Yields Of By-products Research Articles

Effect of citric acid-ethylene glycol binders on the washcoat adhesion and activity of monolithic catalysts for the catalytic oxidation of dichloromethane

Supported Pt-Co/HZSM-5 catalyst was considered to have excellent activity and stability in the catalytic combustion of chlorinated VOCs, which face challenges in scale-up application. Herein, we used an organic binder (citric acid-ethylene glycol, denoted as CA-EG) to coat the catalyst slurry on honeycomb cordierite. Citric acid can help to synthesize a stable slurry and preserve the activity of the original catalyst powder compared to traditional binders (Al or Si gel). The structure of the reticular long-chain organics in CA-EG makes it highly adhesive and the CA-EG coating has excellent resistance to mechanical stability. Catalyst characterization shows that the catalysts using CA-EG as the binder had enhanced redox properties, richer surface adsorbed oxygen and a more complete pore structure. This resulted in catalysts with lower T90 and lower by-product yields. The monolithic Pt-Co/HZSM-5 catalyst exhibited excellent activity in the oxidation of dichloromethane (T50 = 246.9 °C and T90 = 334.1 °C), and showed stability for at least 48 h (at 90 % conversion with no noticeable drop). Moreover, the water resistance of the monolithic catalyst was also excellent. This study proved that the CA-EG binder is very suitable for the coating process of zeolite-based catalysts.

Influence of a Precursor Catalyst on the Composition of Products in Catalytic Cracking of Heavy Oil

Heavy oils are characterized by a high content of resins and asphaltenes, which complicates refining and leads to an increase in the cost of refinery products. These components can be strongly adsorbed on the acid sites of a supported catalyst, leading to its deactivation. Currently, various salts of group 8 metals are being considered for such processes to act as catalysts during oil cracking. At the same time, the nature of the precursor often has a significant impact on the process of refining heavy oil. In this work, catalytic cracking of heavy oil from the Ashalchinskoye field using different precursors (nanodispersed catalysts formed in situ based on NiO) has been studied. The cracking was carried out at 450 °C with a catalyst content from 0.1 to 0.5 wt.%. The catalytic cracking products were analyzed via SARA, GC, XRD and SEM. Nickel acetate and nitrate promote similar yields of by-products, while formate promotes higher yields of gaseous products. Formate and nickel acetate were shown to produce 1.8 and 2.8 wt.% more light fractions than nickel nitrate. When heavy oil is cracked in the presence of Ni(NO3)2∙6H2O, the maximum decrease in sulfur content (2.12 wt.%) is observed compared to other precursors. It has been found that the composition and morphology of the resulting nickel sulfides and compaction products are influenced by the nature of the catalyst precursor. XRD and SEM analyses of coke-containing catalysts indicate the formation of Ni9S8 and Ni0.96S phases during cracking when nickel nitrate is used and the formation of NiS and Ni9S8 when nickel acetate and formate are used.

Dealkylation of alkylphenols in phenol oil on acid zeolites

The majority of the phenolic compounds in coal tar are alkyl-substituted phenols. To overcome the difficulty of separation, zeolites catalyzed dealkylation of alkylphenols was studied in a slurry-bed reactor. ZSM-5 displayed higher catalytic performance than other zeolites within a group of acidic zeolites with various topologies (including SAPO-34, ZSM-23, MCM-22, USY, and Mordenite). The yield of phenol gradually increased together with the zeolite acidity, but the types and yields of byproducts also increased in step with it. The pore size of the zeolites was a significant influence at similar acidity. The micropore of ZSM-5 inhibited some bimolecular processes, decreasing disproportionation/transalkylation as a result of transition state shape selection. In this study, the reaction paths of alkylphenols were investigated, based on the composition of products catalyzed by different zeolites, the distribution of products under different conditions, and the reaction process of various alkylphenols. Reaction process of alkylphenols included dealkylation, isomerization, disproportionation, transalkylation, and C-C cracking. Dealkylation took the place of isomerization as the primary reaction when the reaction temperature exceeded 350 °C. Disproportionation, transalkylation, and C-C cracking were exacerbated by excessive temperature. In addition, excessive reaction time and pressure can exacerbate side reactions, alkylphenols yields and coke deposition.

