Biomass Valorization of Walnut Shell for Liquefaction Efficiency

Globally, lignocellulosic biomass has great potential for industrial production of materials and products, but this resource must be used in an environmentally friendly, socially acceptable and sustainable manner. Wood and agricultural residues such as walnut shells as lignocellulosic biomass are one of the most affordable and important renewable resources in the world, which can partially replace fossil resources. The overall objective of the research is to provide background information that supports new applications of walnut shells in a biorefinery context and to increase the economic value of these non-wood forest products. This paper presents the properties characterization of liquefied biomass according to their chemical composition. All results were compared to liquefied wood. In this study, the liquefaction properties of five different walnut shell particle sizes were determined using glycerol as the liquefaction reagent under defined reaction conditions. The liquefied biomass was characterized for properties such as percentage residue, degree of liquefaction, and hydroxyl OH numbers. The chemical composition of the same biomass was investigated for its influence on the liquefaction properties. Accordingly, the main objective of this study was to determine the liquefaction properties of different particle sizes as a function of their chemical composition, also in comparison with the chemical composition of wood. The study revealed that walnut shell biomass can be effectively liquefied into glycerol using H2SO4 as the catalyst, with liquefaction efficiency ranging from 89.21 to 90.98%.

EFFECT OF CHARCOAL QUALITY ON TOXICITY OF HOOKAH TOBACCO

Анализ современного российского рынка табачной продукции свидетельствует о росте популярности смесей для кальяна. Особенностью данного продукта является специфика его потребления: нагрев с использованием натурального древесного или кокосового угля. Угарный газ – монооксид углерода в дыме кальяна появляется вследствие сгорания угля. Исследованы качественные характеристики угля для кальяна – влажность, продолжительность розжига и горения, динамика изменения температуры чаши и калауда в процессе работы кальянной системы – и его влияние на органолептические свойства кальянного дыма и содержание монооксида углерода в нем. В качестве объекта исследования были образцы угля для кальяна на основе скорлупы грецкого ореха (Украина), на основе скорлупы кокосового ореха (Индонезия), а также быстровозгорающийся древесный уголь, пропитанный селитрой (Польша). Установлено, что содержание монооксида углерода в аэрозоле при использовании угля из скорлупы грецкого ореха на 20% ниже, чем при использовании угля из скорлупы кокосового ореха, и в 10 раз ниже, чем при нагревании быстровозгорающимся древесным углем, пропитанным селитрой. Угли из скорлупы грецкого ореха и скорлупы кокоса имеют большую, чем быстровозгорающийся древесный уголь, продолжительность розжига, однако они характеризуются большей продолжительностью горения, меньше влияют на органолептическое восприятие курильщика и подходят для использования в любых кальянных системах (с калаудом и без него). Analysis of modern Russian market of tobacco products indicates that popularity of hookah tobacco is increasing. The main distinctive feature of this product is peculiarity of its consuming. It is heated by natural charcoal or coconut charcoal. Carbon monoxide in hookah aerosol appears due to burning process of utilized charcoal. Qualitative characteristics of charcoal – humidity, time of starting charcoal burning and time of burning, dynamics of temperature change of the bowl and kalaud during the hookah system are investigated. The effect of hookah charcoal on the organoleptic properties of hookah smoke and the carbon monoxide content in it has been determined. Samples hookah charcoal made of walnut shells (Ukraine), charcoal made of coconut shells (Indonesia), quick lighted charcoal made of wood charcoal and impregnated with niter (Poland) were used as the object of the study. It was found that the carbon monoxide content in the aerosol when using walnut shells charcoal is 20% lower than when using coconut shells charcoal, and 10 times lower than when using quick lighted charcoal. Despite the fact that charcoals from walnut shell and from coconut shell have a much longer time of starting burning than quick lighted charcoal, they are characterized by a longer burning, less affect the organoleptic perception of the smoker and are suitable for use in any hookah systems (with calaud and without it).

