Effect Of Perlite Research Articles

Effect of perlite on the thermal conductivity, thermal degradation and mechanical properties of epoxy materials

In this study, the thermal conductivity, thermal degradation and mechanical properties of the perlite added epoxy materials were investigated. Perlite was added into the epoxy resin (EP) at the rate of 2%, 4%, 6%, 8% and 10% compared to the total mass. For the analysis of these epoxy materials, the thermal conductivity, density, hardness, X-ray diffraction (XRD), FTIR spectra, thermogravimetric analysis (TGA), tensile strength, flexural strength, limit oxygen index (LOI) and vertical burning tests were carried out. With the added perlite (PER10), a decrease of 24.03% occurred in the thermal conductivity coefficient compared to the pure EP material. A maximum decrease of 6.86% was detected in its density. It gained fire retardant feature as it increased from 6.15% to 28.71% in V-0 and carbon residue as inflammability class. Despite the decrease of tensile stress, tensile modulus increased. The maximum increase PER02 was 36.9%. It did not provide any improvement in terms of other mechanical properties.

Effects of perlite, grass charcoal and vermiculite on root growth of isatis (Isatis tinctoria L. Woad) and soil nutrient migration

Effects of perlite, vermiculite, and grass charcoal on root growth of Isatis and soil nutrients migration were studied, and the plant growth indicators and some soil properties of upper (0~5cm) and lower layer (5~15cm) were analyzed. The experiment treatments were loess (CK), loess : perlite = 3 : 1(A), loess : grass charcoal = 3 : 1(B), loess : vermiculite = 3 : 1(C), loess: perlite: grass charcoal = 6 : 1 : 1(A1), loess: perlite: vermiculite = 6 : 1 : 1(B1), loess: grass charcoal: vermiculite = 6 : 1 : 1(C1). The results showed that soil pH of vermiculite-containing treatments in the upper layer and grass charcoal treatment in the lower layer decreased significantly. Before planting, the available potassium and phosphorus of the upper layer were significantly higher than those of the lower layer, and soil organic matter (SOM) was slightly higher than that of the lower layer. After planting, the decrease of available potassium in the upper layer was less than that of the lower layer, and the decrease of available phosphorus and increase of SOM in the upper layer were slightly higher than that of the lower layer. In sum, it is preferred to choose B (loess : grass charcoal = 3 : 1) and A1 (loess: perlite: grass charcoal = 6 : 1 : 1) to improve the soil nutrient and utilization efficiency. Bangladesh J. Bot. 50(3): 947-954, 2021 (September) Special

Effect of acidic volcanic perlite rock on physio-mechanical properties and microstructure of natural pozzolan based geopolymers

The paper presents the combined effect of pozzolan, as an alkaline volcanic rock, and perlite, as an acidic volcanic rock, in the synthesis of geopolymers. The perlite proportion varied between 0% and 50% by weight. A mixture of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) was used as an alkaline activator. The effect of perlite on the physio-mechanical properties of the synthesized geopolymers was evaluated by the compressive strength (Rc), P-wave velocity (Vp), bulk density (D), and porosity (P). The microstructural aspects have been explored by X-ray Diffractometry (XRD), Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and Energy-Dispersive X-ray spectroscopy (EDS). The results highlight the possibility of obtaining an eco-efficient geopolymer, with compressive strength of up to 50 MPa at 28 days by partially replacing the pozzolan by 40% of the perlite, due to the formation of higher amorphous N-A-S-H type gel. However, the excessive content (more than 40%) of perlite favored the formation of zeolitic phases in the geopolymer matrix, resulting in a heterogeneous structure, which has a negative effect on the development of the compressive strength and microstructure of the pozzolan-based geopolymer. This study confirms the promise of using pozzolan-perlite-based geopolymers as sustainable building materials, which could significantly promote the development of geo-resources and environmental protection in the construction sector.

Are biosynthesized nanomaterials toxic for the environment? Effects of perlite and CuO/perlite nanoparticles on unicellular algae Haematococcus pluvialis.