Winter wheat crop production and its quality when using complex fertilizers

The purpose of the current study was to estimate the effect of mineral and complex fertilizers with macro- and microelements, methods, and methods of their application upon productivity and individual quality elements of crop products when cultivating winter wheat in the conditions of the North-West of the Russian Federation. The study was carried out on the experimental plots of the FSBSI FRC LK OP Pskov Research Institute of Agriculture in 2020–2021. The objects of the study were the winter wheat variety ‘Skipetr’, mineral and complex fertilizers. The main application of mineral fertilizers (N40P50K70) provided favorable conditions for plant nutrition from the beginning of a vegetation period. The use of complex fertilizers for crops helped eliminate the deficiency in nutrients in the following phases of development. The trials have established a positive effect of mineral and liquid complex fertilizers on winter wheat productivity improvement (from 0,32 to 0,96 t/ha according to the trial variants); on the nitrogen content in grain (by 9–13 %) with a stable level of phosphorus and potassium; on crude protein yield per unit area (from 1.5 to 44.8 kg/ha) with the yields of main and by-products; on the formation of more filled grain (by 0.5–2.6 g) with an increase in the mass fraction of raw gluten. The use of complex fertilizers ‘Kodafol’ and ‘Strada N’ during the vegetation period made it possible to obtain the greatest increase in a number of indicators. An estimation of the agronomic efficiency of the studied agricultural practices has shown that the greatest return on 1 kg of NPK in terms of productivity increase was achieved in the trial variants treated with ‘Kodafol’ (against the background of mineral nutrition N40P50K70) and ‘Strada N’ (against the background of N40P50K70+N20) with 4.7–6.7 and 4.8–6.8 kg of grain, respectively.

Non-carcass components of confined lambs in feedlot using red propolis extract

The objective of this work was to evaluate the non-carcass components of crossbred Santa Inês lambs finished in feedlot with the inclusion of different levels of red propolis extract (RPE). Thirty-five crossbred lambs were used with an average weight of 17.08 ± 2.36 kg and mean age of five months, distributed in a completely randomized design with five treatments and seven replications. The treatments evaluated were: 0; 7; 14 and 21 mL of extract/animal/day Before slaughter, each animal was individually weighed to obtain the body weight at slaughter (BWS). The weights and yields of non-carcass components were evaluated, weights and yields of regional dishes (Buchada and Panelada). The addition of different levels of red propolis extract (RPE) did not influence (p > 0.05) the weights and yields of non-carcass components, by-products and adipose deposits, to the weight and yield of regional dishes. The use of red propolis extract in diets up to the level studied (28 mL day-1) did not change the characteristics evaluated.

Understanding photochemical pathways of laser-induced metal ion reduction through byproduct analysis.

Laser-induced reduction of metal ions is attracting increasing attention as a sustainable route to ligand-free metal nanoparticles. In this work, we investigate the photochemical reactions involved in reduction of Ag+ and [AuCl4]- upon interaction with lasers with nanosecond and femtosecond pulse duration, using strong-field ionization mass spectrometry and spectroscopic assays to identify stable molecular byproducts. Whereas Ag+ in aqueous isopropyl alcohol (IPA) is reduced through plasma-mediated mechanisms upon femtosecond laser excitation, low-fluence nanosecond laser excitation induces electron transfer from IPA to Ag+. Both nanosecond and femtosecond laser excitation of aqueous [AuCl4]- produce reactive chlorine species by Au-Cl bond homolysis. Formation of numerous volatile products by IPA decomposition during both femtosecond and nanosecond laser excitation of [AuCl4]- is attributed to enhanced optical breakdown by the Au nanoparticle products of [AuCl4]- reduction. These mechanistic insights can inform the design of laser synthesis procedures to improve control over metal nanoparticle properties and enhance byproduct yields.

