Blueggoe (Monthan) - AAB and Musa spp – Rasthali – AAB showing highest free radical scavenging activity and Musa spp – Karpooravalli – ABB, Musa spp – Rasthali – AAB, Musa spp - Ney Poovan (Kadali) – AB and Musa spp – Mysore (Poovan) – AAB having highest phytochemical content. The study suggests that peel extracts of these banana varieties could be useful to combat free radical mediated diseases.

协同微波法提取香蕉皮果胶的工艺研究

以本地香蕉皮为原料,采用不同提取剂协同微波法提取果胶,分析果胶的产率及理化性质,结果显示六偏磷酸钠协同微波法来制备皮果胶得率和品质较好。以六偏磷酸钠提取剂协同微波提取香蕉皮果胶,通过单因素试验和正交法优选,确定了香蕉皮果胶提取的最优工艺条件。结果表明:加入0.6%含量的六偏磷酸钠螯合剂辅助微波法提取果胶的最佳工艺参数为:料液比为1∶12 g/mL、pH值为2、微波功率为800 W、微波时间为3 min,果胶提取率达10.15%。

香蕉果酒带皮发酵对其品质和挥发性香气成分的影响

为了探究香蕉皮对香蕉果酒品质和风味的影响,该研究对带皮香蕉果酒和去皮香蕉果酒发酵过程中糖度、酒精度、总酸和多酚等理化指标进行测定,同时利用气相色谱-质谱联用技术测定两种果酒中挥发性香气物质,结果显示带皮香蕉果酒的酒精度为10.5%vol,低于去皮香蕉果酒的12.3%vol,但是发酵结束后带皮香蕉果酒中总酸(4.03 g/L)和感官评分(87.62),要显著优于去皮香蕉果酒。此外,带皮香蕉果酒及其蒸馏酒中甲醇含量分别为120.20 mg/L和372.30 mg/L,远低于对应国家限量标准。挥发性风味物质分析结果显示香蕉酒中主要的风味物质为酯类和醇类,带皮香蕉果酒风味物质种类比去皮香蕉果酒更为丰富,其中乙酸乙酯(>8.10 mg/L)和3-甲基-1-丁醇(>15.78 mg/L)是香蕉果酒中主要的挥发性风味物质。因此香蕉皮的添加可以改善果酒品质和风味且不会显著提高果酒中甲醇的含量,但是对出酒率有一定的影响,该研究为实现食品原料的整体化综合利用、减少食品加工废弃物的生成拓宽了思路,同时也为开发高品质香蕉酒提供了参考。

大孔树脂纯化香蕉皮缩合单宁的吸附特性分析与工艺优化

为提高香蕉皮缩合单宁提取物纯度,提升其后续研究与利用价值,该研究采用大孔树脂吸附法纯化香蕉皮缩合单宁,通过比较6种大孔树脂的吸附与解吸性能,筛选出最适宜的树脂型号,并从动力学和热力学的角度分析该树脂对香蕉皮缩合单宁的吸附特性,探究其纯化工艺条件。结果表明:HP-20型大孔树脂是纯化香蕉皮缩合单宁的适宜树脂;静态吸附-解吸动力学试验表明HP-20树脂分别在8、5 h内能够完成对香蕉皮缩合单宁的吸附、解吸过程,该吸附过程符合伪二阶动力学方程(R^(2)=0.997 2);Freundlich热力学模型适用于解释树脂与缩合单宁间的相互作用,这是一种发生在多分子层表面的吸附,模型常数K_(F)与温度成正相关,表明升温利于吸附的进行;热力学参数计算结果为ΔG<0,ΔH=5.13 kJ/mol,ΔS=47.28 J/mol·K,进一步证明了该过程是自发的、吸热的过程,且物理吸附占据主导作用,无序性有所增加。较佳的纯化参数是上样浓度为6 mg/mL、上样流速为1.5 mL/min、上样量为200 mL、洗脱液乙醇浓度为70%、洗脱流速为1.5 mL/min、洗脱液用量为120 mL。经该条件纯化后,香蕉皮缩合单宁纯度由5.79%提高到68.44%。说明HP-20树脂和优化参数对香蕉皮缩合单宁的纯化效果良好。

不同颜色果袋套袋对宝岛蕉果实品质的影响

为了提高宝岛蕉果实商品性,开展蓝色(对照)、红色、黄色、透明聚乙烯(PE)果袋套袋处理,测定比较不同套袋处理的宝岛蕉果实色泽、果肉果皮硬度、货架期以及可溶性固形物含量等内在品质指标,并采用隶属函数法综合评价各处理。结果表明,透明PE袋、红色PE袋和黄色PE袋能显著提高青蕉果皮亮度。相比对照(蓝色PE袋),透明PE袋、红色PE袋和黄色PE袋均能显著提高熟蕉果皮硬度,黄色PE袋显著延长熟蕉果实货架期。相比其他处理,红色PE袋处理显著降低果实可溶性固形物含量,黄色PE袋降低果实总酸含量,且显著提高固酸比。综合评价发现黄色PE袋适宜作为宝岛蕉的套袋材料,可在生产上推广应用。