The properties of nanomaterials such as perlite nanoparticles and their increased application have raised concerns about their probable toxic impacts on the aquatic ecosystems and algae. Here, a novel biochemical synthesis and immobilization of CuO is reported on perlite nanoparticles (CuO/Per-NPs) and its toxic effect on alga has been compared with nanoperlites. This biosynthesis of CuO/Per-NPs performed using phytochemicals of Haematococcus pluvialis, Sargassum angustifolium, and walnut leaves in the aqueous extract. The structural, morphological, and colloidal properties of the as-synthesized nanoparticles have been confirmed by various methods. According to the obtained results, the morphology of the synthesized CuO/Per-NPs was spherical with sizes ranging from about 13 to 24 nm. Besides, the effects of Per-NPs and CuO/Per-NPs on unicellular algae H. pluvialis were studied. The changes in the amount of chlorophyll a, chlorophyll b, and Carotenoids in the presence of different concentrations of Per-NPs (25, 50, 100 mg/L) were more than CuO/Per-NPs. Also, decreased growth rate and efficiency of photosystem II confirmed the toxic effects of Per-NPs. However, the toxicity of CuO/Per-NPs appears to be lower than that of Per-NPs, which can be due to the changes in the surface and cationic charge of modified nanoperlit. These changes lead to a decrease in the interaction of nanoparticles with H. pluvilalis and a reduction in ROS production. Finally, the results of GC-MS used to evaluate volatile compounds, indicated an increase in the number of phenolic compounds in comparison to the control samples in 25, 50, and 100 mg/L treatments of nano-perlite.

Impact of Perlite on the Properties and Stability of Water-Based Mud in Elevated-Temperature Applications.

Barite settling is one of the common drilling fluid issues encountered while drilling deep wells. In this study, the effect of perlite on the properties and stability of water-based drilling fluid was investigated. Perlite is an inexpensive additive used in different industrial applications such as bricks, concrete, thermal insulators, sludge absorbents, fillers, tiles, ruminants, and poultry. Perlite additive was also introduced to the oil industry in drilling applications as an effective fluid loss control agent to reduce the drilling fluid invasion into the formations. Perlite was added to the drilling fluid in various concentrations, ranging between 0 and 3.0 lb/bbl. The sag test was performed to assess the drilling fluid’s stability under dynamic and static conditions at a temperature of 120/250 °F. Then, the impact of perlite on the properties of drilling fluid was assessed by measuring the density and pH at room temperature. While the rheological, viscoelastic, and filtration properties were evaluated at 250 °F. This study showed that an increase in perlite concentration, from 0 to 3 lb/bbl, slightly reduced the pH of the drilling mud; however, all of the values were within the acceptable pH range (9–11). In contrast, this concentration of perlite had an immeasurable impact on drilling fluid density. Perlite enhanced the drilling fluid’s homogeneity and stability by reducing the dynamic and static sag factors, and 3.0 lb/bbl perlite was adequate to eliminate barite sag at a temperature up to 250 °F. Perlite was found to be effective in improving the rheological and viscoelastic properties. A significant enhancement of filtration properties was observed by the reduction in filtrate volume and filter cake thickness by 64 and 31%, respectively.

Effects of Perlite, Leca, and Scoria as Lightweight Aggregates on Properties of Fresh and Hard Self-Compacting Concretes

Effects of Perlite, Leca, and Scoria as Lightweight Aggregates on Properties of Fresh and Hard Self-Compacting Concretes

The use of perlite as flux in the production of porcelain stoneware tiles

In this study, the effect of perlite from NW Turkey on the physical properties of ceramic tile bodies was investigated. The phases present in the raw materials were measured by X-ray diffraction while chemical analysis of the raw materials were determined by X-ray flouresence. Colour, water absorption and firing shrinkage of the raw materials were investigated. The data obtained from this study showed that the addition of NW Turkey perlites improved sintering behaviour of ceramic tile bodies, Therefore, alternative tile compositions were formulated using perlite as a substitute for common alkali bearing raw materials. The sintering behaviour of the standard bodies and that of the perlite containing bodies were characterized using a double-beam optical non-contact dilatometer. Moreover, the effect of perlite on firing shrinkage (%), water absorption (%), apparent porosity (%), apparent density (g/cm3), bending strength and colour values (L, a, b) were studied and resultant microstructures were characterized by X-ray diffraction (XRD) and scanning electron microscope studies (SEM). It was clearly observed that perlite improves sinterability of the tile bodies but increases the firing shrinkage due to the presence of water in its structure. The low thermal expansion values of the sintered bodies containing perlite makes it a visible raw material for porcelain stoneware tiles.