Pilot-scale evaluation of sulfite-activated ferrate for water reuse applications

Ferrate is a promising, “green” (i.e., iron-based) pre-oxidation technology in water treatment, but there has been limited research on its potential benefits in a water reuse (wastewater recycling) paradigm. Recent studies have shown ferrate treatment processes can be improved by activation, the addition of reductants (i.e., sulfite) to the reaction. Prior bench scale experimentation suggests sulfite-activated ferrate may be a feasible option for water reuse applications; however, extent questions need to be addressed. This study evaluated the viability of sulfite-activated ferrate in water reuse treatment through continuous-flow experiments using synthetic and field-collected secondary wastewater effluents. The effluents were processed through the piloting system which included various physicochemical processes such as ferrate pre-oxidation, coagulation, clarification, and dual-media filtration. In each trial, the system was run continuously for eight hours with data collected via grab samples and online instrumentation with real-time resolution. Results demonstrate that reuse systems using activated ferrate pre-oxidation can produce effluents with water quality meeting most regulatory requirements without major impacts on downstream physicochemical processes. When compared to traditional ferrate pre-oxidation, activation showed several improvements such as lower byproduct yields. Operationally, activated ferrate does increase the development of headloss across the dual-media filter. In general, sulfite-activated ferrate is viable in a water reuse setting, resulting in several improved water quality outcomes. Results from this work create a pathway for adaptation at scale.

Organic chloramines attenuation and disinfection by-product formation during UV, chlorination and UV/chlorine processes.

Organic chloramines (OCs) have become one of the research focuses in the field of drinking water treatment due to its limited oxidation and sterilization ability as well as potential cytotoxicity and genetic toxicity to the public. Among widespread OCs, produced by chlorinating cytosine are a typical one exists during chlorine disinfection. OCs degradation during UV, chlorination and UV/chlorine processes were systematically investigated. UV irradiation at 254nm could effectively degrade OCs by 96.6% after 60min, mainly because N-Cl bond had significant UV absorption at 250-280nm leading to the generation of Cl• and HO•. Direct chlorination had poor removal of OCs with the OCs concentration increased first and then decreased as time went by. On the other hand, the removal of OCs during UV/chlorination was much higher than that during chlorination, but was worse than that during UV alone. pH had a minor effect on OCs decomposition via UV irradiation, whereas the effect was pronounced in the chlorination and UV chlorine processes. UV wavelength can affect the degradation of OCs with efficiency decreased in the order of UV 254>UV 265>UV 275. The total yields of disinfection by-products (DBPs) during the degradation of OCs followed UV/chlorine>UV>chlorination. CH and DCAA were the two dominant types of DBPs among detected 7 DBPs. DBPs yield followed the order of UV254>UV265>UV275 at pH 6.0 and 7.0. After UV 265 irradiation, DBPs yield slightly decreased by 2.4%, 3.0% and 6.6% with the pH increased from 6.0 to 9.0. The results can provide theoretical basis for effective control of OCs in drinking water.

Synthesis and characterization of a computationally predicted redox and radiation stable deep eutectic solvent

• DFT calculations towards finding suitable HBD and HBA for the formation of redox and radiation stable DES. • Phase diagram to depict the molar ratio of the constituents in the new DES. • Stabilization energy calculation of the predicted new DES. • Experimental synthesis and characterization of the DES predicted from computational calculations. • Radiation stability study and by-product analysis of the as synthesized DES under gamma irradiation. A redox and radiation stable DES has been predicted based on the fundamental electronic properties such as energy gap, ionization potential and electron affinity computed applying suitable density functionals in combination with 6-311++G(d,p) set of atomic basis functions. A selected series of optimized hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs) has been screened using density functional theory (DFT). The long range corrected density functionals; ωB97XD and LC-BLYP are found to be cost effective and appropriate towards orbital energy gap calculations of such systems. Choline acetate and malonic acid appeared to be the most appropriate combination among those studied for formation of a chemical and radiation stable DES. Theoretically constructed phase diagram using Gibbs free energy minimization technique is applied to suggest the eutectic point and eutectic composition of the recommended DES. Stabilization energy calculations following electronic structure support the phase diagram data denoting formation of a stable eutectic with 1:2 stoichiometry. Density, viscosity, differential scanning calorimetry (DSC) and Fourier transform infra-red (FTIR) experiments have been carried out with this synthesized DES. Measured glass transition temperature (−75 °C) is observed to be lower than the theoretical eutectic point (−40 °C) indicating strong interspecies interaction within the medium. Experimental FTIR analysis gives an idea of the type and number of H-bonds present within the DES whereas computationally optimized 1:2 geometry identifies the specific H-bonds along with their distances. Irradiation of this new DES has been conducted at a constant dose of 100 kGy to observe the extent of degradation. UV–Vis and FTIR analysis does not denote generation of any new species within the liquid phase upon irradiation, however the yields of the gaseous by-products have been quantified by Gas Chromatography (GC).