Study of the Potential Uses of Hydrochar from Grape Pomace and Walnut Shells Generated from Hydrothermal Carbonization as an Alternative for the Revalorization of Agri-Waste in Chile

A myriad of resources and efforts have been devoted to assessing the possibilities of using locally sourced biomass to produce energy, reduce CO2 emissions, and, in turn, lower dependance on petroleum. Grape pomace (GP) and walnut shells (WS) are organic waste generated in Chile. Within the last decade, the potential benefits and application of biomass have received significant attention, both in terms of producing functionalized carbon materials, and the various potential applications in the field of energy storage and environmental protection. The proposed research motivation is on the development of carbonous materials through thermal decomposition processes. Few researchers have addressed the idea of developing a multipurpose carbonaceous matrix from hydrochar, and there remains a need for an efficient method to obtain hydrochar specially from grape pomace. Hence, the general objective of this research is to study the potential of grape pomace and walnut shells treated with hydrothermal carbonization (HTC) as an alternative low-cost and efficient carbonous matrix. Proximate and elemental analysis was determined to distinguish the nature of the feedstock along with the hydrochar produced. Yield and reaction severity were also studied to study the impacts of temperature and residence time for both feedstocks. Successful results from the proposed work have broad applications for increasing the sustainability biomass applications, contributing to a positive economic impact.

The in situ remediation of aquaculture water and sediment by commercial probiotics immobilized on different carriers

In the present study, we investigated the effect of probiotics immobilized by oyster shells (Os), vesuvianite (Ve) and walnut shells (Ws) on the remediation of aquaculture water and sediment by analyzing the variation of ammonia-nitrogen (NH4–N), nitrate-nitrogen (NO3–N), nitrite-nitrogen (NO2–N), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (CODCr), as well as the microbiota of the water and sediment. The positive or negative effects of the treatment groups on the water quality parameters were both observed. Compared with their effects on water quality parameters, the treatment groups had better effects on sediment parameters. Group Ve had the best remediation effect of NH4–N and NO3–N in the sediment (decreased by 5.22 and 1.66 times, respectively). Group Os showed a lower relative concentration of TN and CODCr (decreased by 3.77 and 0.95 times, respectively). The high-throughput sequencing results revealed that the immobilized probiotics increased the relative abundances of functional bacteria in the treatment groups at the phylum and genus level. The above results showed that probiotics immobilized by oyster shells, vesuvianite and walnut shells positively affected the aquaculture environment's remediation, especially the sediment.

Walnut Shells as a Potential Fuel for Iron Ore Sintering

Iron ore sintering is a predominant process for fine iron ore and its concentrate to be applied in the blast furnace process. However, sintering produces a negative impact on the environment. One of the effective ways to reduce greenhouse gas emissions from iron ore sintering is to use CO2-neutral biomaterials for the fuel needs of this technology. Walnut shells (WNS) are a promising raw material for such fuel substitute. Herein, the effect of the raw and the pyrolyzed WNS with a constant fineness of 3-0 mm on the sintering process and the sinter properties were studied. The proportion of WNS in the fuel composition was set to 25 wt.%. It has been established that the use of WNS pyrolyzed up to 873 K is optimal. Additionally, the difference in the reactivity of WNS and coke breeze has provoked the studies on the influence of the pyrolyzed WNS size on the sintering process. WNS size was set to 1-0, 3-0, 5-0, and 7-0 mm. It has been found that the most optimal both for the iron ore sintering process and the sinter quality is the use of WNS with a particle size of 3-0 mm, subjected to preliminary pyrolysis up to 873 K.

Preparation and Characterization of Novel Magnesium Composite/Walnut Shells-Derived Biochar for As and P Sorption from Aqueous Solutions

Elevated or unnatural levels of arsenic (As) and phosphorus (P) concentrations in soils and waterbodies from anthropogenic sources can present significant hazards for both natural ecosystems and human food production. Effective, environmentally friendly, and inexpensive materials, such as biochar, are needed to reduce mobility and bioavailability of As and P. While biochar features several physicochemical properties that make it an ideal contaminant sorbent, certain modifications such as mineral-impregnation can improve sorption efficiencies for targeted compounds. Here, we conducted sorption experiments to investigate and quantify the potential utility of magnesium (Mg) for improving biochar sorption efficiency of P and As. We synthesized a Mg-modified walnut shells-derived biochar and characterized its ability to remove As and P from aqueous solutions, thereby mitigating losses of valuable P when needed while, at the same time, immobilizing hazardous As in ecosystems. SEM-EDX, FTIR and elemental analysis showed morphological and functional changes of biochar and the formation of new Mg-based composites (MgO, MgOHCl) responsible for improved sorption potential capacity by 10 times for As and 20 times for P. Sorption efficiency was attributed to improved AEC, higher SSA, chemical forms of sorbates and new sorption site formations. Synthetized Mg-composite/walnut shell-derived biochar also removed >90% of P from real samples of wastewater, indicating its potential suitability for contaminated waterbody remediation.