|Title of Invention||
"A PROCESS FOR EXPLOSIVE DETECTION AND IDENTIFICATION"
|Abstract||"A process for explosive detection and identification" This invention relates to a process for explosive detection and identification based on nitramines characterised by single step identification of explosive chemical comprising of three chemical reactants of which one of the reactant is aromatic amine, the second reactant is thymol and the third reactant is Nesscler reagent.|
|Full Text||The present invention relates to a process for explosive detection and identification.
The use of explosives by criminal and terrorist activities is increasing at an alarming rate. The targets chosen are civilian or military installations and populated areas. The attacks in most cases involve explosives based on nitro-esters, riitramines, tri-nitro-toluene etc., or explosive devices known in the art, and such uses lead to large scale destruction and heavy casualties.
This necessitated a method for screening of suspected objects, which in turn may itself be an explosive device or may carry an explosive material, which in turn may be of chemical in nature, such explosives known in the art are like nitroester based, nitramine based, tri-nitro-toluene based etc. or based on combinations thereof, comprising of more than one group of basic explosive chemicals. It is important to detect the type and exact nature of the explosive used in such explosive objects and/or devices, and also the need to detect the type and exact nature of explosive when the explosion has taken place to select the strategy to destroy the detected explosive objects and/or device. Under later circumstances the unreacted explosive materials, which are in turn essentially chemical in nature, as stated herein above and usually present in traces, are highly contaminated with various types of debris such as wood, rnetal pieces and dirt. The detection of explosive materials under such circumstances particularly in exploded areas, is highly tedious and very time consuming exercise, because the sampling has to be made from a large area in large numbers.
The detection of explosive material is generally accomplished by the help of trained dogs. The disadvantage of this method of known art is that the dogs require an elaborate and expensive system of training and yet another drawback of this technique is that the dogs are not always reliable.
Another method of identification of the explosives is the use of explosive detectors. The disadvantage of this method is that there are only a limited number of explosive detectors known at present.
Yet another drawback of this method is that the known explosive detectors are highly expensive and hence limit their wide applications. Still another drawback of such detectors is that these are electronics based and are dependent on batteries, the failure of any such system is obvious and hence, again limits their use.
Yet another method of explosive material's identification from exploded and unexploded site is by the use of explosive detection kits. The known such kits for the explosive detections comprises of basic raw materials, which inturn are chemical in nature. These raw materials are mixed and reacted with the suspected samples collected from exploded or unexploded site. The chemical reactions thus taking place, results in the formation of coloured derivatives of the chemicals present in the collected suspected samples of explosives.
The main disadvantages of presently known such kits for explosive detection is that, these are multireagent kits and the final reagents required to react with the suspected samples, as stated here-in above, are required to be prepared freshly and precisely by accurately weighing the quantities of the starting reagents, precisely called reactants.
Yet another disadvantage of known such kits for explosives detection is that, the chemical reactions involved in the said processes are multistep and hence highly time consuming.
Still another drawback of the kits known in the prior art is that the whole multireagents or precisely called multireactants are allowed to react on the same suspected sample one after one, hence, making the whole process resulting in final explosive detection not only highly time consuming, but also highly tedious and inconvenient and in some cases are misleading.
Still further disadvantage of the kits known in prior art for explosives detection is that, these are suitable for identification of group of the explosive chemicals, and even in some particular cases these can only identify more than one group of explosive chemicals by same multistep chemical reaction. Hence, the presently known such kits for the said purpose are not suitable to identify the individual explosive chemicals. The said disadvantages of known such kits for said purposes makes them limited in their application and wide use in addition to being highly uneconomical.
An object of the present invention is to propose an improved kit for explosion detection and identification hereinabove, and to overcome the disadvantages and drawbacks of the known such kits of the prior art.
The object of the present invention is to propose an improved kit for explosive detection and identifications, which in turn is highly time saving, convenient, and suitable to identify the only one group of the explosive chemicals at one time and as well as individual explosive chemicals in particular cases by formation of the specific colour derivatives of the individual or only one group of explosive chemicals.
Yet another object of the present invention is to propose an improved kit for explosive detection and identification comprising a one step chemical reaction of the ready to use reactants with the suspected samples, herein after referred as starting reactant from suspected site.
Still another object of the present invention is to propose an improved kit for explosive detection and identification wherein the chemical reaction can be carried out on a glass plate or porcelain plate or
even on hands or any body part contaminated with explosive and/or propellant chemicals even in the field conditions in the shortest sequence of chemical spot reactions under preferably all environmental conditions.
According to the present invention a process for explosive detection and identification based on nitramines characterised by single step identification of explosive chemical comprising of three chemical reactants of which one of the reactant is aromatic amine, the second reactant is thymol and the third reactant is Nesscler reagent.
According to main preferred embodiment of the present invention, the presently disclosed improved kit comprises essentially of not more than three reactants, reacting individually with independent batch of starting reactant, which inturn is the sample of explosive chemical drawn from exploded and/or unexploded site, and resulting in formation of specific colour derivative of the suspected explosive chemical, based on the specific chemical reaction between the individual specific reactant of the proposed kit and the starting reactant from the suspected site.
According to another preferred embodiment of the present invention the presently disclosed kit comprises of any two or all the three reactants of which at least one is amine reactant, essentially is aromatic amine, particularly di-phenyl amine, herein after to be named as DPA, and essentially the second reactant is thymol, particularly crystalline thymol, therein after to be named as TH and the third reactant is nessler's reagent, herein after to be named as NR.