Carcass characteristics and prediction of individual cuts and boneless yield of Bos indicus and Bos indicus × Bos taurus bulls differing in age

No study has reported the carcass characteristics or saleable meat yield prediction models for humped and humpless cattle beef bulls in South Asia. In this study, carcass characteristics and predicted individual meat cuts and boneless yields of Bos indicus and Bos indicus × Bos taurus bulls differing in age were investigated. A total of 96 humped (n = 48, Bos indicus) and humpless (n = 48, Bos indicus × Bos taurus) bulls aged 18–24 months and 25–36 months, were used. Carcass characteristics, meat cuts, and by-product yields of humped and humpless beef bulls were compared. The authors also developed prediction models to estimate the boneless and individual meat cut yields of the bulls through morphometry and hot carcass weight (HCW) by performing regression analysis. Carcass conformation and fatness classes were determined using the “EUROP” grading scheme, whereas; meat color, fat color, marbling score, backfat thickness, and ribeye area were assessed from ribeye steak using AUS-MEAT chiller assessment standards. Humpless and 25–36 months of age bulls exhibited relatively better grading characteristics (carcass conformation, ribeye area, and marbling score) and higher weights (live, carcass, meat cuts, and by-products) than humped and 18–24 months of age bulls, respectively. Linear body measurements explained 69.6% vs. 66% of the variance in forequarter yield, 78.1% vs. 59.7% of that in hindquarter yield, and 72% vs. 64.8% of that in total boneless yield of humped and humpless bulls, respectively. Furthermore, the HCW explained 92.9% vs. 92.8% of the variance in forequarter yield, 94.4% vs. 95.9% of that in hindquarter yield, and 96.4% to 97% of that in total boneless yield of humped and humpless bulls, respectively. Among the different meat cuts, the HCW explained the highest variances in blades and silversides (90% and 93.3%, respectively), whereas the lowest variances were observed in cube rolls and foreleg shins (37.4% and 34.8%) in humped and humpless bulls, respectively. The results of the present study suggest that humpless and 25–36 months of age category bulls could be used to obtain superior quality carcasses with optimum meat production to meet the demands of meat importers. Moreover, linear body measurements and HCW could play an essential role in the cost-effective prediction and value-based marketing of individual meat cuts and the total boneless yield of humped and humpless bulls. However, further studies with large datasets are needed to validate the prediction model equations developed in this study.

Simultaneous improvement of lincomycin A production and reduction of lincomycin B levels in Streptomyces lincolnensis using a combined medium optimization approach

PurposeThe current study aimed to optimize the culture and production parameters of industrial production of lincomycin A by Streptomyces lincolnensis using a statistical approach that could also reduce unwanted by-products.MethodsThe Plackett-Burman design, steepest ascent method, and response surface design were used to evaluate different factors that affect lincomycin A production.ResultsUsing an optimized S. lincolnensis fermentation medium, lincomycin A production was increased up to 4600 mg/L in shaking flasks, which indicated a 28.3% improvement over previous production in an un-optimized medium (3585 mg/L). Additionally, the concentration of lincomycin B by-product was reduced to 0.8%, which was 82.2% lower than that in the un-optimized medium. Further, quantitative real-time PCR analysis revealed the optimized medium improved lincomycin A production by stimulating key genes in the lincomycin A biosynthesis pathway, as well as an osmotic stress gene.ConclusionsBased on the results, the sequential optimization strategy in this study provides powerful means for the enhancement of lincomycin A with less by-product. We found that osmotic stress reduced the concentration of lincomycin B, which could also help reduce fermentation by-product yields in other actinobacteria.

