materials for commercialization. We foresee and attempted to bring out the clear
picture of the earth abundance crisis in the heterogenous catalytic based environmental remediation. The core concepts explained in this work could be extended to
the other existing technologies.
Keywords Water remediation · Heterogenous catalysis · Materials abundance ·
Environment · Scale up · Commercialization · Toxicity · Material design · Novel
materials · Sustainability · Photocatalyst
7.1 Introduction
7.1.1 Environmental Remediation
Water is often considered as the source of life and the water is essential and flow
through entire earth get pure-impure cycle frequently. The current industrialization
breaks the nature purification cycle due to the huge use of materials and its wastage
(Dapeng and Jiuhui 2009; Dong et al. 2015; Khin et al. 2012; Mills et al. 1993;
Santhosh et al. 2016; Tesh and Scott 2014; Umar and Aziz 2013). The impurities are
contaminating the water and hence consecutively contaminate the land, air, plants
and animals. The remediation aims for water purification till the consumption
standards achieved both for drinking and domestic use. The increase in the world
population and higher standards of people magnify the problem. Because water
purification should be carried out at mass level which require higher quantity of
materials and work force. Hence the toxic impurities are should be removed from the
water to achieve best health for human and the living beings. Additionally, the
technology for the water purification should directly convert toxic molecules to
nontoxic products (Fujishima and Honda 1972; Ku and Hsieh 1992; Matthews
1987; Tanaka et al. 2000). The present work, review environmental remediation of
water using heterogeneous catalyst with focus of earth abundance of materials.
Conventionally, water purified by heterogenous and homogenous catalysis (Chun
et al. 2000; Corma et al. 2010; Descorme et al. 2012; Guillard et al. 2003;
Hajiesmaili et al. 2010; Herrmann et al. 1997; Hu et al. 2011; Jia et al. 2017;
Khanchandani et al. 2013; Malato et al. 2009; Mills and Le Hunte 1997; RamosDelgado et al. 2013; Sun et al. 2006; Thuy et al. 2014). Homogenous catalysis means
catalyst is same phase with water; heterogenous catalysis means catalyst is different
phase than water (mostly solid). Among that, heterogenous catalysis predicted to be
most effective and scientifically proven method for destroying toxic chemicals. The
photocatalyst is often the semiconductor materials (e.g TiO 2 , ZnO, MgO) which
oxidize organic and inorganic contaminates such as halogenated alkanes, alkenes,
and aromatics (e.g Rhodamine B dye) using complex sequence of reaction (Mills
et al. 1993; Mills and Le Hunte 1997; Xia et al. 2016). The mechanism of degradation is simple, semiconducting photocatalyst creates very reactive species in presence of sunlight. The reactive species (OH
radicals) degrade the organic
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J. Nimita Jebaranjitham et al.
picture of the earth abundance crisis in the heterogenous catalytic based environmental remediation. The core concepts explained in this work could be extended to
the other existing technologies.
Keywords Water remediation · Heterogenous catalysis · Materials abundance ·
Environment · Scale up · Commercialization · Toxicity · Material design · Novel
materials · Sustainability · Photocatalyst
7.1 Introduction
7.1.1 Environmental Remediation
Water is often considered as the source of life and the water is essential and flow
through entire earth get pure-impure cycle frequently. The current industrialization
breaks the nature purification cycle due to the huge use of materials and its wastage
(Dapeng and Jiuhui 2009; Dong et al. 2015; Khin et al. 2012; Mills et al. 1993;
Santhosh et al. 2016; Tesh and Scott 2014; Umar and Aziz 2013). The impurities are
contaminating the water and hence consecutively contaminate the land, air, plants
and animals. The remediation aims for water purification till the consumption
standards achieved both for drinking and domestic use. The increase in the world
population and higher standards of people magnify the problem. Because water
purification should be carried out at mass level which require higher quantity of
materials and work force. Hence the toxic impurities are should be removed from the
water to achieve best health for human and the living beings. Additionally, the
technology for the water purification should directly convert toxic molecules to
nontoxic products (Fujishima and Honda 1972; Ku and Hsieh 1992; Matthews
1987; Tanaka et al. 2000). The present work, review environmental remediation of
water using heterogeneous catalyst with focus of earth abundance of materials.
Conventionally, water purified by heterogenous and homogenous catalysis (Chun
et al. 2000; Corma et al. 2010; Descorme et al. 2012; Guillard et al. 2003;
Hajiesmaili et al. 2010; Herrmann et al. 1997; Hu et al. 2011; Jia et al. 2017;
Khanchandani et al. 2013; Malato et al. 2009; Mills and Le Hunte 1997; RamosDelgado et al. 2013; Sun et al. 2006; Thuy et al. 2014). Homogenous catalysis means
catalyst is same phase with water; heterogenous catalysis means catalyst is different
phase than water (mostly solid). Among that, heterogenous catalysis predicted to be
most effective and scientifically proven method for destroying toxic chemicals. The
photocatalyst is often the semiconductor materials (e.g TiO 2 , ZnO, MgO) which
oxidize organic and inorganic contaminates such as halogenated alkanes, alkenes,
and aromatics (e.g Rhodamine B dye) using complex sequence of reaction (Mills
et al. 1993; Mills and Le Hunte 1997; Xia et al. 2016). The mechanism of degradation is simple, semiconducting photocatalyst creates very reactive species in presence of sunlight. The reactive species (OH
radicals) degrade the organic
196
J. Nimita Jebaranjitham et al.