Economic Feasibility and Industrial Prospects of Aerogels

Author: Amit Prajapati

Abstract:

With an ever-growing demand for better material to suffice the need of petrochemical, oil-refinery, building refurbishment, aerospace, construction, Energy & quantum electronic industry. Properties of Aerogel makes a great contender for a wide spectrum of applications. The base materials used to synthesize aerogel make it very robust for real-life implementation. Aerogel is being manufactured on a commercial scale, the most common of all is the silica aerogel which was the first aerogel that was commercially available with direct utilization in R&D and insulation. Carbon and metal-oxide aerogels are finding their use in the catalysis and nanotechnology industry and are expensive to synthesize. Aerogel’s most common utilization is insulation in the coldest region of the world with properties such as low thermal conductivity and low density. The market of aerogel will grow from the current $600 million to $1.04 billion by the year 2025. The growth rate of the aerogel market is expected to be at $390 million between 2021 and 2025.

Introduction:

Aerogels are applicable in many industrial operations their properties attribute to their wide array of applications. Aerogels are one of the most ultra-light, least dense and highly porous materials known to exist which are also super insulators and they find their utilization in the field of insulation. Aerogels can be made mechanically stable when base materials are selected according to the requirement of their allocation in the industry. Aerogels are sometimes 98% air by volume and super insulators which makes them highly compatible to replace traditional insulating materials which are not only bulky but also provide insulation level as one-third of that provide by blanket aerogels. The starting material of aerogel could be a waste product like used tires or organic matter. This not only helps in recycling old products but is cost-effective as starting material would be inexpensive and in the process of reusing it again would be environment friendly.

1. Silica Aerogel’s economic feasibility.

Silica Aerogels are most easily accessible because they were the first to be commercialized. The cost of production increases at each step of the synthesis. The primary step while making silica sol requires precursors like TMOS(Tetramethoxysilane) or TEOS(Tetraethoxysilane) which are hazardous and expensive. Inputs like alcohol could be recycled to bring down the cost. Further processes to dry the wet sol-gel involves Supercritical drying which requires an autoclave that is exorbitant in price value. The energy consumption includes processes like supercritical drying, proportionally heating the autoclave. Moreover, an easier approach to render the wet sol-gel dry has open ways for ambient pressure drying and freeze-drying and the use of easily available precursors to extract silica for synthesis. While silica aerogel has a high thermal resistance and low density, they are brittle and hydrophilic which is not sufficient for their direct use in rigorous tests and applications therefore, silica aerogels are made hydrophilic for economical usage. The cost distribution for the production of silica aerogels includes material, power consumption, labour, and facility capital. These vary in their dynamics as a material investment could be brought down using different precursors like bagasse ash for silica extraction and inexpensive solvents for sol-gel preparation.

2. NASA’s stardust mission

NASA stardust mission was solely based on finding comic dust and analysing them to search for signs of organic matter like amino acid or water. The mission was launched in 1999 and the expenditure on the mission was roughly $200 million. The expenditure on construction and development of the project cost $128 million. The only material that could be utilized for the mission was Silica aerogel with ultra-lightweight and high-density gradient for capturing fast-moving dust particles without affecting the physical nature of the material. Mass of the capturing medium matters greatly because a slight variation in mass on the higher side would increase the payload and hence would lead to an increase in post-production expenditure on fuel.

3. Aerogel as a super Insulator for industrial and real-life application

The most prominent use of aerogels is in the field of insulation, clothing, and cryogenic applications. Aerogel has been a promising thermal insulator in the area such as building insulation but due to its high cost of production few products are available in the market. For building insulation, the primary material used for aerogel preparation is organic matter which when transformed to aerogel shows robust mechanical strength as compared to those made from inorganic material such as silica or metal oxide. The market demands for more robust and lighter insulation material and polymer aerogels with reinforced carbon nanofibers fulfil the requirement, it’s experimentally determined that when more carbon nanofibers are used in the making of polymer aerogel, the density of the end product decreased further. Cold regions like the North Pole require high thermal insulation for buildings and fuel tanks to terminate freezing when the temperature goes sub-zero. One of the materials used for insulation of structure is glass fibre which is heavy and adds on load to a building whereas aerogel insulations are ultra-light and can accommodate to requirements of insulation for the long run. While aerogel continues to be one of the finest and most efficient insulating materials to date its economic feasibility is not close to that of classic insulating materials like glass fibre, rock wool, polystyrene etc. The expenditure on aerogel insulation is high and can’t be easily scaled for mass production. The market for aerogels is extensive but the production can’t keep up with the demand because of the long time required for synthesis and its economic instability. Long-term results are expected which would not only cover expenditure but would be a source of revenue if scaled at moderate intervals and inexpensive but suitable for production.

The oil and petroleum industry depends heavily on insulation materials. The oil from deep wells is transported through transmission pipes and the oil being highly viscous is heated so that it can flow easily through pipes but in the course of transportation the oil may lose heat to the surroundings and become thick which can hinder the flow process so to keep the oil hot, pipes are insulated. Insulation covers the outer circumference of the transmission pipeline and then another pipe covers the insulation. It is a pipe in pipe configuration with insulation in between the outer and inner pipe. The most widely used insulation is polyurethane but is not as efficient as Cryogel Z a special class of aerogel it provides three times better insulation than polyurethane. Cryogel Z is developed by Aspen aerogel and is much thinner and lighter than polyurethane which helps in reducing the overall weight of the transmission pipeline. The transmission pipeline with Cryogel Z as insulation material are much easier at installation due to reduced weight more vessels can be employed to lay pipelines on the ocean bed which is economically feasible since when polyurethane is used it makes the pipeline bulky and hence difficult to laying which would require special vessels and would lead to increase in expenditure.

Conclusions:

Aerogels are difficult to produce at a mass scale but production can be scaled further with different methods applied for drying. Drying could be achieved through supercritical drying using an autoclave which is an exorbitant and slow process for mass production. Different approaches such as ambient pressure drying and freeze-drying could be used which are economical for production and scaling up the project. Using an inexpensive and suitable precursor at the initial stage of production can lead to a reduction in expenditure and yet maintain the quality and characteristic features of aerogel. The expenditure on the production line, staff, facility, and energy could be high but the revenue can cover up for the expenditure as the market for aerogel is wide and expanding.

References:

1. Stardust/NExT (weblink)

2. Global aerogel market. (weblink)

3. On the way to commercial production of silica aerogel

4. Taylor-made aerogels through a freeze-drying process: an economic assessment

5. Economic assessment of the production of subcritical dried silica-based aerogels

6. Economic and Energy Life Cycle Assessment of aerogel-based thermal renders

7. CNF-reinforced polymer aerogels: Influence of the synthesis variables and economic evaluation

About the Author:

Amit Prajapati is pursuing his Chemical Engineering at the University School of Chemical Technology(USCT), GGSIP University, Dwarka, Delhi. His main interests are in aerogels, cosmic dust and colloidal chemistry.

📌 Preparation of Silica Aerogels and their Properties

📌 Supercritical Fluids (SCFs) - An Overview

📌 Supercritical Fluids Extraction

📌 Heterogeneous Catalysis - A Walkthrough

📌 Classification of Aerogels