RSM-Modeling and Optimization of High Titer Functional Xylo-oligosaccharides Production by Edible Gluconic Acid Catalysis.

Xylo-oligosaccharides have great value in food, feed fields. Previous studies have shown that organic acids catalyze the hydrolysis of xylan-rich sources for the production of xylo-oligosaccharides. In this study, gluconic acid of aldonic acid generated xylo-oligosaccharides via hydrolysis of xylan from corncob. In order to maximize efficiency of xylo-oligosaccharides production, the optimum conditions was ascertained by Box-Behnken design-based response surface methodology. The developed process resulted in a maximum xylo-oligosaccharides yield of 57.73% using 4.6% gluconic acid at 167°C for 28min, which was similar to the predicted value and fitted models of xylo-oligosaccharides production. The results showed that the reaction temperature was crucial to xylo-oligosaccharides production, and by-product yields (xylose and furfural) could be effectively controlled by both reaction temperature and time. In addition, 44.87g/L XOS was achieved by decreasing the solid-liquid ratio. Overall, the described process may be a preferred option for future high concentration xylo-oligosaccharides production.

Mono- and Bimetallic Silver-Containing Nitrogen-Doped Carbon Composites and Their Electrocatalytic Activity

The N-doped metal-carbon composites based on the carbonized melamine-formaldehyde polymer (MFP) with silver, silver-copper, and silver-cobalt particles were synthesized. Mono- and bimetallic silver-containing composites were prepared by the reduction of metal nitrates with hydrazine hydrate in an aqueous ethanol medium in the presence of carbon black particles obtained by the heat treatment of MF-polymer at 500 °C. The structural-phase changes before and after the use of metal-carbon composites as electrocatalysts in the electrohydrogenation of p-nitroaniline (p-NA) were studied by X-ray diffraction analysis. The morpho-logical features of the created MFBC + Ag, MFBC + (Ag+Cu) and MFBC + (Ag+Co) composites were stud-ied by electron microscopy. It was established that the synthesized composites mainly contain crystalline phases of the corresponding reduced metals or their alloys. The monometallic MFBC(1) + Ag(1) composite contains reduced silver crystallites of various shapes and localization on porous MF carbon black particles. Higher electrocatalytic activity of the synthesized Ag-containing composites in the p-NA electrohydro-genation was shown in comparison not only with the electrochemical reduction of p-NA but also with MFBC + (Ag+Cu) composites with electrocatalytic hydrogenation of p-NA on Ag + Cu particles (without MFBC). It was found that the use of the studied MFBC-composites increases the selectivity of the formation of the main hydrogenation product (p-phenylenediamine) and decreases the yields of by-products.

Lysine effect on the characterization of fillet, by-products, residues, and morphometry of tambaqui Colossoma macropomum (Cuvier, 1818)

This study aimed to evaluate the yields of by-products and residues and the morphometry of juvenile tambaqui Colossoma macropomum undernutrition with different levels of lysine. Diets were elaborated containing 6.60, 9.72, 12.84, 15.96, 19.08, and 22.20 g kg -1 of total lysine, and these were fed to fish distributed in 18 tanks (310 L each one) for 90 days. Morphometric analysis, measurements of whole fish, by-products, and residues were taken and compared to each other. All variables were validated using ANOVA, Tukey's test, and quadratic regression analysis ( P < 0.05). No differences were found for the morphometric variables ( P > 0.05). The ratio between morphometric data for the standard and total length showed significance at levels of 9.72 and 15.96 g kg -1 ( P = 0.03). The gutted fish and fillets, the protein and lipid contents of the fillets, and the weights and lengths of the intestines did not change ( P > 0.05). Moisture was modified with lysine at levels of 22.20 g kg -1 ( P = 0.00), and minerals, between 6.60 and 22.20 g kg -1 ( P = 0.01). The increase in lysine levels in the diet led to an increase in fin weight ( P = 0.00). It was concluded that the addition of lysine in the diet did not directly influence the morphometry and yields of the fish in the juvenile phase, but it did affect the fin waste and the skin by-product.