NaOH提取香蕉皮纤维对水中Pb^(2+)的吸附特性及机理研究

为探讨生物质纤维吸附材料对水中Pb^(2+)的吸附特性,以香蕉皮为原料,采用NaOH提取纤维吸附水中的Pb^(2+)。研究结果表明,在实验条件范围内,香蕉皮纤维对Pb^(2+)的理论饱和吸附量可达130.74 mg·g^(-1),远强于香蕉皮(57.44 mg·g^(-1)),其吸附平衡时间为90 min,低于香蕉皮粉末(120 min)。香蕉皮纤维对水中Pb^(2+)的吸附过程符合Langmuir等温模型和准二级动力学模型,拟合结果显示,香蕉皮粉末对Pb^(2+)的吸附亲和力较强。BET比表面积、扫描电镜、EDS能谱、傅里叶变换红外光谱表征结果表明,香蕉皮纤维较香蕉皮,其主要官能团结构未发生明显变化,但其表面形态和元素构成均发生了有利于Pb^(2+)吸附的变化。

废弃香蕉皮粉末对六价铬的吸附特性与机理研究

研究了废弃香蕉皮粉末对六价铬〔Cr(Ⅵ)〕的吸附特性与机理。重点考察各种影响因素,利用等温线、动力学和热力学方程定量分析了吸附过程,并采用扫描电镜(SEM)、红外光谱(FTIR)和X射线光电子能谱(XPS)等手段探讨了吸附机理。结果表明:香蕉皮粉末是一种优良的吸附剂,对Cr(Ⅵ)的吸附性能远高于其他生物质。香蕉皮粉末对Cr(Ⅵ)吸附的最佳pH值为2,吸附24 h时达到平衡,Cr(Ⅵ)初始浓度和温度越高,吸附效果就越好。3次吸附-解吸循环后,香蕉皮粉末对Cr(Ⅵ)的吸附容量仍达到初始吸附容量的93.7%。Langmuir和Freundlich方程均能用于描述香蕉皮粉末对Cr(Ⅵ)的吸附过程,表明存在单分子层和多分子层吸附,且为有利吸附。在298、308和318 K条件下,香蕉皮粉末对Cr(Ⅵ)的最大吸附量分别为149.25、161.29和169.49 mg·g^(-1)。准二级动力学模型更适用于拟合香蕉皮粉末对Cr(Ⅵ)的吸附过程,表明化学吸附占主导,发生电子转移。热力学参数表明,香蕉皮粉末对Cr(Ⅵ)的吸附是自发吸热熵增的反应。SEM结果显示,香蕉皮粉末呈片状结构,直径几十到数百微米,表面有褶皱和孔隙,提供了多个活性位点。SEM、FTIR和XPS分析结果表明,香蕉皮粉末对Cr(Ⅵ)的吸附机理包括静电吸引、氧化还原、表面螯合和离子交换。

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous solutions.Adsorption tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were investigated.The results showed that all composites were more efficient in lead removal compared to the fruit peels alone.The highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene glycol.This composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models,but the Langmuir model was more fitted than Freundlich.Besides,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(FTIR analysis),were studied.

Adsorption Isotherm Study of Activated Fruit Peels for Copper Removal

Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to process agricultural waste for heavy metal adsorption purpose.The objective of this study is to propose a new approach to treat banana peel using ZnCl_(2) prior to alkali and acid treatment and explore the potential of dragon fruit peels as the adsorbent for Cu^(2+)adsorption.Seven adsorption isotherm was adopted to identify the adsorption mechanism and four statistical parameters were calculated for model verification purpose.The experiment was conducted by dispersing ZnCl_(2) treated and untreated adsorbents into Cu^(2+) solution.Results showed that ZnCl_(2) treated adsorbents performed better in terms of Cu^(2+) removal compared with untreated adsorbents due to higher surface area for Cu^(2+) adsorption.The treated banana peel(Act.-B)performed approximately 30%better than the treated dragon fruit peel(Act.-D)due to the presence of hydroxyl and carboxyl groups.The equilibrium adsorptive capacity of Act.-B was 1872.8 mg Cu^(2+)/g and the experimental data fitted Freundlich isotherm well with R^(2)=0.9978,0.0161 of residual sum of error(SSE),0.0068 of χ^(2),and 0.0567 of root mean square error(RMSE)values.This suggests non⁃linear adsorption and multilayer adsorption on heterogenous surfaces.Thus,it is recommended to further improve the surface properties of Act.-B by steam pyrolysis and surface modification.

Formulation and evaluation of semisolid jelly produced by Musa acuminata Colla(AAA Group) peels

Objective:To study the jelly formulation produced by Musa acuminata Colla(AAA Group) peels and evaluate its antioxidant properties which are related to the product quality.Methods:The formulations of peel jelly were established under two-level full factorial designs within two blocks and one center point.Regarding response optimizer,the amount of sugar and citric acid was obtained;hence,the peel jellies were produced.The evaluation of antioxidant properties was conducted by using total phenolic content(TPC)assay and 1,1 diphenyl-2-picrylhydrazyl(DPPH) free radical assay.Results:The TPC of peel powder varied from 91.8 to 602.26 mg gallic acid equivalents/100 g dry weight,and 5%-7% peel jellies had phenolic content ranging from 29.38 to 48.31 mg gallic acid equivalents/100 g dry weight.The results of DPPH test indicated that at 10 mg/mL,the peel powder showed 89% DPPH inhibition,while 7% peel jelly prominently exhibited 84% DPPH inhibition.The correlation between DPPH IC50 value and TPC of peel powder as well as peel jelly was quite reasonably high with correlation coefficient ranging from 0.843 7 to 0.995.Conclusions:TPC can be used as an indicator in assessing the antioxidant activity of fruits and vegetables.The present investigation reveals that TPC is mainly responsible for DPPH free radical scavenging capacity.