Still according to another preferred embodiment of the present invention, the DPA is acidic solution of DPA, preferably 0.1% to 10% acidic solution of DPA made in concentrated sulphuric acid. The TH reactant is crystalline thymole, particularly thymol crystals preferably dissolved in concentrated sulphuric acid and NR is as known in the art.
According to preferred procedure of the present invention the starting reactant is divided into three batches and allowed to react individually with each of the reactant of the proposed kit on any surface, particularly on watch glass or porcelain plate or even on hand or any contaminated body part at normal temperature and pressure conditions.
The advantages of the proposed kit of the present invention and the method of reaction of the said reactants of the said kit are that the whole chemical process for explosive detection and identification completes simultaneously on all the two or three batches of the starting reactant within few minutes preferably upto maximum of five minutes at normal temperature and pressure conditions preferably under all environmental conditions, involving single step chemical reaction in each batch of starting reactant and the reactant of the proposed kit, hence the process being highly time saving, convenient and economical. The further objects, embodiments and advantages of the present invention will be more apparent from the following working examples of the present invention when read in conjunction with the foregoing description.
According to the present invention the suspected reactant, as stated herein above, is directly divided in to two or three batches, essentially not more than three batches, each 2 mg to 10 mgs, preferably 3 mg to 5 mg. Each batch is allowed to react individually and
simultaneously with not more than one reactant of the proposed kit, for preferably two minutes, to yield the specific colour derivative of the suspected explosive chemical. The colour derivative can be used to identify the suspected explosive chemical.
The theoretical samples of explosives/propellants based on nitramines, particularly CTMTN and/or TNPMN and also comprising of nitrates particularly inorganic nitrate, like an and/or particularly organic nitrate, like PETN were prepared and reacted with reactants of the presently disclosed kit according to the preferred procedure of the present invention. EXAMPLE 1
The suspected explosive/propellant comprising of Cyclo Trimethylene Trinitraamine (CTMTN), 2, 4, 6 Tri nitro pheynl Methyl nitriamine (TNPMN) ammonium nitrate and pentaerythritol tetranitrate prepared according to the known procedure was divided into three batchs of 3 mg each, taken on the porcelain plate and are numbered as 1,2 and 3.
3 to 4 drops each of 2% acidic solution of di-phenyl amine, nesseler's reagent and of acidic solution of crystalline thymol are allowed to react individually and simultaneously with sample numbers 1, 2 and 3 respectively.
The yield of blue derivative on reaction of di-phenyl amine solution with suspected reactant in sample number 1 confirms presence of nitramines particularly CTMTN and TNPMN and yield of dirty green derivatives confirms presence of nitrates like organic and/or inorganic nitrates particularly pentaerythritol tetranitrate and/or ammonium nitrate respectively.
The yield of red derivative on reaction of nesseler reagent solution with suspected reactant in sample number 2 confirms presence of nitramine particularly TNPMN and no reaction confirms absence of all, particluarly TNPMN and NC more particularly absence of pentaerythritol letranitrate, when dirty green derivative was formed in reaction of sample and di-phenyl amine solution in batch number 1. The yield of brown derivative on this reaction confirms presence of ammonium nitrate.
The yield of red derivative on reaction of thymol acidic solution with suspected reactant in sample number 3, confirms presence of nitramine, particularly CTMTN and green derivative synthesis confirms presence of nitrates and nitramine, particularly TNPMN. But the presence of TNPMN and ammonium nitrate already confirmed so this reaction confirms presence of pentaerythritol tetranitrate if no derivative was formed on reaction with nersler's reagent.
It is clear from the foregoing example that the suspected explosives/propellants based on nitramines particularly CTMTN and/or TNPMN and also comprising of nitrates, particularly of organic and/or inorganic nitrate could be completely detected by the proposed kit in not more than three, one step and simultaneous chemical reactions being completed in not more than five minutes.
1. A process for explosive detection and identification based on
nitramines characterised by singie step identification of explosive
chemical comprising of three chemical reactants of which one of the
reactant is aromatic amine. the second reactant is thymol and the
third reactant is Nesscler reagent.
2. A process as claimed in claim 1 wherein said aromatic amine, is
diphenyl amine, and second reactant of the said kit is thymol,
preferably thymol crystal, which is dissolved in sulphuric acid,
3. A process as claimed in claims 1 and 2, wherein said diphenyl arnine
is acidic solution of diphenyl amine, preferably 0.1% to 10% acidic
solution of said aromatic amine in sulpheric acid.
4. A process as claimed in claims 1 to 3 wherein said starting reactant
from said suspected unexploded or exploded site is allowed to react
individually, separately and simultaneously with said reactant of said
kit separate batches on said surface at normal temperature and
pressure preferably under all environmental conditions involving
single step reaction, to yield the said colour derivatives as reaction
products of said explosives constituents.
5. A process as claimed in claims 1 to 4 wherein said suspected reactant
is taken directly in 2mg to 10 nig, preferably 3 mg to 5 mg in three
batches, and each said batch is allowed to react with preferably 3 to 4
drops of said reactants individually and simultaneously of said kit.
6. A process for explosive detection and identification substantial as
|Indian Patent Application Number||524/DEL/1996|
|PG Journal Number||9/2010|
|Date of Filing||12-Mar-1996|
|Name of Patentee||THE CHIEF CONTROLLER RESEARCH|
|Applicant Address||B-341,SENA BHAWAN DHQ P.O. NEW DELHI 110011, INDIA|
|PCT International Classification Number||E05G 5/02|
|PCT International Application Number||N/A|
|PCT International Filing date|