Catalytic oxidation of dichloromethane over Pt-Co/HZSM-5 catalyst: Synergistic effect of single-atom Pt, Co3O4, and HZSM-5

The catalytic degradation of chlorinated volatile organic compounds (CVOCs) at low temperatures is a great challenge. In this work, Pt-Co/HZSM-5 ternary catalysts were synthesized and used for the catalytic oxidation of dichloromethane (DCM). By adding only trace amounts of Pt (0.01 wt. %), Pt-Co/HZSM-5 ternary catalyst exhibits better CO2 yield and lower by-product yield than Co/HZSM-5 catalyst. Besides, it maintained stable activity for at least 45 h without substantial changes. The addition of water vapor to the DCM degradation process on Pt-Co/HZSM-5 ternary catalysts was shown to promote DCM conversion, CO2 yield, and HCl yield. Catalyst characterization shows that Co (in the form of Co3O4) could effectively anchor Pt atoms, thus realizing the single-atom dispersion of Pt. In turn, the formed single-atom Pt increases the proportion of oxygen vacancies on the surface of Co3O4, thereby enhancing the redox properties of Co3O4. In the catalytic oxidation process, DCM first adsorbed and dechlorinated on the surface of HZSM-5 due to abundant acid sites and then completely dissociated under the interaction of Pt and Co. Thanks to the synergies of Pt, Co, and HZSM-5, Pt-Co/HZSM-5 exhibited appropriate redox ability, a suitable distribution of acid sites, and sufficient surface adsorbed oxygen, possibly explaining its lower by-product yields and the more efficient formation and desorption of HCl.

Variations of disinfection byproduct precursors through conventional drinking water treatment processes and a real-time monitoring method

In this investigation, raw water (RW), settled water (SW), and filtered water (FW) collected from a drinking water treatment plant were fractionated into 24 natural organic matter (NOM) fractions with varying molecular weights and hydrophobicity. The yields of disinfection byproducts (DBPs) obtained during the chlorination of the NOM fractions were explored. Results revealed that the 0–1 kDa, 5–10 kDa, and hydrophobic DBP precursors dominated RW. Hydrophobic fractions cannot be effectively removed, which contributed to the high DBP precursors remaining in the FW. The optional optical parameters, including UVA (UV340, UV360, and UV380), UVB (UV280, UV300, and UV310), and UVC (UV254, UV260, and UV272), were analyzed to determine the DBP yields during chlorination of different NOM fractions. Results revealed that UVC could be applied to indicate the regulated DBP yields of the humified precursors. Contrary to the generally accepted view, for biologically derived precursors, their regulated DBPs and dichloroacetonitrile correlated better with UVA (e.g. UV340). Moreover, PARAFAC analysis was applied to decompose an array of 24 EEM spectra. Good linear correlations were found between the PARAFAC components and most DBP yields. Furthermore, four fluorescence parameters were proposed via a modified fluorescence picking method, which can serve as excellent surrogates of PARAFAC components. These fluorescence parameters were found to be effective in indicating most DBP yields. Finally, the fluorescence intensity at excitation wavelength/emission wavelength = 310/416 nm was found to be a promising built-in parameter for the real-time monitoring of DBP precursors, regardless of the humification degree of the precursors.

Degradation of atrazine (ATZ) by ammonia/chlorine synergistic oxidation process

Chlorination is widely used for disinfection of water and wastewater. Ammonia/chlorine co-exposure can be easily achieved when ammonia is present in water. In this study, ammonia and chlorine showed synergistic effect on atrazine (ATZ) degradation. A degradation efficiency of 50.2% was obtained in 10 min with a Cl/N molar ratio of 1.6. By contrast, free chlorine and chloramines barely degraded ATZ. The synergistic effect involved formation of hydroxyl radicals (OH) and reactive chlorine species. The radical concentrations followed the order of ClO (4.8 × 10−13 M) > OH (4.1 × 10−13 M) > Cl (3.0 × 10−15 M). The dominant radical was OH (>80% contribution), followed by ClO (less than18% contribution), which had relatively lower reactivity with ATZ. The synergism was pH dependent, with OH largely suppressed by 98% when the pH was acidic or basic rather than neutral, resulting in a decrease in ATZ degradation. The transformation products detected indicated that ATZ degradation involved dealkylation and dechlorination–hydroxylation, and lower yields of oxidation byproducts were obtained by ammonia/chlorine synergistic oxidation process compared to direct chlorination.