Physical-mechanical properties of steel fibre-reinforced self-compacting concrete containing natural perlite addition

The aim of this work is to highlight the effect of the Algerian natural perlite used as fillers addition on the workability and physical-mechanical properties of metallic fibre self-compacting concrete (SCC). Effect of the perlite is compared to that of silica fume fillers to replace limestone fillers. One control concrete without fibres containing limestone fillers, two concretes with silica fume or perlite fillers and six SCCs were elaborated with limestone, perlite and silica fume fillers separately containing 1% vol. of steel long wavy or short hooked fibres. Several tests were conducted for evaluating the workability properties in the fresh state, the density, mechanical strengths and elastic modulus in the hardened state. The results show the beneficial effect of the use of perlite as fillers. Workability properties decrease slightly but an increase of mechanical strengths and elastic modulus is much more marked with the use of the steel hooked fibres.

Effect of Perlite on Fire Protection of Waterborne Coatings for Steel Structure

In this paper, perlite was used as a kind of modifier to prepare waterborne fire resistive coatings for steel structure. The influence of perlite on the properties of the fire resistive coatings was investigated with the help of thermogravimetric analysis (TGA), micro-scale combustion calorimetry (MCC) and fire protection test. The TGA results showed that the char residue weight of the coatings was increased when perlite was loaded and the anti-oxidation performance was enhanced as well and MCC data indicated the addition of perlite reduced the peak heat release rate and total heat release. After the fire protection test, the results confirmed that the fire resistant time of the coating coated with 5 wt% perlite increased up to 114.4 min when the temperature of the sample boards’ backside reached 500?C.

Effect of Perlite on Reducing Water Stress for Three Genotypes of Tomatoes Solanum lycopersicum L. 1. Vegetative growth

Effect of Perlite on Reducing Water Stress for Three Genotypes of Tomatoes Solanum lycopersicum L. 1. Vegetative growth

Effects of perlite and caustic soda on microorganism activities of leachate in a sequence batch reactor

ABSTRACTThe purpose of this article is to evaluate the effect of adsorbents and alkali pre-treatment on microorganism activities of activated sludge (AS) for the treatment of landfill leachate (LFL). The chemical oxygen demand (COD) and BOD5/COD ratio of LFL used in this research were 10,500 and 0.68, respectively. In order to survey the role of porous absorbent, perlite was employed as an alternative with low porosity and was compared to powdered activated carbon (PAC), which has been most widely used in the treatment process. As a result, the COD removal efficiency increased from 32% to 47.7% when alkali LFL was loaded to the sequence batch reactors (SBRs) at the optimum conditions of the biological process. Also, at the same condition, both SBRs containing PAC and perlite showed COD removals of over 81% and 72%, respectively. The specific oxygen uptake rate (SOUR) showed that alkali pre-treatment reduces the toxicity effect of heavy metals on microorganism activities. The adsorption capacity (the uptake of COD) was analyzed by Langmuir and Freundlich isotherm models. Further, the kinetic study of COD adsorption during the treatment process demonstrated that the alkali pre-treatment of LFL proceeded faster and was intensified by the presence of adsorbents.