A novel recyclable furoic acid-assisted pretreatment for sugarcane bagasse biorefinery in co-production of xylooligosaccharides and glucose

BackgroundPretreatment is the key step for utilizing lignocellulosic biomass, which can extract cellulose from lignin and disrupt its recalcitrant crystalline structure to allow much more effective enzymatic hydrolysis; and organic acids pretreatment with dual benefic for generating xylooligosaccharides and boosting enzymatic hydrolysis has been widely used in adding values to lignocellulose materials. In this work, furoic acid, a novel recyclable organic acid as catalyst, was employed to pretreat sugarcane bagasse to recover the xylooligosaccharides fraction from hemicellulose and boost the subsequent cellulose saccharification.ResultsThe FA-assisted hydrolysis of sugarcane bagasse using 3% furoic acid at 170 °C for 15 min resulted in the highest xylooligosaccharides yield of 45.6%; subsequently, 83.1 g/L of glucose was harvested by a fed-batch operation with a solid loading of 15%. Overall, a total of 120 g of xylooligosaccharides and 335 g glucose could be collected from 1000 g sugarcane bagasse starting from the furoic acid pretreatment. Furthermore, furoic acid can be easily recovered by cooling crystallization.ConclusionThis work put forward a novel furoic acid pretreatment method to convert sugarcane bagasse into xylooligosaccharides and glucose, which provides a strategy that the sugar and nutraceutical industries can be used to reduce the production cost. The developed process showed that the yields of xylooligosaccharides and byproducts were controllable by shortening the reaction time; meanwhile, the recyclability of furoic acid also can potentially reduce the pretreatment cost and potentially replace the traditional mineral acids pretreatment.

A New Model of Alcoholic Fermentation under a Byproduct Inhibitory Effect.

Despite the advantages of continuous fermentation whereby ethanol is selectively removed from the fermenting broth to reduce the end-product inhibition, this process can concentrate minor secondary products to the point where they become toxic to the yeast. This study aims to develop a new mathematical model do describe the inhibitory effect of byproducts on alcoholic fermentation including glycerol, lactic acid, acetic acid, and succinic acid, which were reported as major byproducts during batch alcoholic fermentation. The accumulation of these byproducts during the different stages of batch fermentation has been quantified. The yields of total byproducts, glycerol, acetic acid, and succinic acid per gram of glucose were 0.0442, 0.023, 0.0155, and 0.0054, respectively. It was found that the concentration of these byproducts linearly increases with the increase in glucose concentration in the range of 25–250 g/L. The results have also showed that byproduct concentration has a significant inhibitory effect on specific growth coefficient (μ) whereas no effect was observed on the half-velocity constant (Ks). A new mathematical model of alcoholic fermentation was developed considering the byproduct inhibitory effect, which showed a good performance and more accuracy compared to the classical Monod model.

Availability and estimation of crop by-product yields for small ruminant production in Cross River State, Nigeria

A study was carried out in some Local Government Areas of Cross River State of Nigeria to identify and ascertain the availability, level of production and the yields of crop by-products derived from commonly cultivated crops that can serve as feed for small ruminants. The results show that the various staple crops commonly grown in Cross River State produce the following crop by-products in a decreasing order of yields- cassava peels> yam peels> corn cobs> maize sheaths> plantain peels> maize offal> rice offal> cassava sievets> banana peels> fried garri sievets> groundnut haulms> sweet potato peels. The annual yield of crop by-products per Local Government Area is estimated as follows: cassava peels 89,226.40, yam peels 32,318.80, maize sheaths and offal 358,050.00, rice 0ffal 37,140.00, cowpea haulms 34,064.00, groundnut haulms 41,872.00, banana peels and rejects 18,420.00, plantain peels 7,598.40, cocoyam peels 11,944.00, sweet potato peels and rejects 8,024.00 tonnes per selected LGA.The total amount of crop by-products (638,657.60 tonnes) generated each year from the staple food crops will go a long way in solving the problem of feed scarcity for ruminants during dry season.