Temporal variation of total and DTPA-extractable heavy metal contents as influenced by sewage sludge and perlite in a calcareous soil

ABSTRACTContinuous application of sewage sludge (SS) as a source of organic matter, may increase available heavy metals (HMs) up to their critical levels. As a consequence their uptake by plants, risks of accumulation in food chain and groundwater pollution increases. To evaluate the effects of perlite and SS on total content and available fraction of iron (Fe), manganese (Mn), lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd) and zinc (Zn) over 45 and 90 days a completely randomized pot experiment was conducted. Treatments consisted of SS (0, 2 and 4%) and combined SS and perlite levels (1:1, 1.5:0.5 and 0.5:1.5% SS:perlite). Mean available Fe, Ni, Cd, Mn and Zn fractions decreased over time by 7–27%, whereas, total contents did not change. Available HMs in SS-treated soils increased by 0.5–25%; whereas, only total Zn, Cu and Pb concentrations increased with SS application (although concentrations fall in the range of critical levels). The lowest (1.6 fold) and highest (22.1 fold) increases obtained for available Cu and Zn, respectively. Perlite could mitigate the adverse effect of high rate application of SS on amplification of HMs extractability. Therefore, their concomitant applications can be suggested considering the perlite durability and its positive effects on soil physical properties.

Effect of Perlite on Thermal Conductivity of Self Compacting Concrete

Cement concrete pavement slabs used in highway construction are planer structures. Apart from regular factors considered in analysis of concrete pavements, temperature effects influence the slab size, joint spacing and temperature reinforcement design. The thermal performance of concrete pavement is governed by its thermal properties viz. coefficient of thermal expansion, specific heat and thermal conductivity. Studies have been undertaken to assess the thermal properties of normal concrete. The measurement of thermal conductivity for Self Compacting Concrete (SCC) has been proposed in this paper. SCC is a highly flowable and non-segregating concrete. SCC has the ability to flow through congested reinforcements efficiently irrespective of the structure geometry.An experimental program has been undertaken, to assess the thermal conductivity values for M-40 grade of SCC mixes with manufactured sand. Class C flyash has been used as a cement replacement material. Perlite has been used as fine sand replacement material. The thermal conductivity values were measured using Guarded Hot Plate method (ASTM C177) as recommended in ACI 122R. This paper is an attempt to present the experimental results obtained for thermal conductivity studies undertaken on M-40 grade of SCC with optimized flyash dosage and perlite dosage.

Water Loss and Survival of Stem Cuttings of Two Maple Cultivars Held in Subirrigated Medium at 24 to 33 °C

We determined transpiration rate, survival, and rooting of unmisted, softwood cuttings of `Autumn Flame' red maple (Acer rubrum L.) and `Indian Summer' Freeman maple (Acer ×freemanii E. Murray). Effects of perlite at 24, 30, and 33 °C were assessed to determine whether responses of cuttings would be consistent with cultivar differences in resistance to root-zone heat previously shown with whole plants. During 7 d, cutting fresh mass increased by ≈20% at all temperatures for `Autumn Flame' red maple, but fresh mass of `Indian Summer' Freeman maple decreased by 17% and 21% at 30 and 33 °C, respectively. The percentage of cuttings of `Indian Summer' that were alive decreased over time and with increasing temperature. Transpiration rate decreased during the first half of the treatment period and then increased to ≈1.1 and 0.3 mmol·m-2·s-1 for `Autumn Flame' and `Indian Summer', respectively. Mean rooting percentages over temperatures for `Autumn Flame' and `Indian Summer' were 69 % and 16%, respectively. Mean rooting percentages at 24, 30, and 33 °C over both cultivars were 74%, 29%, and 25%, respectively. Over temperatures, mean root count per cutting was 41 and seven, and mean root dry mass per cutting was 4.9 and 0.4 mg, for `Autumn Flame' and `Indian Summer', respectively. Use of subirrigation without mist to root stem cuttings was more successful for `Autumn Flame' than for `Indian Summer'. Temperature × cultivar interactions for cutting fresh mass and the percentage of cuttings remaining alive during treatment were consistent with previous evidence that whole plants of `Autumn Flame' are more heat resistant than plants of `Indian Summer'. Mass and survival of stem cuttings during propagation in heated rooting medium may serve as tools for screening for whole-plant heat resistance among maple genotypes.